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Polylactic acid (PLA) has garnered significant interest as a bio-based polymer due to its favorable thermal and processing characteristics, as well as its notable economic and environmental benefits. However, the drawbacks such as flammability and poor toughness of PLA severely constrained its applications in more fields. Here, based on the outstanding flame-retardant properties of core-shell flame retardant (CSFR) and the toughening potential of natural rubber (NR), we synthesized inorganic-organic hybrid of CSFR-NR using an aqueous synthesis to synchronous optimization of the comprehensive performance of PLA. The as-prepared CSFR-NR with "hard core and soft shell" possess the ability to promote char formation and facilitate uniform dispersion in the PLA matrix. Consequently, the PLA/CSFR-NR showed an excellent flame retardancy with the limiting oxygen index (LOI) value of 31.5 % and UL-94 V-0 rating and synergistic toughening effect with absolutely improvement in elongation at break and notched izod impact strength, achieving a balance between the fire safety and mechanical performance. Moreover, the degradation rate of PLA has also been substantially promoted by CSFR-NR in simulated seawater. Hence, this study offers a straightforward, efficient, and environmentally friendly strategy for creating high-performance flame retardant and toughened bioplastics. • A inorganic-organic hybrid of CSFR-NR is synthesized to optimization of the flame retarding and toughening effect for PLA. • The PLA/CSFR-NR composites show excellent flame retardancy with the LOI value of 31.5 % and UL-94 V-0 rating. • The PLA/CSFR-NR exhibits toughening effect with improvement in elongation at break and notched izod impact strength. • The presence of CSFR-NR in PLA accelerated the hydrolytic degradation of PLA in simulated seawater. [ABSTRACT FROM AUTHOR]

In this study, a novel Z-scheme Bi 19 S 27 Br 3 /CoAl-LDH heterojunction was prepared. An interface charge transfer channel was established between Bi 19 S 27 Br 3 and CoAl-LDH, accelerating the transition efficiency of interface electrons from CoAl-LDH to Bi 19 S 27 Br 3. Thereby ensuring more excited electrons to participate in CO 2 photoreduction reactions. The reduction products were tested under artificial light conditions, and triethanolamine was selected as a sacrificial agent. After 5 h of illumination, the CO yield of Bi 19 S 27 Br 3 /CoAl-LDH Z-scheme heterojunction was 86.41 μmol·g−1 is 4 times and 7 times higher than Bi 19 S 27 Br 3 and CoAl-LDH, respectively. The yield of CH 4 in Bi 19 S 27 Br 3 /CoAl-LDH is 3.97 μmol·g−1 is 4 times higher than CoAl-LDH. Also Bi 19 S 27 Br 3 itself does not produce CH 4. The results indicate that the Z-scheme heterojunction effectively enhances the photoreduction ability of CO 2 , providing a new approach for accurately controlling the direction of photo generated charge separation to prepare high-performance photocatalysts. [Display omitted] • Z-scheme heterojunction improves the efficiency of charge utilization and retains a large number of reducing electrons. • Bi 19 S 27 Br 3 /CoAl-LDH has good photocatalytic reduction performance of CO 2. • Bi 19 S 27 Br 3 acts as an electronic collector. • composite photocatalyst has excellent chemical stability. • The electron migration pathways were determined through electrochemistry, ESR, UPS and DFT, demonstrating the high photocatalytic reduction performance of the composite material. [ABSTRACT FROM AUTHOR]

The Z-scheme α-Fe 2 O 3 /BiVO 4 photocatalyst was synthesized by a simple hydrothermal method. The photocatalyst is composed of α-Fe 2 O 3 nanocubes with a regular cubic structure and the BiVO 4 particles distributed on the surface of the α-Fe 2 O 3 nanocubes. The photocatalytic performance of Z-scheme α-Fe 2 O 3 /BiVO 4 photocatalyst was investigated in terms of its capacity for photodegradation of tetracycline hydrochloride. Improved photocatalytic activity was observed for Z-scheme α-Fe 2 O 3 /BiVO 4 photocatalyst compared with single BiVO 4 and α-Fe 2 O 3 nanocubes under visible light irradiation. Studies of its morphology, physicochemical properties and photoelectrochemical behaviors demonstrated that BiVO 4 loading on the surface of α-Fe 2 O 3 nanocubes forms a Z-scheme heterojunction, which increases the specific surface area and significantly promotes the separation of photoinduced carriers. The main active species were determined to be OH and h+ by ESR technique and trapping experiments. We propose a possible photocatalytic mechanism of Z-scheme α-Fe 2 O 3 /BiVO 4 photocatalyst system. This study may also provide a novel and eco-friendly demonstration of a useful strategy for the design and preparation of special structure photocatalytic materials. The Z-scheme BiVO 4 /α-Fe 2 O 3 photocatalyst was synthesized by a simple hydrothermal method. The photocatalyst is composed of α-Fe 2 O 3 nanocubes with a regular cubic structure and the BiVO 4 particles distributed on the surface of the α-Fe 2 O 3 nanocubes. The photocatalytic performance of Z-scheme BiVO 4 /α-Fe 2 O 3 photocatalyst was investigated in terms of its capacity for photodegradation of tetracycline hydrochloride. Improved photocatalytic activity was observed for Z-scheme BiVO 4 /α-Fe 2 O 3 photocatalyst compared with pure BiVO 4 and α-Fe 2 O 3 nanocubes under visible light irradiation. Studies of its morphology, physicochemical properties and photoelectrochemical behaviors demonstrated that BiVO 4 loading on the surface of α-Fe 2 O 3 nanocubes forms a Z-scheme heterojunction, which increases the specific surface area and significantly promotes the separation of photoinduced carriers. The main active species were determined to be OH and h+ by ESR technique and trapping experiments. We propose a possible photocatalytic mechanism of Z-scheme BiVO 4 /α-Fe 2 O 3 photocatalyst system. This study may also provide a novel and eco-friendly demonstration of a useful strategy for the design and preparation of special structure photocatalytic materials. [ABSTRACT FROM AUTHOR]

It is still a challenging work to realize the universality of photocatalytic materials for unselectively removing environmental pollutants in water. Here, a ternary magnetism CoFe2O4/g-C3N4/HNTs heterojunction photocatalyst is firstly prepared, and the morphology, crystalline property, surface area, and magnetic recycling capability of the photocatalyst were investigated. The CoFe2O4/g-C3N4/HNTs shows a superior degradation efficiency for degrading 2-mercaptobenzothiazole (MBT) than that of pure g-C3N4. The high degradation performance that derives from the hollow structure of halloysite nanotubes (HNTs) can inhibit stacking of g-C3N4, which results in a larger specific surface area and more abundant reaction sites. Meanwhile, the heterojunction structure between g-C3N4 and CoFe2O4 improved the separation efficiency of charge carriers. In addition, the intermediate products, degradation pathway, and reaction mechanism of representative MBT pollutant over the CoFe2O4/g-C3N4/HNTs photocatalyst are revealed in depth. This work makes an important development. [ABSTRACT FROM AUTHOR]

A new Z-scheme MoS2/Bi2O3 heterojunction photocatalyst was successfully prepared using a facile and practical hydrothermal method. The Z-scheme MoS2/Bi2O3 heterojunction exhibits a superior degradation efficiency compared to pure MoS2 and Bi2O3 for removing industrial and domestic pollutants under visible light, such as 2-mercaptobenzothiazole, tetracycline and rhodamine B. The enhancement in the photocatalytic performance mainly stems from the interfacial interaction between the MoS2 nanosheets and Bi2O3 rods, which can increase the specific surface area and accelerate the separation of the photo-induced electron–hole pairs. To explain this interfacial interaction between MoS2 and Bi2O3 in the Z-scheme MoS2/Bi2O3 heterojunction, several characterization techniques were applied. In addition, the photocatalytic mechanism for degrading pollutants was demonstrated using trapping experiments and electron spin resonance. This work could provide a promising approach for the formation of other Z-scheme transition metal compound heterojunctions with outstanding photocatalytic activity. [ABSTRACT FROM AUTHOR]

