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The midgap states and amino groups resulted from bulk phase N defects and surface C defects synergistically catalyze the photocatalytic reduction of CO 2 to hydrocarbon fuels. Defect structure is one of the crucial factors for enhancing the catalytic activities of photocatalysts. However, rational design and construction of defect structures in catalysts to meet the aim of enhancing photocatalytic performance in a simple and cost-effective way is still a challenge. In this contribution, we report a strategy to construct defect structures in graphitic carbon nitride (g-CN) by simple copolymerizing of urea with polyethyleneimine (PEI). Among the prepared catalysts, u-0.05PEI presents the best photocatalytic activity for CO 2 reduction, with CO and CH 4 yields of 32.86 and 1.68 μmol g−1 in 4 h, which is about 3.2 and 2.5 times higher than that of g-CN, respectively. Characterization results show that both C and N defects are formed in the newly prepared catalysts. The C defects on the surface of u-xPEI result in the formation of more amino groups which are beneficial for CO 2 adsorption. Meanwhile, the N defects inside the samples lead to the generation of midgap states between the valance band and conduction band of u-xPEI. The midgap states greatly enlarge the light absorption extent, and enable the use of light with energy lower than the intrinsic absorption of g-CN in the photoreduction of CO 2. As confirmed by DRS, EPR, PL analysis, the excellent catalytic activity of u-0.05PEI is mainly attributed to the remarkably improved light utilization efficiency and fast charge transfer. Moreover, the reaction is performed in water without any additive or organic solvent, which makes it environmentally friendly. [ABSTRACT FROM AUTHOR]

• Oxygen vacancy-rich Bi 2 WO 6 /In 2 O 3 heterojunction is fabricated firstly. • The 80 wt% Bi 2 WO 6 /In 2 O 3 exhibits high photocatalytic activity for degrading pollutants. • OVs as extra electron transfer channel can promote carrier separation. • The synergy between OVs and heterojunction improves photocatalytic performance. • A possible mechanism of the enhanced photocatalytic efficiency is proposed. Photocatalysis is an attractive and green strategy for organic pollutant removal. The development of alternative and effective photocatalysts has attracted great attention. Herein, we rationally engineer an alternative rich-oxygen vacancies (OVs) Bi 2 WO 6 /In 2 O 3 composite photocatalyst via integrating the calcination and hydrothermal method for removing organic dyes (rhodamine B). Thanks to the synergistic effect of OVs and heterojunction structure, the 80 wt% Bi 2 WO 6 /In 2 O 3 (BiIn80) displays enhanced photocatalytic degradation effect. The degradation rate of BiIn80 is up to 97.3% under light irradiation within 120 min and the reaction rate constant k value (0.03221 min−1) is about 15-fold and 4.17-fold as high as those of In 2 O 3 (0.00203 min−1) and Bi 2 WO 6 (0.00772 min−1), respectively. The heterostructure of Bi 2 WO 6 /In 2 O 3 can extend the lifespan of the photogenerated charge carriers. Moreover, the density functional theory (DFT) calculations reveal that the OVs in Bi 2 WO 6 /In 2 O 3 can boost visible light absorbability by decreasing band gap value and serve as the extra electron transfer channels to enhance the separation efficiency of photogenerated electron-hole pairs. This study not only provides an alternative route for fabricating highly efficient heterojunction photocatalysts, but also obtains better understanding of the synergistic effect of OVs and heterojunction on enhancing the photocatalytic performance. [ABSTRACT FROM AUTHOR]

To completely utilize the high redox ability of photo-induced charge carriers. Here, a Z-scheme photocatalyst of TiO 2 QDs/Bi 12 TiO 20 (TBT) composites with TiO 2 QDs fragment attached to the surface of Bi 12 TiO 20 (BTO) was prepared and the photocatalytic activity was evaluated by degradation of gatifloxacin (GF). The optimal photocatalytic performance of TBT displayed 3 times higher than bare BTO. The improved photocatalytic performance was ascribed to the effective separation of the charge carriers between TiO 2 QDs and BTO via the direct Z-scheme heterojunction. Such a strategy for the construction of Z-scheme TBT composites for removal of organic pollutants, proving new insights into design photocatalyst. • A TiO 2 quantum dots fragment was prepared and covered on the surface of Bi 12 TiO 20. • A Z-scheme heterojunction was formed between TiO 2 QDs and Bi 12 TiO 20. • The TOQs played as the sensitizer to increase the photocatalytic activity. [ABSTRACT FROM AUTHOR]