A defect-free ZIF-8 membrane on a porous ceramic tube was well prepared by the self-conversion of ZnO nanorods in a zinc-free 2-methylimidazole (Hmim) water-solvent solution. In the synthesis, the ZnO nanorods grown on the substrate provide the zinc source and act as the nucleation and growth sites for the ZIF-8 membrane, thus contributing to the formation of a high-quality ZIF-8 membrane with the ideal selectivity of over 40 for H 2 /CH 4. Most importantly, it is found that after the one-time membrane synthesis, the used solution could be still recycled for the self-conversion of ZnO nanorods to ZIF-8 membranes. The results show that each self-converted synthesis merely consumed around 0.005 M ligand for achieving a continuous ZIF-8 membrane, and thus the solution with the ligand concentration of 0.5 M could be repeatedly used for at least 50 times for preparing compact ZIF-8 membranes without any treatment. Moreover, when the synthesis solution of around 0.2 M produced after the recycling for 60 times is recovered to the one of 0.5 M by adding fresh Hmim ligand, the obtained solution of 0.5 M could again act as the membrane synthesis one for the self-conversion of ZnO nanorods into the compact ZIF-8 membrane. Moreover, it could be also recycled for another 50 times for the synthesis of ZIF-8 membrane as the first-stage recycling, thus realizing a sustainable synthesis without any wastewater discharge. The present strategy is an environmental friendly and low-cost method for the scalable preparation of a ZIF-8 tubular membrane and of potential in practical applications. Image 1 • A ZnO nanorods self-converted strategy was employed to prepare a compact ZIF-8 membrane in a Zn-free water-solvent solution. • The synthesis solution could be recycled for over 50 times for growing dense ZIF-8 membranes without any treatment. • The strategy is a recyclable environmentally friendly synthesis process without any wastewater discharge. [ABSTRACT FROM AUTHOR]

The cobalt doped cadmium selenide/biomass carbon spheres (Co-CdSe/BCS) photocatalyst is easily prepared using a transitory hydrothermal reaction lasting 40 min. The Co-CdSe/BCS photocatalyst is constructed using the in situ growth of Co-CdSe nanodots on the surfaces of the BCS. Doped Co2+ generates an electron trap, which can capture the photoinduced electrons, resulting in the efficient separation of the photoinduced electron–hole pairs. Furthermore, the introduction of carbon spheres enhances the optical absorption property and the ability for electron transport. Results of electrochemical characterization and photoluminescence spectra demonstrate that the Co-CdSe/BCS is able to efficiently separate electron–hole pairs and inhibit their recombination. The as-synthesized samples display high efficiency for the photodegradation of methylene blue dye under visible light. This study offers a new strategy to promote photocatalytic performance of the CdSe photocatalyst. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The Fe(III) species act as electrons trapping centers to promote charge separation. • The self-induced Fenton reaction process of Fe(III) enhances the yield of OH. • The Fe(III)-BVO exhibits universal photoactivity for various organic pollutants. Abstract A novel self-induced Fenton-like photocatalyst (Fe(III) grafted BiVO 4) has been successfully synthesized via a simple wet-impregnation method, and it presents a universal enhancement for removing antibiotics and phenolic pollutants under visible light irradiation. Results reveal that the grafting of Fe(III) enhances the specific surface area of sample and possess more reaction sites. Meanwhile, the Fe(III) species serve as trapping centers for photogenerated electrons to improve the separation ability of charges, and the self-induced surface Fenton reaction of the self-redox cycles of iron ions significantly promote the generation of hydroxyl radicals. Additionally, the possible reaction mechanism and intermediate products are clearly revealed by radical trapping experiment, ESR, detection experiment of hydroxyl radicals and mass spectrometry. This strategy provides a promising insight to construct high-performance photocatalyst for solving environmental pollution problem. [ABSTRACT FROM AUTHOR]

A novel ternary Cu2O/BiVO4/RGO photocatalyst is successfully constructed by hydrothermal and evaporation-induced method, and it exhibits superior photocatalytic performance for degradation tetracycline (TC). Meanwhile, the visible light absorption range of composite photocatalyst is effectively broadened by the formation of heterojunction with narrow band gap semiconductor Cu2O. And the separation efficiency of the photogenerated electron–hole pairs is significantly enhanced by the synergistic effect of Cu2O and RGO. More importantly, the adsorption of TC by ternary Cu2O/BiVO4/RGO possesses high adsorption capacity, which is 23.73 times higher than that of pure BiVO4. Additionally, the possible reaction mechanism is clearly revealed by radical trapping experiment, electron spin-resonance (ESR) spectroscopy. This work provides a new insight to design a photocatalyst with excellent adsorption to remove organic contaminants in water. In this work, the Cu2O/BiVO4/RGO photocatalyst was successfully constructed by hydrothermal and evaporation-induced method, and their high photocatalytic activity was reported. The separation efficiency of the photogenerated electron–hole pairs is significantly enhanced by the synergistic effect of the Cu2O and RGO. Thus, the photocatalyst can exhibit superior photocatalytic performance for the degradation tetracycline. [ABSTRACT FROM AUTHOR]

A novel multidimensional heterojunction, the 1D trigonal Se nanorods (t-Se NRs) dissociated from CdSe QDs germinating on the 2D BiOCl ultrathin nanosheets, was successfully synthesized via a facile hybridization method. Such unique nanocomposite served as an efficient visible-light-driven photocatalyst for the photodegradation of the tetracycline hydrochloride (TC-HCl) solution. The obviously enhanced photocatalytic performance compared with pure BiOCl was mainly attributed to the introduction of Se NRs, which greatly enhanced the optical absorption in visible-light region and suppressed the recombination rate of electron-hole pairs by steering the charges migrating in a special manner. Specially, t-Se NRs in BiOCl system played an integral and important role as holes transfer channels, impelling more photogenerated electrons of BiOCl to participate in the photocatalytic process. Reactive species trapping experiments indicated the main reactive species were O 2 – radicals, which were generated by the collisions of excited electrons and molecular oxygen. Meanwhile, the radically increased ESR peak of O 2 – radicals for the heterogenous materials demonstrated successful release of abundant high-energy electrons. This work could be extended to the design of other robust 1D/2D heterojunction photocatalysts in application to the environmental demands. [ABSTRACT FROM AUTHOR]

In this paper, the biomass carbon quantum dots (CQDs) modified flower-like BiOI (CQDs/BiOI) composite photocatalyst was synthesized by a facile solvothermal method. Compared with the pristine BiOI, the biomass CQDs/BiOI exhibited outstanding photocatalytic activity for degradation of the typical methylene blue (MB) under visible light irradiation since the biomass CQDs could act as electron acceptors to effectively facilitate the separation efficiency of photon-generated carriers and prolong their lifetime. Furthermore, the mechanism detection experiment showed that the and H were major activity species, and the photocatalytic electron transfer mechanism was further investigated. This work provided a new insight into biomass CQDs effects and took an important step toward the development of improving Bi-based semiconductor photocatalyst activity. In this work, biomass carbon quantum dots/bismuth oxyiodide microflower was prepared by a facile solvothermal method, and their high photocatalytic activity was reported. The biomass carbon quantum dots worked as electron acceptors, which can improve the separation efficiency of the photo-generated electrons and holes to promote high photocatalytic activity. [ABSTRACT FROM AUTHOR]

Visible-light-driven photocatalysis as a green technology has attracted a lot of attention due to its potential applications in environmental remediation. Vesicle CdSe nano-semiconductor photocatalyst are successfully prepared by a gas template method and characterized by a variety of methods. The vesicle CdSe nano-semiconductors display enhanced photocatalytic performance for the degradation of tetracycline hydrochloride, the photodegradation rate of 78.824% was achieved by vesicle CdSe, which exhibited an increase of 31.779% compared to granular CdSe. Such an exceptional photocatalytic capability can be attributed to the unique structure of the vesicle CdSe nano-semiconductor with enhanced light absorption ability and excellent carrier transport capability. Meanwhile, the large surface area of the vesicle CdSe nano-semiconductor can increase the contact probability between catalyst and target and provide more surface-active centers. The photocatalytic mechanisms are analyzed by active species quenching. It indicates that h + and O 2 − are the main active species which play a major role in catalyzing environmental toxic pollutants. Simultaneously, the vesicle CdSe nano-semiconductor had high efficiency and stability. [ABSTRACT FROM AUTHOR]