In this work, a biofiber was used as the natural polymer carrier to design a BiVO 4 QDs/cellulose fiber composite for photocatalytic application. The biofiber was obtained from bamboo, which was green, abundant and short growth cycle in Asia. Naturally rich groups of biofiber provided many sites to absorb the Bi3+ to form the uniform distribution for BiVO 4 QDs. Moreover, a series of results indicated the strong connection was formed between biofiber and BiVO 4 QDs, which could increase the stability and electron transfer. Therefore, the new composite photocatalyst exhibited better stability and effectively photocatalytic activity. Moreover, the possible mechanism of synthesis and photocatalytic were discussed, which provided insight for synthesizing photocatalytic based on biomaterials. Extracting cellulose fiber of bamboo to designed a novel BiVO 4 QDs/fibers composite photocatalyst via the in-situ method, which showed an enhanced stability and photocatalytic activity. Image 1 • Bamboo as the source to prepared cellulose fibers due to its abundant and short growth cycle. • A novel BiVO 4 QDs/fibers composite photocatalyst was obtained via the in-situ method. • Rich groups of natural cellulose fibers provided many sites to form the stability and distribution BiVO 4. • The mechanism of synthesis and the photocatalytic process were discussed and proposed. [ABSTRACT FROM AUTHOR]

2D/2D heterojunction photocatalyst of CdIn 2 S 4 on nitrogen doped reduced graphene (N-rGO) was fabricated by in situ hydrothermal method. It is noticeable that the flower-like CdIn 2 S 4 photocatalyst composed of film is controlled by the temperature of synthesis process. When CdIn 2 S 4 photocatalyst load on N-rGO, irregular film N-rGO functions as support to disperse the CdIn 2 S 4 , forming the 2D/2D interfacial structure, which is confirmed by SEM, TEM and HRTEM. When the mass fraction of N-rGO is 10%, the binary composite photocatalyst could photodegrade 80% 50 mg/L 2,4-dichlorophenol (2,4-DCP). That is because the heterojunction formed between CdIn 2 S 4 and N-rGO promotes the electron transfer, especially the interfacial contact region. What's more, the N-rGO can efficiently accumulate the 2,4-DCP molecules because of its unique structure, bettering the contact rate between 2,4-DCP and the whole photocatalyst. The possible mechanism of photodegrading 2,4-DCP was discussed and investigated. This work highlights the synergistic effect, especially the harmony between charge transfer and active sites to benefit the photocatalytic performance. A schematic of possible photocatalytic mechanism. Image 1 • 2D/2D CdIn 2 S 4 /N-rGO interfacial heterojunction photocatalyst was obtained by in situ hydrothermal method. • The as-prepared 2D/2D CdIn 2 S 4 /N-rGO materials exhibited extensively enhanced photocatalytic activity for the degradation of 2,4-DCP under visible light irradiation. • The possible process about irregular and looser CdIn 2 S 4 nanosheets formed was given. • Intimate 2D interfacial heterojunction gives more channels to transfer photogenerated carries and N-rGO supplies active sites, bettering photocatalytic performance. A possible mechanism of 2D/2D CdIn 2 S 4 /N-rGO photocatalyst for the enhancement of visible light performance was proposed. [ABSTRACT FROM AUTHOR]