Heterojunction with nano-level interfacial contact has an advantage in improving the transfer capacity of photongenerated carriers. In consequence, a heterojunction composite with nano-level interfacial contact was developed by establishing CdSe/Al 2 TiO 5 heterojunction composites. The heterojunction composite was established by combining Al 2 TiO 5 and CdSe nanocrystals. They provided superior nano-level interfacial contact. The photocatalytic activity of heterojunction composites were illustrated to be significantly improved compared to that of pure Al 2 TiO 5 and CdSe nanocrystals. Moreover, the photocurrent intensity of heterojunction composites displays a several times enhancement, implying the promotion of photocatalytic activity was owned to the nano-level interfacial contact with ideal photogenerated electron-hole pairs transfer behavior. [ABSTRACT FROM AUTHOR]

In this paper, a novel heterostructure of 0D/3D-CdSe/BiTiO pyramidal photocatalyst was synthesized and characterized. It exhibited significantly photocatalytic efficiency in photocatalytic degradation of the tetracycline than pure BiTiO2 and CdSe and showed high stability. The enhanced photocatalytic activity might be attributed to the formation of heterostructure between CdSe QDs and 3D BiTiO, in which CdSe QDs served as electron trapper to improve the separation of photodegradation electron-hole pairs, and provided a number of active adsorption sites for the photogenerated of pollutants. The photocatalytic mechanism of 0D/3D-CdSe/BiTiO pyramidal heterostructure was also proposed. In this work, 0D/3D-CdSe/Bi12TiO20 pyramidal heterostructure photocatalyst was prepared by hydrothermal method, and reported high photocatalytic activity. The heterojunction was formed at the composite photocatalyst, can easily allow the excited electron on the Bi12TiO20 surface to CdSe. Thus, the photo-generated electrons and holes can be separated effectively to promote high photocatalytic activity. [ABSTRACT FROM AUTHOR]

The effect of metal ion doping on the electronic structure and optical properties of CdSe quantum dots has been investigated by various characterization techniques and experiments. Various cation codoped CdSe quantum dot photocatalysts were synthesized via a hydrothermal method. The prepared quantum dots were examined using X-ray diffraction, fluorescence spectroscopy, X-ray photoelectron spectroscopy, high resolution transmission electron microscopy, and UV–vis diffuse reflectance spectroscopy. The activities of the photocatalysts were evaluated with respect to the photodegradation of tetracycline hydrochloride solutions under simulated sunlight irradiation. 3%Co–4%K/CdSe quantum dots showed a higher photocatalytic activity than others within 30 min of visible light irradiation. Furthermore, there was hardly any decrease in the catalytic efficiency after the fourth experimental cycle. Identification data illustrate that Co and K codoping may cause improvement in the photocatalytic performance of CdSe quantum dots, which is crucial for tetracycline hydrochloride degradation under simulated sunlight irradiation. Therefore, this study demonstrates a promising strategy for the design of highly efficient photocatalysts for the remediation of aqueous pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A continuous and dense MAF-5 membrane was fabricated for the first time for hydrogen separation. • The activation of the ZnO nanorods and the material ratio of synthetic solution are crucial for MAF-15 membrane fabrication. • The MAF-5 membranes exhibit excellent H 2 separation performance and high stability and reproducibility. For the first time, a homologous metal oxides induced approach was used to fabricate MAF-5 membrane for small molecule separation systems. A continuous and dense MAF-5 membrane was well formed on a porous ceramic substrate by the localized conversion of a thinlayer of ZnO nanorods. The ZnO nanorods layer acting as an intermediate plays a multifunctional role in the formation of the high-quality MAF-5 membrane: (1) modifying the porous substrate to make it more smooth and even; (2) inducing the nucleation and growth of MAF-5 membrane; (3) connecting the MAF-5 membrane and substrate tightly to avoid the membrane peeling off. The as-prepared membrane was characterized by various techniques and proved that the membrane is continuous and high-quality. The excellent gas permeation performance for the MAF-5 membrane was achieved for single gases. The ideal selectivities were as high as 80.2, 87.1 and 105.7 for H 2 /CO 2 , H 2 /N 2 and H 2 /CH 4 , respectively, which are far higher than their corresponding Knudsen diffusion values. It is therefore believed that the MAF-5 membrane is of potential application in the field of some small-molecular gas separation through a molecular sieving effect. [ABSTRACT FROM AUTHOR]

Inthis paper, CdSe quantum dots (QDs) photocatalysts were successfullysynthesized by a hydrothermal method. The factors affecting synthesizedCdSe QDs were investigated under different experimental conditions.CdSe QDs were characterized by X-ray diffraction (XRD), Fourier transforminfrared (FT-IR) spectroscopy, transmission electron microscopy (TEM),ultraviolet–visible diffuse reflectance spectrophotometry (UV–visDRS), photoluminescence (PL) spectroscopy, and X-ray photoelectronspectroscopy (XPS). The photocatalytic activities of CdSe QDs wereevaluated on the decomposition of cefalexin under UV irradiation.The results showed that the degradation ratio of Cefalexin could reach70.34%. Based on the results, the possible mechanism of the photocatalyticreaction on cefalexin with CdSe QDs was discussed. [ABSTRACT FROM AUTHOR]

Preparation of defect-free and stable metal-organic framework tubular membrane for liquid separation is still a great challenge. In this work, a high-quality bimetallic Zn/Co-ZIF tubular membrane was fabricated via a novel strategy on a porous ceramic tube for the highly efficient separation of methanol (MeOH)/methyltert-butylether (MTBE) mixture by pervaporation. The strategy includes first the introduction of a thinlayer of Zn/Co hydroxy double salts (HDSs) on the tube surface and then the facile conversion of the HDS layer to a dense and stable bimetallic Zn/Co-ZIF membrane. The achieved membrane can preferentially separate MeOH from the 15 wt% MeOH/MTBE mixture and display an ultrahigh separation performance with flux of 1.96 kg m−2 h−1 and separation factor of 6985. It can also demonstrate an excellent long-term operating stability benefited from the HDS layer acting as an inorganic linker. Therefore, the bimetallic Zn/Co-ZIF membrane has great industrial application potential for the separation of MeOH/MTBE mixture. [Display omitted] • Bimetallic Zn/Co-ZIF membrane was fabricated by the self-converted strategy of Zn/Co-HDS. • The membrane was prepared in a ligand water-solvent solution, showing an environmentally-friendly synthesis. • The membrane exhibited excellent PV separation performance for MeOH/MTBE mixture. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel CD-BVO/rGH photocatalyst was constructed by coupling Carbon dot-coupled BiVO 4 with rGH. • CD-BVO/rGH display enhanced photocatalytic activity for TCH degradation and CO 2 reduction. • The synergetic effects of CD-BVO and rGH can enhanced the separation of carriers. • Possible photocatalytic reaction mechanism of TCH degradation and CO 2 reduction was presented. In this study, we fabricated a novel hybrid photocatalyst (CD-BVO/rGH) by coupling carbon dot (CD)-decorated BiVO 4 (BVO) with a reduced graphene hydrogel (rGH). The CD-BVO/rGH photocatalyst significantly enhanced the photocatalytic efficiency for tetracycline hydrochloride (TCH) degradation compared with pure BVO and BVO/rGH under simulated solar irradiation. CD-BVO/rGH also showed a substantial performance in the photocatalytic reduction of CO 2. The enhanced photocatalytic activity of CD-BVO/rGH is attributed to synergistic effects, such as better light energy utilization via the upconversion effects of the CDs and the enhanced migration and separation of photoexcited carriers by the three-dimensional (3D) network structure of the rGH. The systematic analysis of the band structure, electron spin resonance, and free radical trapping revealed that h+ and O 2 – mediate the final photocatalytic degradation of pollutants. Our results provide insight into the design and construction of highly efficient hybrid photocatalysts combined with functional carbon nanostructures to enhance the photocatalytic activity for the photodegradation of environmental pollutants and CO 2 reduction. [ABSTRACT FROM AUTHOR]