The kernel of photocatalytic technology is to exploit photocatalytic materials with high efficiency, stability and easy recovery. Herein, we designedly prepare a magnetic quantum dot (Fe 3 O 4 QDs) as co-catalyst to modify Z-scheme Bi 2 O 4 /g-C 3 N 4 (Bi/CN) composite photocatalyst via combining calcination with hydrothermal method. The morphology, chemical composition and physicochemical properties of photocatalysts are systematically analyzed by a series of characterization means. The experimental results explicitly render that the optimum Fe 3 O 4 -QDs/Bi 2 O 4 /g-C 3 N 4 (FeQDs/Bi/CN) has outstanding photocatalytic performance than that of Bi 2 O 4 , g-C 3 N 4 and Bi 2 O 4 /g-C 3 N 4 (Bi/CN), which is chiefly imputed to the synergistic effect of Z-scheme heterojunction system and Fenton reaction. The Z-scheme heterojunction is conductive to accelerate charge carrier separation and makes electrons and holes retain higher redox ability. Fe 3 O 4 QDs can promote visible light absorption and generate more hydroxyl active (OH) substances through Fenton reaction. Furthermore, the magnetic photocatalyst is liable to separate under the action of external magnetic field, which ensures that is convenient for industrial application. The mechanism of photocatalytic degradation is discussed in detail by capturing experiments, ESR and liquid fluorescence detection. This work unveils more possibilities for modifying Z-scheme heterojunction system to improve photocatalytic performance. Unlabelled Image • An original FeQDs/Bi/CN is constructed via facile calcination-hydrothermal method. • The FeQDs/Bi/CN has excellent photocatalytic activity for degrading pollutants. • Fe 3 O 4 -QDs make photocatalysts have excellent OH productivity and light absorption. • The OH plays a major role in photocatalytic degradation of pollutants. • The possible mechanism of photocatalytic reaction is discussed in detail. [ABSTRACT FROM AUTHOR]

This study aimed to regulate the band structure and enhance the reduction ability of CdS by substituting it with Mn2+. Subsequently, this nano MnCdS solid solution was anchored on the surface of truncated octahedral Cu 2 O through a simple hydrothermal process, forming an S-scheme heterojunction at the interface between MnCdS and Cu 2 O. Equilibrating the Fermi level at the MnCdS/Cu 2 O heterojunction led to spontaneous diffusion of electrons in MnCdS to Cu 2 O, generating an internal electric field that drove the recombination of electrons in the conduction band (CB) of Cu 2 O and holes in the valence band (VB) of MnCdS. Consequently, this process preserved the powerful photogenerated electrons in the CB of MnCdS, facilitating robust photocatalytic hydrogen evolution. The MnCdS/Cu 2 O exhibited a photocatalytic hydrogen evolution rate of 66.3 mmol g−1 h−1, which was 3.4- and 54.3-times higher than that of MnCdS (19.4 mmol g−1 h−1) and Cu 2 O (1.2 mmol g−1 h−1), respectively. This study elucidates advanced S-scheme heterojunction catalyst architectures for photocatalytic hydrogen production. [Display omitted] • 0D/3D Mn-doped CdS/Cu 2 O are prepared through a simple one pot method. • Mn2+ doping leads to extensive light absorption and higher reduction potential to achieve effective charge carrier separation and transport. • S-scheme heterojunction retains the strong photogenerated electrons in the CB of MnCdS/Cu 2 O for robust photocatalytic hydrogen release. • The optimized MnCdS/Cu 2 O exhibited hydrogen release rate of 66.3 mmol g−1 h−1. [ABSTRACT FROM AUTHOR]

Designing and developing an efficient photocatalytic system for degrading organic pollutants was a research hotspot in the field of environmental governance. In this study, a novel Bi 2 WO 6 /In(OH) 3 composite photocatalyst was first fabricated via facile calcination-hydrothermal synthesis method. The 9-Bi 2 WO 6 /In(OH) 3 composite had superior photocatalytic performance for degrading the 2-Mercaptobenzothiazole (MBT) under visible-light irradiation. The degradation rate constant of 9-Bi 2 WO 6 /In(OH) 3 was 0.02192 min−1, which was 2.3 times than that of pure Bi 2 WO 6 (0.00948 min−1). The improvement in photocatalytic performance was due to the synergistic effect of the surface heterojunction and the electron-transfer medium. The density functional theory (DFT) showed that the difference in energy levels between the conduction bands and valence bands of Bi 2 WO 6 nanocubes (010) and (001) could build the surface heterojunction, which was in favor to promote the electron-hole pairs separation. And the In(OH) 3 not only acted as a supporter to prevent the agglomeration of small size Bi 2 WO 6 nanocubes, but also served as electron-transfer mediator to inhibit the recombination of electrons and holes. This study provided a reference value for the development and utilization of Bi-based photocatalysts. Considering the properties and structural characteristics of Bi-based photocatalysts and hydroxides, Bi 2 WO 6 /In(OH) 3 composite photocatalysts were design reasonably, which provided a variety of the types of photocatalysts. Unlabelled Image • The unique Bi 2 WO 6 /In(OH) 3 photocatalyst was constructed via facile calcination-hydrothermal synthesis method. • The 9-Bi 2 WO 6 /In(OH) 3 showed excellent photocatalytic performance for the degradation of TC, Cr(VI), RhB and MBT. • The small size Bi 2 WO 6 nanocubes could form the surface heterojunction between (001) and (010) was proved by DFT. • The synergistic effect of surface heterojunction and electron-transfer mediator enhanced the separation of carriers. • The possible photocatalytic degradation mechanism of 9-Bi 2 WO 6 /In(OH) 3 was proposed. [ABSTRACT FROM AUTHOR]