The construction of efficient and low-cost photocatalytic systems is a major challenge in the field of photocatalysis. An efficient heterojunction photocatalyst designed for water splitting is also an interesting prospect in energy conversion. In this study, a novel Mn 0.43 Cd 0.57 S/ZnCo 2 O 4 p-n heterojunction photocatalyst was prepared via a simple solvothermal method. Mn 0.43 Cd 0.57 S was loaded on the surface the of noble metal-free transition metal oxide ZnCo 2 O 4 to prevent the agglomeration of particles, resulting in efficiently improving the photocatalytic performance of the material. Due to the Fermi level balance, the band bending of the two materials constructs a p-n heterojunction, which stimulates the transfer of photogenerated electrons from the CB of Mn 0.43 Cd 0.57 S to the CB of ZnCo 2 O 4. The uniformly dispersed p-n heterojunction structure effectively suppresses the recombination of photoinduced charges and preserves stronger redox charges. As a result, the established Mn 0.43 Cd 0.57 S/ZnCo 2 O 4 heterojunction showed the best photocatalytic hydrogen production concentration (92.1 mmol g−1 h−1), which was 4.7 times that of the original Mn 0.43 Cd 0.57 S (19.4 mmol g−1 h−1) and 54.2 times that of ZnCo 2 O 4 (1.7 mmol g−1 h−1). This strategy will provide new insights into the development of new photocatalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Controllable synthesis of metal organic frameworks (MOFs) crystals with definite morphology and topology plays an important role in determining the property and application of MOFs materials, especially bimetallic MOFs which have exhibited an improved performance in many fields due to the incorporation of the second metal ion. Herein, we for the first time report a simple and convenient method of the self-conversion of hydroxy double salts (HDSs) for synthesizing bimetallic MOFs with controllable morphology and topology by merely adjusting the synthesis conditions. As the sample, we employed Zn/Co-HDS as metal source and 2-methylimidazole (HMeIm) and 2-ethylimidazole (HEtIm) as organic ligands, respectively, to investigate the effects of the synthesis conditions on the morphology and topology of Zn/Co bimetallic MOF. The arbitrary transformation with two topologies (SOD and dia) and four morphologies (2D nanosheets, rhombic dodecahedron, truncated rhombic dodecahedron and truncated cubes) of the bimetallic Zn/Co(MeIm) 2 was achieved by adjusting synthesis solvent, reaction time and ligand concentration. Analogously, three other topologies (ANA, RHO and QTZ) were also discovered in the bimetallic Zn/Co(EtIm) 2 by simply adjusting the synthesis conditions. It is thought that the different synthesis conditions in the preparation of bimetallic MOFs are closely related to the supersaturation of crystal growth unit, thus affecting the morphology and topology of the products. Therefore, this novel synthesis strategy is highly efficient for preparing bimetallic MOFs with controllable morphology and topology. [Display omitted] • Bimetallic Zn/Co(MeIm) 2 and Zn/Co(EtIm) 2 were fabricated by the self-conversion of Zn/Co-HDS. • The morphology and topology of the bimetallic MOFs could be regulated by adjusting the synthesis conditions. • The bimetallic MOFs with different morphologies and topologies have potential applications in many fields. [ABSTRACT FROM AUTHOR]

In this study, we report the construction of a novel composite photocatalyst (BiVO 4 /rGH) composed of quantum dots (QDs) self-decorated BiVO 4 -nanoparticels (NPs) and reduced graphene hydrogel (rGH). The composite structures were prepared using an in-situ growth method. The BiVO 4 /rGH composite photocatalysts exhibited excellent photocatalytic efficiency for the degradation of tetracycline hydrochloride (TC HCl). The promoted photocatalytic activity of the BiVO 4 /rGH is attributed to the synergetic effects of the unique structure involving QDs self-decorated BiVO 4 NPs and a 3D network structure of rGH, which resulted in higher number of photogenerated charge carriers, surplus active sites, and enhanced charge separation. In addition, trapping measurements showed that ·O 2 − and h+, as the main active species, play a crucial role in the degradation of TC HCl over the composite photocatalyst. This study facilitates the design and construction of high efficiency hybrid photocatalysts with multifunctional materials for the removal of water pollutants. [Display omitted] • A novel QDs-BiVO 4 /rGH photocatalyst was constructed by coupling QDs self-decorated BiVO 4 with rGH. • QDs-BiVO 4 /rGH display enhanced photocatalytic activity for TC HCl degradation. • The synergetic effects of QDs-BiVO 4 and rGH can enhanced the separation of carriers. • A possible photocatalytic reaction mechanism of TC HCl degradation was presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-GNDs/Ag/BiVO 4 is constructed by co-deposition N-GNDs and Ag-NPs on the BiVO 4 surface. • N-GNDs/Ag/BiVO 4 display enhanced photocatalytic activity than that of BiVO 4. • The synergistic effects of Ag-NPs and N-GNDs enable a full-spectrum response to light. • Schottky energy barrier and electron trap restrain the recombination of carries. • Possible photocatalytic mechanism and intermediates for TC•HCl degradation is proposed. The efficient removal of antibiotics in water is essential to protect aquatic environment as antibiotics are some of the most hazardous pollutants in water. Herein, we report the synthesis of a novel N-GNDs/Ag/BiVO 4 ternary photocatalyst consisting of BiVO 4 coupled with Ag nanoparticles (Ag-NPs) and nitrogen-doped graphene nanodots (N-GNDs) to degrade and mineralize tetracycline hydrochloride (TC•HCl) in water. The ternary photocatalyst shows higher photocatalytic degradation of TC•HCl under full spectrum light than pure BiVO 4. Based on the morphology, crystalline structure, physicochemical properties, and photoelectrochemical behavior of the ternary photocatalyst, the enhanced photocatalytic performance is attributed to the upconversion effect of N-GNDs and the localized surface plasmon resonance (LSPR) effect of Ag-NPs. Thus, the synergetic effects expand the absorption range of light and significantly promotes the separation of photoexcited carriers. Further, a possible photocatalytic reaction mechanism of TC•HCl degradation over N-GNDs/Ag/BiVO 4 is discussed via through investigation of the charge carrier migration, active species, and intermediates in the degradation processes. [ABSTRACT FROM AUTHOR]

• The Ce-C@g-C 3 N 4 was firstly synthesized by plant growing guide and calcination method. • The alternanthera philoxeroides griseb-based biochar can significantly against the g-C 3 N 4 reunion and stacking. • The introduced biochar increased g-C 3 N 4 active sites and enhanced the electron-holes separation efficiency. • This work provides a new avenue for high performance photocatalysts via plant growing guide. In the present study, we constructed the Ce-doped biomass carbon-based mesoporous g-C 3 N 4 photocatalyst via alternanthera philoxeroides griseb growing guide using calcination method. The Ce-C@g-C 3 N 4 exhibited more superior photocatalytic performance for 2-mercaptobenzothiazole (96 %) degrading than that of pure g-C 3 N 4 (39 %) and C@g-C 3 N 4 (60 %). As a consequence, the improved degradation efficiency of Ce-C@g-C 3 N 4 attributed to the biomass carbon can significantly enhance the mass transport channels of electron-hole pairs. Meanwhile, the doped Ce4+ ions acting as the redox center can sufficiently utilize the photogenerated carriers for generating more active radicals. Also, the possible photocatalytic reaction mechanisms including transfer behaviors of charge carriers, generation of reactive species, intermediate degradation products are also discussed in detail. This work may provide a promising approach for synthesizing g-C 3 N 4 -based photocatalyst by the plant growing guide and application in wastewater treatment. [ABSTRACT FROM AUTHOR]

• A layer of highly oriented Zn 2 (bIm) 4 nanosheet membrane was successfully grown on stainless steel meshes (SSMs). • The like-fish-scale structure of the nanosheet membrane increased the surface roughness and hydrophobicity of the SSMs. • The membrane exhibited excellent separation performance for both free oil/water mixtures and water-in-oil emulsion. Due to frequent oil spill accidents, the efficient separation of oil/water mixtures is attracting one's attention. In this work, we adopt a direct growth strategy for preparing continuous and highly oriented Zn 2 (bIm) 4 (bIm = benzimidazole) ZIF nanosheet membranes on stainless steel meshes (SSMs) as substrate by the self-conversion of vertically arranged ZnO nanorods grown on the SSMs. This kind of perpendicularly oriented nanosheet membrane has superhigh hydrophobicity and special microstructure and thus is very promising for fabricating membrane separators and application in oil removal. On the SSMs with different meshes (500 mesh and 2000 mesh), the corresponding ZIF nanosheet membranes were successfully fabricated by the oriented growth of nanosheets to form different separators called as ZNM-SSM-500 and ZNM-SSM-2000, respectively. They were applied in the separation of different oil/water mixtures by using dichloromethane, petroleum ether, n-hexane, toluene, nitrobenzene and cyclohexane as model oils, and could demonstrate excellent separation performance. The ZNM-SSM-500 separator shows a separation efficiency of 99.8% with high flux of over 100,000 L m−2 h−1 for free oil/water mixtures containing 50 wt% water, while the ZNM-SSM-2000 separator exhibits a water rejection of as high as 99.95% for water-in-oil emulsions containing 2 wt% water. Moreover, the resulting nanosheet membrane could also demonstrate excellent thermal stability and recyclability. Therefore, the oriented nanosheet membrane is of great application potential in practical oil/water separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • CatBoost was used to predict the stability of MOFs in water. • 5-fold cross-validation and hyperparameter tuning were employed. • SHAP addition interpretation explains the feature importance of CatBoost. • Ionization potential, number of cyclic divalent nodes, six-member rings were the key factors. Metal-organic frameworks (MOFs) were considered suitable candidates for a range of industrial applications, including adsorption, separation, sensing and catalysis, due to their advantages of diverse structures and adjustable functions. One of the criteria for determining the commercial viability of MOFs is their stability in water vapor. Here, we established a novel Categorical Boosting (CatBoost) machine learning approach to model more than 200 datasets of empirical measurements of MOF water stability, and used a comprehensive set of chemical descriptors to represent MOF composition including metal ions, organic ligands, and metal–ligand molar ratios. CatBoost algorithm was significantly superior to other gradient algorithms in accuracy, precision and F1-Score. Also, the CatBoost output was interpreted using the Shapley additive interpretation (SHAP) method. Besides providing guidelines for future experimental screening of stable candidates for MOFs, the interpretable Catboost model can also be used for MOFs screening of other design criteria. [ABSTRACT FROM AUTHOR]

• The direct Z-Scheme heterojunction improve the utilization efficiency of charge and retain great redox capacity. • ZCS/MOF-199 have excellent activity for photocatalytic hydrogen evolution. • The framework provided by MOF-199 allowed ZCS to expose more active sites. • The composite photocatalysts owned excellent chemical stability. This work reports a simple ultrasonic impregnation method, using MOF-199 as the carrier platform to construct direct Z-Scheme ZnCo 2 S 4 /MOF-199 (ZCS/M) for stable and efficient photocatalytic hydrogen (H 2) evolution. Under simulated sunlight, ZCS/M shows high photocatalytic activity, with H 2 evolution amount of 11.6 mmol·g−1·h−1, which is 48.4 and 83.3 times of MOF-199 and ZCS respectively, and the apparent quantum efficiency (AQY) reaches 4.92 % at 420 nm. The successful construction of direct Z-Scheme heterojunction greatly improves the separation of electron-hole pairs to promote photocatalytic H 2 evolution. In addition, ZCS is evenly anchored on the surface of MOF-199, which effectively solves the problem that ZCS is easy to agglomerate, and exposes more active sites. In-situ XPS, VB, band gap, work function and Fermi level is used to analyze the Fermi level alignment, interfacial built-in electric field and band bending, and photocatalysis mechanism and path of electron migration is speculated. This work provides a new strategy for the design and construction of direct Z-Scheme heterojunction with transition metal sulfide on the platform of MOF to enhance photocatalytic H 2 evolution during water splitting. [ABSTRACT FROM AUTHOR]

ZnO/g-C3N4 was prepared by carrying out a simple one-step calcination process. The ZnO/g-C3N4 composite was characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS), electrochemical impedance spectroscopy (EIS), transient photocurrent responses and photo-luminescence (PL) spectroscopy. Compared with pure g-C3N4, the composite showed increased photocurrent under UV irradiation, and overall significantly improved photocatalytic performance. Photocatalytic experiments showed specifically the composite made of a ZnO-to-g-C3N4 mass ratio of 3 : 1 displaying the best catalytic performance. The yields of CO and CH4 under UV irradiation were, respectively, 13.4 times and 49.7 times that of g-C3N4. In addition, a direct Z-scheme electron transfer mechanism was proposed to possibly play a large role in reducing charge recombination and to effectively improve photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional (2D) photocatalyst by the BiOCl ultrathin nanosheet modification of biochar (derived from biomass bamboo leaves) was successfully prepared via a facile one-pot hydrothermal process. The synthesized C/BiOCl photocatalysts showed a satisfactory performance on the degradation of tetracycline hydrochloride (TC-HCl). The enhanced photocatalytic activity originating from the introduction of biochar facilitated the rapid transfer of electrons generated from the defect states of the BiOCl ultrathin nanosheets. Moreover, the more the photo-electrons transferred in biochar, the more the quantities of active ˙O2− generated during the photocatalytic reaction, which was confirmed from the free radical capture tests. This work can be extended to the modified routes of BiOCl in the further applications of environmental wastewater treatments. [ABSTRACT FROM AUTHOR]

A novel biomass carbon quantum dots@Bi2WO6 (BC-QDs@Bi2WO6) photocatalyst with uniform dispersivity was prepared via a dialysis-assisted hydrothermal process. Multiple techniques including HR-TEM, XPS, UV-Vis, PL, photocurrent analysis, and electrochemical impedance spectroscopy were employed to investigate the morphology and structures as well as the optical and electronic properties of the as-prepared samples. The photocatalytic activity of BC-QDs@Bi2WO6 was assessed by the degradation of antibiotics (tetracycline, ciprofloxacin, and gatifloxacin). The improved photocatalytic activity was attributed to the quantum effect of BC-QDs, which acted as the light harvesting center, electron reservoir, and reaction center for degrading the pollutants. Furthermore, a plausible mechanism for photocatalysis was put forward according to the ESR and quenching experiments. The present work can have significant advantages in the construction of biomass carbon-based photocatalysts in pollutant degradation and improved light utilization. [ABSTRACT FROM AUTHOR]

Accurate prediction of ammonia nitrogen (NH 3 –N) in water was crucial to efficient and reasonable judgment of water quality and environmental conditions. A model named SCWT-IWOA-SVR was proposed in this study by combining synchronous compressed wavelet transform (SCWT), improved whale optimization algorithm (IWOA) and support vector regression (SVR). Firstly, the SCWT algorithm was used to de-noise the original data, overcome the nonlinearity of the data, and explore the variation rule of the water quality index time series. Statistical methods and Pearson correlation analysis were then used to select features. IWOA was introduced to optimize the hyperparameters in SVR kernel function, tent mapping was used to randomly initialize the location of the whales, making them more evenly distributed, combined wheel selection mechanism was used to select more representative prey, which leading to improve the accuracy of forecasts results. The results indicated that the SCWT-IWOA-SVR model, which incorporates synchronous compression wavelet transform and the improved whale optimization algorithm, exhibit a better prediction effect compared with SVR, WOA-SVR, WOA-SVR, and Random Forest (RF) models. The results indicated that the model has a good prediction performance of low error and high generalization (RMSE = 0.055, MAE = 0.015, R2 = 0.989), the RMSE <0.2 and R2 > 0.915 of the proposed SCWT-IWOA-SVR model in three days advance predicted. SCWT-IWOA-SVR model can provide a scientific basis for the comprehensive treatment and decision-making of water pollutants in the watershed. • The SCWT method to the raw data and compressing the output and band-pass filtering to achieve data noise reduction. • The IWOA-SVR algorithm, algorithm overcomes the randomness of the initial population and improves the prediction accuracy., • Analysis of the correlation between the water quality parameters improve the adaptability of the model. • SCWT-IWOA-SVR have good prediction accuracy and robustness in time series water quality predict. [ABSTRACT FROM AUTHOR]