Abstract In this work, two Bi-based semiconductors composites was synthesized through the BiVO 4 quantum dots (BVO QDs) was grown on the Bi 12 TiO 20 (BTO) via an in-suit growth with the ultrasonic method, which was more stability and evenly dispersed. As expected, the BVO-BTO composites exhibited increased visible-light-driven photocatalytic performance for photo-degradation due to the advantages of BVO QDs. Moreover, the possible mechanism of BVO-BTO composites was studied by trapping experiment, photocurrent, UV–vis and so on. The results demonstrated that the BVO QDs can widen the light response range to visible region and hasten the charge transfer and separation. Thus, the photocatalytic activity was enhanced through the BVO QDs decorated on BTO, which provided a new idea for designing Bi-based materials. Highlights • Two Bi-based materials were used to design the BiVO 4 quantum dots/Bi 12 TiO 20 composites. • The in-suit growth with the ultrasonic method was benefit to stability and dispersed. • The BVO-BTO composites have a better light response and electron transfer. [ABSTRACT FROM AUTHOR]

Abstract In this work, a simple method to load of g-C 3 N 4 quantum dots (CN QDs) onto Bi 2 Ti 2 O 7 (BTO) microsphere with the amount of CN QDs (3, 7, 10 and 15%). The photocatalyst was used for the treatment of water pollutants under visible-light illumination, which proved that CNBTO composites showed improved photocatalytic activity matched up to pure BTO. Reformation of BTO with CN QDs enhanced the light assimilation capacity, and promoted the isolation of photo-induced electron-hole pairs. The trapping experiments and ESR were announced the holes (h+) and superoxide oxide (O 2 −) played the key role, and the relative mechanism of the photocatalytic process was proposed. Meanwhile, the effects of CN QDs content, pH and initial pollutant concentration on the removal efficiency of ciprofloxacin (CIP) were studied. Results showed that the CN QDs loaded on BTO presented higher photocatalytic efficiency, and an optimum value for the dosage of photocatalytic in pH 8.0. Graphical Abstract The g-C 3 N 4 quantum dots modified Bi 2 Ti 2 O 7 microsphere for enhancing separation efficiency of electron-hole pairs. Unlabelled Image Highlights • The CN QDs have superior electron transfer ability and enriched light harvesting. • The CN QDs were coupled with Bi 2 Ti 2 O 7 microsphere have exhibited enhanced photocatalytic activity. • The CN QDs extends the light absorption of Bi 2 Ti 2 O 7 microsphere. [ABSTRACT FROM AUTHOR]

Abstract Many recent advances in constructing green metal-free materials have opened new possibilities in catalysis. To explore and enhance the photocatalytic performance of g-C 3 N 4 quantum dots (CN QDs), the metal-free materials of CN QDs embedded in the h-BN was successfully synthesized by calcination the mixture of melamine and h-BN. The studies proved the CNBN has appeared red-shift due to the quantum size effect and 2D h-BN. The CN QDs were embedded into the h-BN could not only facilitate the separation and transfer, but also the h-BN terminated with OH groups could act as active sites, thus enhanced the photocatalytic performance. Moreover, this work may pave the way for the application of CN QDs and fabricate 2D h-BN composites for green metal-free materials in another field. Graphical abstract A free-metal composites for environmental pollution treatment. Unlabelled Image Highlights • A metal-free materials were synthesized by the one-pot green procedure. • The composites were exhibited red-shift for increasing light absorption. • The efficiency of electrons separation and transfer enhanced the lifetime of active species. • The OH groups acted as active sites further improved the photocatalytic performance. [ABSTRACT FROM AUTHOR]