Abstract A direct and facile "bottom-up" approach was carried out to prepare nitrogen doped graphene quantum dots (NGQDs) under hydrothermal conditions. The as-synthesized NGQDs exhibited an excellent excitation-independent upconversion and downconversion photoluminescent (PL) behavior. And further, the NGQDs/BiVO 4 composite photocatalysts were also fabricated to investigate enhanced visible-light photocatalytic performance. The addition of NGQDs in the NGQDs/BiVO 4 could improve the photocatalytic performance, and the results indicated 5.0 wt% NGQDs/BiVO 4 composites showed the optimal photocatalytic performance. The quenching of effects of different scavengers demonstrated that superoxide radical played a major role in MB degradation. A possible mechanism that NGQDs could enhance the photocatalytic performance of NGQDs/BiVO 4 composites had been also proposed. It was estimated that the photocatalytic performance of the NGQDs/BiVO 4 composites for the degradation of MB under visible light could be primarily ascribed to upconversion PL character of NGQDs and the efficient separation of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

In this work, a novel, simple, economical and green carbon quantum dots (CQDs) were obtained by hydrothermal method using bamboo as a carbon source at the first time. In order to further the use of such CQDs, we reported the facile fabrication of CQDs/Bi 3 Ti 4 O 12 (BTO) nanosheets photocatalysts. The experimental results indicated that CQDs were successfully coupled with BTO nanosheets, exhibiting excellent photocatalytic activity than bare BTO. The improved photodegradation efficiency was attributed to the extended light absorption range, and increased separation rate of electron-holes pairs. At last, a possible photocatalytic mechanism was proposed. The design of such CQDs from the creature with semiconductor can be extended to photocatalytic systems. [ABSTRACT FROM AUTHOR]

This work reports the direct transformation of the biomass of bamboo into carbon spheres by two step hydrothermal carbonization (HTC) at 180–200 °C. Such carbon spheres have potential applications as electrode materials with excellent electrical conductivity and high chemical stability. The biochar spheres (BS) were modified via protonation of g-C3N4 to form non-metallic photocatalysts with a unique core–shell architecture. In the BS@g-C3N4 core–shell photocatalysts, the protonated g-C3N4 sheets were the main photocatalyst and the biochar spheres acted both as a reservoir and a sensitizer, and displayed outstanding light absorption in nearly the entire wavelength range, due to the narrower gap of the sp2 carbon cluster and large amounts of carbon clusters. Conversion of raw biomass into stable carbon materials under relatively mild conditions offers a promising route to overcoming the challenges in obtaining biochar materials with precisely controlled morphology. Building a green non-metallic photocatalyst is an environmentally friendly embodiment of this. [ABSTRACT FROM AUTHOR]

An ion-imprinted fluorescent polymer (referred to as CQD@SiO@IIP) is presented for recognition of lithium ion. The material is based on the use of carbon quantum dots (CQDs) and is prepared by a surface imprinting technique using benzo-15-crown-5 (B15C5) as the complexing agent, methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinker, 2,2-azobisisobutyronitrile (AIBN) as the radical initiator, and lithium ion as the template. After optimization of the detection conditions, the relative fluorescence intensity (F/F), best measured at excitation/emission wavelength of 360 nm/460 nm, varies linearly with the Li concentration in the range between 0.5 and 50 μmol·L, with a limit of detection of 16 μmol·L. Performance was compared to the non-imprinted material, and the imprinting factor is found to be 4.5. The ion-imprinted fluorescence material was applied to the determination of Li in (spiked) water samples and obtained good recoveries ranged from 102 to 111.6%. [ABSTRACT FROM AUTHOR]

[Display omitted] • The bio-based modifier DL for promoting the comprehensive properties of PLA was designed and prepared using diethylenetriamine penta-(methylenephosphonic) acid and lysine in water phase without any organic solvent; • 6 wt% DL and 4 wt% polyethylene glycol (PEG) endowed PLA with UL94 V-0 rating and limited oxygen index (LOI) value of 29.4%; • DL performed its flame retardant role in PLA by both gas and condensed mechanism simultaneously; • The crystallinity degree of PLA with 6 wt% DL and 4 wt% PEG were improved to 39.0%; • The degradation of PLA in the purified water at the ambient temperature was accelerated by the addition of DL and PEG. Polylactide (PLA) as one of the excellent representative bioplastics had attracted attention worldwide. However, high flammability and poor crystallization behavior of PLA limit its further application. Moreover, the aqueous degradation rate of the pure PLA has been reported extremely low in natural environment (e.g. in water or soil). To solve these problems, the bio-based flame retardant DL was designed and prepared in water phase without any organic solvent by using lysine (Lys), derived from animals and beans, and diethylenetriamine penta-(methylenephosphonic) acid (DTPMPA), a non-toxic scale inhibitor for water treatment, as raw materials. The combination of the flame retardant DL and polyethylene glycol (PEG) endowed PLA with UL94 V-0 rating and limited oxygen index (LOI) value of 29.4%. The crystallinity degree of PLA with 4 wt% PEG and 6 wt% DL were improved to 39.0%. Moreover, the aqueous degradation of PLA in the purified water at the ambient temperature was accelerated by the addition of DL and PEG, manifested by the 38% decrease in M w of PLA. It is interested in the analysis of the degradation solution that the release of the oligomers of degraded PLA and the flame retardant DL was found during the aqueous degradation process, which further clarified the degradation mechanism. [ABSTRACT FROM AUTHOR]

In this paper, a novel Mn-doped CdS@NH 2 -MIL-125(Ti) (MC@NT) photocatalytic composites was synthetized through hydrothermal method. Hydrogen desorption and tetracycline and oxytetracycline degradation were performed under visible light to test their photocatalytic activities. The composites were characterized by XRD, FTIR, SEM, TEM, XPS, UV–Vis diffuse reflectance spectroscopy (DRS), EPR, EIS, and transient photocurrent response. From the characterization consequence, it could be seen that Mn-doped CdS was tightly attached to the surface of tetragonal NT in the form of nanoparticles. The MC@NT composites exhibited more promising catalytic activity than pristine monomeric materials. The photocatalytic hydrogen evolution rate reached 3.61 mmol g−1 h−1. Within 110 min, the degradation efficiencies of TC and OTC were 90% and 88%, respectively. The free radical trapping experiments proved that ·O 2 − and h+ were decisive role for degrading pollutants in the degradation catalysis process. Radical trapping experiments and electron spin resonance (ESR) indicated that the Z-scheme heterojunction was formed between Mn-doped CdS and NT, leading to facilitate the migration and shift of photogenerated carriers and holes. Cycling experiments showed that the as-prepared composites have good stability and have good prospects for practical applications. We believe this work will offer new ideas on the future development of efficient heterojunction catalysts for light energy conversion and other applications. [Display omitted] • Z-type CdS@NH 2 -MIL-125(Ti) photocatalysts were fabricated. • CdS@NH 2 -MIL-125(Ti) has the dual functionality of photocatalytic hydrogen evolution and antibiotic degradation. • The prepared composite material has significantly enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