The construction of a heterojunction is an effective way to improve the photocatalytic activity of a semiconductor. In this study, to improve the photocatalytic activity of BiPO4 in visible light and the quantum yield of In2S3, a novel In2S3/BiPO4 heterojunction photocatalyst was successfully synthesized via a solvothermal method. XRD and TEM characterizations reveal that In2S3 was irregularly loaded on the surface of BiPO4, leading to good dispersion of In2S3, greatly improving the catalyst active site. Meanwhile, In2S3 also greatly improves the visible light absorption of BiPO4. An ESR spin-trap technique and trapping experiments on active species indicate that ṖO2− and h+ are the main activated species during the photodegradation process. Finally, the as-obtained In2S3/BiPO4 heterojunction exhibits higher photocatalytic activity than those of pure In2S3 and BiPO4 for the photodegradation of rhodamine B (RhB) and tetracycline (TC). This work provides a promising way to photodegrade organic materials to reduce water pollution. [ABSTRACT FROM AUTHOR]

A novel Z-scheme CdS/Ag/g-C3N4 nanosheets photocatalyst was synthesized by combining the hydrothermal and photo-deposition techniques, where Ag nanoparticles as carrier transport channels significantly improve the separation efficiency of electron–hole pairs. Outstanding photocatalytic activity was observed, which indicates that the constructed Z-scheme can retain the oxidizing ability of the CdS valence band and reducing ability of the g-C3N4 conduction band. In addition, trapping experiments and ESR measurement reveal that the superoxide radical (ṖO2−) and holes (h+) are the predominant active species. This study provides a new approach to perfect the Z-scheme photocatalytic system for application in the efficient treatment of persistent pollutants in wastewater. [ABSTRACT FROM AUTHOR]

A series of hamburger-like Ag@ZnO/C core–shell plasmonic photocatalysts have been synthesized via a simple solvothermal method for degradation of tetracycline (TC) under visible light irradiation, possessing high photocatalytic activity and good stability. The presence of localized surface plasmon resonance (LSPR) in the Ag core has increased the photocatalytic activity over an extended wavelength range. The plasmon-induced resonant energy transfer (PIRET) and direct electron transfer (DET) have facilitated the excitation and separation of photogenerated e−/h+ pairs, which has been further confirmed by electrochemical investigations. The presences of hydroxyl radicals (⋅OH), superoxide radicals (⋅O2−) and singlet oxygen (1O2) in the photocatalytic reaction system of Ag@ZnO/C photocatalyst have been demonstrated by electron spin resonance (ESR) measurements. All of the experiment results indicate that the ternary structure of Ag@ZnO/C can effectively enhance the photocatalytic activity. Furthermore, the effects of introduced Ag contents and carbon source dosage were researched by comparative photocatalytic experiments, and the potential structures of photodegradation products were studied by HPLC-MS. A series of hamburger-like Ag@ZnO/C plasmonic photocatalysts was synthesized. The photocatalysts exhibited great photocatalytic activity and stability, and the PIRET and DET have facilitated the excitation and separation of charges. The possible photodegradation mechanism was systematically presented and the potential structure of new photodegradation products was studied. [ABSTRACT FROM AUTHOR]

One of current ideal thought to reduce the recombination of photogenerated electrons and holes from semiconductors is constructing Multi-dimensional semiconductor-carbon (S-C) heterostructures. As well as acting to photo-degrade the organic contaminant and decrease the toxicity, β-In 2 S 3 is chosen as a potential semiconductors for photocatalysts. Relative good photocatalytic properties delivered on β-In 2 S 3 , however, the fast recombination of photogenerated charge carriers are often appeared, causing reduced further application. Carbon quantum dots (CQDs) involve the introduction of plasma effect into the zero-dimensional nanomaterials in order to arouse an effect: either promoting the charge carriers transfer or plasma energy conversion of the photo-excited CQDs. However, state of the two components also encompass the poor quantum yield existed in the CQDs by its serious agglomeration. Thereby, the delivery of extraordinary ballistic electrical and thermal conductivity on single-walled carbon nanotubes (SWNTs), have shown potential for use in a variety of semiconductors decorating application. Herein, we show that a novel CQDs@In 2 S 3 /SWNTs composite in the Multi-dimensional (3D) hierarchical superstructures with an enhanced photocatalytic efficiency. The ESR analysis and free radicals trapping experiments indicated that the O 2 • − and h + were the main active species for the photocatalytic degradation. The potential photocatalytic mechanism of the three components is discussed and the direction in the plasma effect exhibited in CQDs is also considered, with a particular focus on photocatalytic area. [ABSTRACT FROM AUTHOR]

• BiVO 4 /MoS 2 @GO (MBG) is prepared by an in-situ hydrothermal method. • The optimal working conditions are determined by orthogonal analysis. • The heterojunction formed between BiVO 4 and MoS 2 promotes charge separation. • MBG photocatalytic degradation rate is 13 and 2.4 times higher than MoS 2 and BiVO 4. • Electron transmission channels promote the separation of photogenerated carriers. The low separation efficiency of photogenerated electron-hole pairs is the main factor that restricts the performance of photocatalysts. In this paper, BiVO 4 /MoS 2 @GO composites were synthesized by in-situ hydrothermal method, and the experimental conditions were optimized by orthogonal test to improve the separation rate of photogenerated electron-hole pairs. The as-prepared BiVO 4 /MoS 2 @GO composites exhibited a Z-scheme heterojunction, which effectively promoted photogenerated electron-hole pair separation. In addition, the separation rate of photogenerated electron-hole pairs was effectively improved by using graphene oxide nanosheets as electron transport channels. This enhanced the utilization rate of photogenerated carriers in the BiVO 4 /MoS 2 @GO composites, thus improving the photocatalytic activity. The photocatalytic tetracycline degradation rate of the as-prepared BiVO 4 /MoS 2 @GO in the best working conditions was 13 times and 2.4 times higher than that of MoS 2 and BiVO 4. This work provides new insight into the preparation of photocatalysts with an efficient electron transfer mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]

Imprinted modified POPD/CdS S-scheme heterojunction possesses good selective degradation ability and CdS photocorrosion resistance. [Display omitted] • IM-POPD/CdS S-scheme heterojunction is obtained by microwave polymerization technique. • Imprinted modified POPD layer inhibits CdS photo-corrosion. • S-scheme heterojunction formed by POPD and CdS improves the photocatalytic activity. • Imprinted modified POPD layer achieves the orientation degradation of DFM in different water environments. Imprinted modified poly-o-phenylenediamine (POPD)/CdS S-scheme heterojunction (IM-POPD/CdS) was synthesized by microwave polymerization method, which showed excellent CdS photocorrosion resistance and photocatalytic degradation performance towards danofloxacin mesylate (DFM). Interestingly, owing to the presence of imprinted cavities on IM-POPD/CdS, IM-POPD/CdS can selectively adsorb and degrade DFM. IM-POPD/CdS exhibited a good orientation degradation ability in different water environments. More importantly, due to the coating of the imprinted modified POPD layer and the consumption of h+ in the CdS valence band by e- on the POPD, the photocorrosion of CdS is greatly inhibited, and its secondary pollution is reduced. This study provides a new idea for photocorrosion resistant functional heterojunction materials and an exemplary way for the effective directional degradation of target pollutants. [ABSTRACT FROM AUTHOR]