The ternary conductive Ppy@Ag/g-C 3 N 4 composite photocatalysts was successfully synthesized by polymerization process and surface polymerization technique. And the as-prepared Ppy@Ag/g-C 3 N 4 sample exhibited the higher photocatalytic activity for various pollutant (MO, DM, TC, CIP, GFLX and EH) remove than that of pure g-C 3 N 4 and Ag/g-C 3 N 4 under visible light irradiation. It mainly originated from the Ag nanoparticles anchored between g-C 3 N 4 and Ppy acted as electron transfer mediator that facilitated the charge carrier separation and then expending the lifetime of the carriers. Meanwhile, the obtained Ppy@Ag/g-C 3 N 4 sample also showed a relatively good recycling stability which was the crucial factor for photocatalyst practical application. This work provided a new facile strategy for improving photo-degradation activity of g-C 3 N 4 photocatalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design of a Bi 2 O 3−x /NiAl-LDH S-scheme heterojunction to promote the separation of carriers. • Utilizing the LSPR effect to boost photothermal-assisted photocatalytic CO 2 reduction. • The introduction of Bi 2 O 3−x extends the photoresponse to long wavelength region. In this study, a new type of 2D/2D Bi 2 O 3−x /NiAl-LDH (BO/NA-LDH) S-scheme photocatalyst was prepared by combining NiAl-LDH with Bi 2 O 3−x by wet chemical deposition for obtaining efficient photothermal-assisted photocatalytic reduction of CO 2 under simulated sunlight irradiation. In particular, the as-prepared optimal 50-BO/NA-LDH sample exhibited the CO production yield of 83.55 ± 2.76 μmol/g/h, which was 9 and 27 times that of BO (9.32 ± 0.62 μmol/g/h) and NA-LDH (3.09 ± 0.38 μmol/g/h), respectively. The enhancement of photothermal-assisted activity over the 50-BO/NA-LDH system was mainly attributed to the coupling of the photothermal conversion performance of Bi 2 O 3−x and improving the migration efficiency of interface carriers of S-scheme heterojunction and 2D/2D structure. This study presents a promising strategy for the development of high-efficient photothermal-assisted photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mott Schottky junction is introduced into the traditional Z-scheme heterojunction. • The high conductivity of MXene improves the transport of photogenerated electrons. • Accelerated spatial charge separation and transfer on pCN/TC and TC/Sn-Bi-MOF interfacial Schottky junction. • The photocatalytic products are highly selective for CO production. a simple electrostatic self-assembly method is adopted, in which the Z-scheme heterojunction is directly constructed with Sn-Bi-MOF (SBM) using g-C 3 N 4 (pCN) as the support platform, and the Mott Schottky junction is introduced into the heterojunction (pCN/TC/SBM). This structure not only achieves efficient and stable CO 2 conversion, besides has a high degree of selectivity for CO due to the enhanced electrodynamic migration. Under simulated sunlight, pCN/TC/SBM showed high photocatalytic activity, and the amount of CO produced was 36.33 μmol·g−1·h−1, which was 4.36 and 3.5 times that of pCN and SBM, respectively, and the quantum apparent efficiency (AQY) was 3.2 % at 420 nm. The design method not simply improves the separation of electron-hole pairs, moreover accelerates the electrodynamic migration process, which increases the yield and improves the selectivity for CO. UPS, XPS, VB, DRS, ESR and work functions were used to analyze the Fermi level arrangement and band bending of the catalyst, and the photocatalytic mechanism and electron migration path were speculated. In situ FTIR is used to illustrate the specific path of the reaction. This work provides a new strategy for the design of heterojunctions and the enhancement of the yield and selectivity of carbon dioxide reduction products. [ABSTRACT FROM AUTHOR]

• Z-type heterojunction of Bi-Cu-x was prepared via an in-situ solvothermal method. • Intimate contact between Bi 2 Sn 2 O 7 and Cu 2 O accelerated charge transfer. • DFT calculations confirm the band structure and electron migration path of the material. • Bi-Cu2 can effectively handle actual water samples and present good stability. • The removal mechanism, degradation pathway and toxicity of TC were discussed. Tetracycline (TC) contaminants have garnered significant attention in aquatic environments due to their potential impact on human health and their persistent presence over extended periods of time. Photocatalysis is a highly promising method for purifying contaminated water bodies using light energy. The present study investigated the viability of utilizing a Bi 2 Sn 2 O 7 /Cu 2 O Z photocatalyst for the remediation of water contaminated with tetracycline. When the precursor body copper chloride dihydrate content was 0.15 g and bismuth stannate doped with 0.10 g (Bi-Cu2), the combination showed the best effect on tetracycline removal. The photocatalytic reaction rate was 1.83 times that of Cu 2 O and 17.50 times that of Bi 2 Sn 2 O 7 , respectively. The findings from electron spin resonance (ESR), free radical trapping experiments, high-performance liquid chromatography-mass spectrometry (HPLC-MS), T.E.S.T toxicological estimation, and density functional theory (DFT) calculations demonstrated that the in-situ anchoring of Bi 2 Sn 2 O 7 at Cu 2 O facilitated the development of a non-uniform electric field. Furthermore, the complex actual water body still maintained an outstanding removal effect, thereby confirming the practicality of using Bi-Cu2 to treat tetracycline in real water bodies under sun radiation. [ABSTRACT FROM AUTHOR]

The graphitic carbon nitride (g-C 3 N 4 ), as one photocatalyst which possess the suitable band gap, is better for modified TiO 2 and enhanced photocatalytic degradation of organic pollutants. In this work, the g-C 3 N 4 /TiO 2 were successfully prepared via directly calcined the mixture of melamine and P25. The as-prepared g-C 3 N 4 /TiO 2 photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and high resolution electron microscopy (HRTEM), Raman and Fourier transform-infrared spectroscopy (FT-IR). The photocatalytic performances of g-C 3 N 4 /TiO 2 composites were investigated by degradation of ciprofloxacin. The results showed that the g-C 3 N 4 and P25 were successfully composited, and the bond of C–N was well formed, the calcined temperature for as-prepared photocatalysts and the ratio of melamine and P25 were important to the degradation rate of ciprofloxacin. When the mixture of melamine and P25 with 1:2, and calcined temperature at 600 °C, the degradation rate of ciprofloxacin could reach 95% in 60 min. The enhanced photocatalytic performances could be mainly attributed to the suitable band gap structure with heterojunction of CN-P25. Finally, the possible transferred processes of photoelectrons and photoholes were proposed. [ABSTRACT FROM AUTHOR]

The modification of photocatalyst was the vital task for improving photocatalytic performance. Inspired by multi-level effect and activation regions of N atom, multi-level bismuth-based spheres (Bi2Ti2O7) and N-doped graphene quantum dots (N-GQD) were constructed for the photocatalytic application. Experiments demonstrated that the N-GQD/Bi2Ti2O7 multi-level spheres showed higher photocatalytic performance due to the multi-level effect and activation regions. Meanwhile, a series of characterizations proved that the separation efficiency of electron–hole pairs was improved after the N-GQD modifications. A possible mechanism was proposed for investigating N-GQD/Bi2Ti2O7 materials in the photocatalytic field. A novel N-GQD modified multi-level Bi2Ti2O7 spheres exhibited higher photocatalytic activity due to efficient electron transfer via N atoms. [ABSTRACT FROM AUTHOR]