N–ZnO/CdS/Graphene oxide (GO) composite photocatalysts have been successfully synthesized by hydrothermal method. The as-prepared composite photocatalysts were characterized by X-ray diffraction (XRD), Raman, scanning electron microscopy(SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), fourier transform infrared (FT-IR) spectra, UV–vis diffuse reflectance spectra (UV–vis DRS), thermogravimetry (TG) and photoluminescence (PL). The as-prepared photocatalysts exhibited strong visible light photocatalytic activity toward to degradation of antibiotics under ambient conditions. Particularly, the N–ZnO/CdS/GO composite photocatalysts showed the higher photocatalytic degradation rate (86%) of ciprofloxacin CIP under visible light irradiation than the pure photocatalysts. Compared with degradation of different antibiotics (tetracycline (TC), oxytetracycline hydrochloride (OTC-HCl) and levofloxacin (LEV)), the N–ZnO/CdS/GO composite photocatalysts also exhibited high photocatalytic activities. According to the experiments, the role of GO in the composite photocatalysts acted as an electron conductor, and also enhanced the separation rate of electrons and holes which greatly improved the photocatalytic activity. Lastly, the mechanism of enhanced photocatalytic degradation of CIP was also discussed. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) CdSe exhibits relatively high photocatalytic abilities for its unique properties, but the aggregation and photocorrosion have blocked its further application. Therefore, for arriving at a solution, alkaline earth metal ions (M = Mg 2+ , Ca 2+ , Sr 2+ and Ba 2+ ) and reduced graphene oxide (rGO) are chosen to fabricated new QDs CdSe-based photocatalytic systems. In this paper, M@CdSe/rGO composites have been synthesized via a facile one-step hydrothermal approach, during which the formation of M doped CdSe crystallization and GO reduction occur simultaneously. The obtained photocatalysts demonstrates synergistically enhanced visible light photocatalytic activity and stability toward photodegrading tetracycline hydrochloride (TC-HCl) solution, especially the introduction of 6 mol% Ca 2+ and 5 wt% GO on QDs CdSe resulted in 85.6% degradation of 15 mg/L TC-HCl in 1 h with 0.5 g/L catalyst. Furthermore, the photodegradation mechanism was systematically investigated by active species trapping experiment. It revealed that h + was the major active species in the destructions process. And the possible process of charge transfer for Ca 2+ @CdSe/rGO nanocomposite was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

• 1D II-OV-CdO 0.5 S 0.5 is synthesized S2- ion exchange assisted inorganic imprinting technology. • The e- is gathered near the oxygen defects around the imprinted cavities. • Orientation photocatalytic ability is enhanced by confining TC to the imprinted cavities. • Degradation of CIP is inhibited under the premise of enhancing the degradation of TC. [Display omitted] The conventional means for selectively capturing and subsequently degrading specific organic pollutants entails the development of an inorganic imprinted photocatalytic material with visible light response, high activity, and high stability. Hence, the inorganic imprinted oxygen vacancy CdO 0.5 S 0.5 (II-OV-CdO 0.5 S 0.5) was prepared by S2- ion exchange assisted inorganic imprinting technology. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD) patterns, X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR) and thermogravimetry analysis (TGA) were used to comprehensively prove that S element only permeated the surface of the material, and there were imprinted cavities and a few oxygen defects caused by inorganic imprinting. Photoelectrochemistry experiments and DFT theoretical calculation showed that the electrons gathered near the oxygen defects around the imprinted cavities (specific reaction sites), and the reactive center formed was more favorable to the specific adsorption of tetracycline (TC). Since TC was confined to the specific reaction sites enriched in electrons, the apparent rate constant of II-OV-CdO 0.5 S 0.5 (0.0220 min−1) was 2.18 times that of CdO 0.5 S 0.5 (0.0101 min−1) after TC photodegradation for 60 min under visible light. More importantly, although the space size of ciprofloxacin (CIP) was smaller than that of TC, because the imprinted cavities not only had a size effect, but also possessed the specific adsorption sites, there was no significant enhancement in the degradation of CIP. Therefore, II-OV-CdO 0.5 S 0.5 demonstrated excellent orientation photocatalytic ability for the target (TC), under the premise of improving the photodegradation of the target, II-OV-CdO 0.5 S 0.5 effectively inhibited the photodegradation of other reference pollutants. This work provides an exemplary method for the design of functionalized photocatalytic materials and the orientation removal of specific pollutants. [ABSTRACT FROM AUTHOR]