A new-type photocatalyst of cadmium sulfide carbon nanotubes (/CNTs) was prepared by the hydrothermal method. This as-prepared /CNTs composite photocatalyst was proved to exhibit an excellent photocatalytic activity for degradation of tetracycline (TC). Specially, the 95%--5%-CNTs composite photocatalyst played the best degradation rate (81.2%) in 60 min under the visible light irradiation. Moreover, this 95%--5%-CNTs composite photocatalyst possessed great stability and could be used at least four cycles with almost no loss of photocatalytic efficiency. Furthermore, the as-synthesized /CNTs composite photocatalyst was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis diffused reflectance spectra (UV-Vis), Raman and thermal gravimetry (TG). In addition, the possible mechanism and kinetics of photodegradation of TC with /CNTs photocatalyst was also discussed. The mechanism of the photodegradation process on the CdS/CNTs photocatalyst is shown. It can be found that CNTs not only suppress the photogenerated carrier recombination as an electron-transfer and acceptor, but also stabilize CdS in the solution. As the photogenerated electrons undergo such an interfacial electron transfer process, the recombination process of the electrons and holes are hindered, which improves the photocatalytic activity of the CdS Quantum Dots on the tetracycline under the visible light irradiation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell Mn 3 O 4 @CIS microspheres were fabricated via in situ growing CIS on the surface Mn 3 O 4. • The charge transfer of Mn 3 O 4 @CIS followed the S-scheme route to achieve strong photocatalytic reduction and oxidation. • Mn 3 O 4 @CIS showed strong photocatalytic activity for pure water cracking hydrogen production. • The spherical core–shell heterostructure could widen the light absorption range and improve the electron-hole separation efficiency. In this study, core–shell Mn 3 O 4 @CdIn 2 S 4 (Mn 3 O 4 @CIS) microspheres were prepared via synthesis of Mn 3 O 4 microspheres with Mn-MOF as precursor followed by in-situ growth of CdIn 2 S 4 (CIS) shell. The hydrogen evolution rate of the optimized Mn 3 O 4 @CIS was 2.6 mmol·g−1·h−1, which were 11.54-fold and 17.44-fold that of CIS and Mn 3 O 4 alone, respectively. The spherical core–shell structure could broaden the light absorption range and enhance the separation and migration of photogenerated carriers, thereby promoting solar energy utilization. More importantly, experimental and computational results proved that the charge migration followed an S-scheme transfer route in the interface between Mn 3 O 4 and CIS, accumulating photogenerated electrons in the conduction band of CIS for robust photocatalytic hydrogen evolution. This work provided a facile strategy for the design and fabrication of efficient photocatalysts via synchronous morphology and S-scheme heterojunction architecture. [ABSTRACT FROM AUTHOR]

In this paper, coupling MoP onto ZIS surface using solvothermal method to form ohmic heterojunction. The photocatalytic performance of ZIS/MoP is significantly better than that of ZIS and MoP monomers, and the hydrogen evolution efficiency of the composite material reaches 2.031 mmol g−1 h−1, 50 and 18 times the hydrogen production efficiency of MoP and ZIS. The quantum apparent efficiency (AQE) reaches 10.5 %. The improvement of the photocatalytic performance of ZIS/MoP is attributed to the generation of Ohmic heterojunctions. An Ohmic heterojunction is formed when MoP attaches to the surface of ZIS as an electron acceptor, In one aspect, the electron transfer path of Ohmic heterojunctions improves the separation efficiency of electrons and holes, enhances the charge transfer efficiency. ln the other aspect, ZIS greatly improves the visible light absorption of ZIS/MoP. To confirm the photocatalytic mechanism and Ohmic heterojunction structure, characterization methods such as X-ray photoelectron spectroscopy (XPS), ultraviolet electron spectroscopy (UPS), and band structure were used. This study aims to improve photocatalytic performance by designing and constructing ohmic heterojunctions, and provides a new design approach for improving photocatalytic performance. [ABSTRACT FROM AUTHOR]

Building efficient catalysts is an urgent issue in the field of photocatalytic CO 2 reduction, and Z-scheme heterojunction structures can availably suppress the recombination of photo generated carriers and improve photocatalytic performance. This study successfully prepared a new type of Bi 4 O 5 Br 2 /Bi-MOF composite photocatalyst through self-assembly method. After 5 h of simulated sunlight exposure, the optimized sample 50-Bi 4 O 5 Br 2 /Bi-MOF photocatalytic reduction of CO 2 to CO efficiency (23.78 μmol·g−1·h−1) was 5.09 times higher than pure Bi 4 O 5 Br 2 , and the CH 4 yield (5.39 μmol·g−1·h−1) was 2.52 times that of pure Bi-MOF. In addition, in the cyclic experiment, the catalyst had high stability and reusability. The Z-scheme charge transfer mechanism was confirmed through band structure analysis, Electron spin resonance (ESR), Ultraviolet photoelectron spectroscopy (UPS) and other related characterizations. This work provided an important strategy for designing efficient Z-scheme heterojunction photocatalysts. [Display omitted] • Construct Bi 4 O 5 Br 2 /Bi-MOF Z-scheme heterojunction to improve reduction performance. • Bi 4 O 5 Br 2 /Bi-MOF composite photocatalyst exhibits excellent chemical stability. • The reaction intermediates were analyzed using in-situ infrared spectroscopy. • Proving the formation of Z-scheme heterojunction through series characterizations. [ABSTRACT FROM AUTHOR]

The Ag/BiOI/C composite photocatalyst was synthesized by high-temperature tube furnace calcination method. The Ag/BiOI/C (0.5:2:3) sample showed the greater competence for the photocatalytic remove of the typical methylene blue dye compared with the pristine BiOI and BiOI/C under visible light exposure. The characterization was confirmed the Ag and C could synergistically enhance the photocatalytic performance. Among, the Ag and C worked as electron acceptors enhanced separation effectiveness of photo-induced electron-hole pairs and suppressed their recombination. Further, trapping experiments displayed that the ·O2− and h+ were the major function in the photo-degradation of methylene blue. A possible mechanism was proposed for the novel photocatalyst. The SPR effect and biochar were used to synergistically enhance the photocatalytic activity of BiOCl flower. [ABSTRACT FROM AUTHOR]

• LSPR effect enhanced Z-scheme ZnO/Au/g-C 3 N 4 micro needles film (3-ZAC) has been prepared for the photoreduction of CO 2 into CO under UV–vis light irradiation. • Au NPs at the interface of ZnO/g-C 3 N 4 not only act as the electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs photogenerated in the semiconductors. • DFT calculation and FDTD simulation methods has been used to prove the transfer processes of photogenerated electron. The photoproduction of CO from the photocatalytic CO 2 reduction process has been evidenced from 13C isotope tracer tests. • This work demonstrates the importance of the build-in electric field formed at g-C 3 N 4 /ZnO interface and local electromagnetic field of Au NPs for the photoreduction process, providing an inspiring concept for future advancement in this area. Local Surface Plasma Resonance (LSPR) effect enhanced Z-scheme ZnO/Au/g-C 3 N 4 micro-needles film (3-ZAC) has been prepared for the photoreduction of CO 2 into CO under UV–vis light irradiation. Photoreduction experiments show that 3-ZAC has the excellent photocatalytic performance and reusability. The CO production can be achieved 689.7 μmol/m2 after 8 h reaction time, which is 4.5 higher than that of the pure ZnO film. 13C isotope test shows that CO is produced from CO 2 by photoreduction. DFT calculations confirm that build-in electric field formed at g-C 3 N 4 /ZnO interface effectively promoted the electron transfer efficiency in Z-scheme interface. FDTD simulations prove that Au NPs not only act as electron-transfer bridge, but also as LSPR excited source to speed up the separation of electron-hole pairs. In-situ FTIR technique was used to investigate the CO 2 photoreduction process. The above characteristics together maximize the electron transfer efficiency, which causes the material has enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

In this work, ZnSe/ZnCo 2 S 4 (ZCS) composites were synthesized by simple hydrothermal method and Z-scheme heterojunctions were formed. Under the simulated sunlight environment, The results show that the hydrogen production efficiency of 70 wt% ZnSe/ZCS composites was as high as 3402.4 μmol·g−1·h−1, which is 4.37 and 94.44 times that of ZnSe and ZCS monomers, respectively, and the apparent quantum efficiency (AQY) reaches 10.5%. Among them, the Z-scheme heterojunction improves the redox ability of the material, which is more conducive to charge separation, and ZCS also promotes absorption of visible light of ZnSe/ZCS. In addition, the Z-scheme heterojunction structure and material stability were verified by XPS, ESR.This work provides a new way to improve ZnSe in the field of photocatalytic hydrogen evolution. [Display omitted] • The Z-scheme heterojunction improve the utilization efficiency of charge and retain great redox capacity. • ZnSe/ZCS have excellent activity for photocatalytic hydrogen evolution. • The framework provided by ZCS allowed ZnSe to expose more active sites. • The composite photocatalysts owned excellent chemical stability. [ABSTRACT FROM AUTHOR]