Imprinted P25@IL nanoreactor prepared in aqueous-phase via stable interaction forces between IL and LEV exhibited excellent selectivity and photocatalytic ability. [Display omitted] • Imprinted P25@IL nanoreactor is obtained by aqueous-phase microwave polymerization strategy. • The strong interactions between IL and LEV overcome the interference of water molecules. • Type II heterojunction formed between IL and P25 improves the photocatalytic activity. • Imprinted cavity enhances the selective degradation ability. Common molecular imprinted photocatalysts are usually prepared in highly toxic organic solvent medium, which will be disturbed by water molecules and swelling differences when used for selective recognition in the aqueous phase. In this study, an ionic liquid (IL) was used as the functional monomer and functionalized P25@IL heterojunction molecular imprinted photocatalytic nanoreactor, referred to as imprinted P25@IL nanoreactor, were prepared via the aqueous-phase microwave polymerization strategy. Imidazole-based IL cations can provide π electron clouds, and side chains are easily functionalized and modified, resulting in strong interactions such as π-π and ion dipoles being formed between IL and levofloxacin hydrochloride (LEV), which can overcome the interference of water molecules and achieve better selective adsorption and degradation of LEV in aqueous medium. The selectivity coefficient of imprinted P25@IL nanoreactor relative to P25 and functionalized P25@IL heterojunction molecular non-imprinted photocatalyst (non-imprinted P25@IL photocatalyst) were 2.69 and 2.26, respectively. More importantly, with the formation of IL-P25 heterojunction and surface imprinted layer, the photocatalytic performance of imprinted P25@IL nanoreactor was 2.33 times higher than that of P25. Our findings offer a novel approach to the synthesis of water-soluble functional monomers and the aqueous-phase synthesis of molecular imprinted photocatalytic materials. [ABSTRACT FROM AUTHOR]

Ion imprinted CdS/HTNW photocatalytic membrane (IM-Cd/HT membrane) was prepared by assembling the oxidation type H 2 Ti n O 2n+1 ·xH 2 O nanowires (HTNW) and the reduction type ion imprinted CdS (IM-CdS) for the removal of Cr6+ and tetracycline. Due to the imprinted cavities, Cr6+ was preferentially adsorbed and trapped at specific reaction sites for reduction reactions under the interference of other ions, and the selective reduction coefficients reached 80.01-fold and 91.92-fold. More intriguingly, Cr6+ and tetracycline reacted on the IM-Cd/HT membrane in a heterotopic manner, Cr6+ migrated to IM-CdS for selective reduction, while tetracycline migrated to HTNW for synergistic oxidation, and there was no interference between the two reactions, thereby IM-Cd/HT membrane exhibited a good synergistic balanced removal effect for Cr6+ and tetracycline. Besides, the Cr6+ flux of IM-Cd/HT membrane reached about 2952 L m−2 h−1 bar−1, and the rejection rate of Cr6+ was 62.02%. This study provides a reference for the design of functional self-cleaning membrane with good synergistic photocatalytic ability. [Display omitted] • A novel heterotopic reaction IM-Cd/HT membrane is synthesized. • Selective reduction of Cr6+ and oxidation of TC at different reaction sites are achieved. • The heterotopic reaction strategy reduces the interference between different pollutants. • The ability of synergistic photocatalytic removal of Cr6+ and TC is enhanced. • IM-Cd/HT membrane has good stability, self-cleaning, flux and retention effect. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel heterojunction CdS–WO3 photocatalyst is prepared via hydrothermal method. [•] The combination of 30%-CdS–70%-WO3 results in a highly active photocatalyst for the degradation of Ciprofloxacin. [•] Holes were the main active species of the CIP degradation. [•] The CdS–WO3 photocatalyst has good stability. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new composite surface molecular imprinting photocatalyst was synthesized. [•] The MIP photocatalyst played the highest photocatalytic activity. [•] The effects of various factors on the degradation behavior were investigated. [•] The first-kinetic and second-kinetic of photocatalytic degradation were studied. [ABSTRACT FROM AUTHOR]

Oxygen vacancy and template cavity riched TB-TiO 2 @MFA prepared by one-step pollutant template method exhibits excellent selective degradation ability to CIP under visible light irradiation. [Display omitted] • TB-TiO 2 @MFA is obtained by one-step pollutant template method. • One-step pollutant template method endows samples with oxygen vacancy and template cavity. • Template cavities are used to enhance the selectivity and the specific surface area. • Oxygen vacancies are formed to improve the visible light catalytic performance. • TB-TiO 2 @MFA has excellent selective degradation ability to CIP. Currently, the lack of visible light response, small specific surface area, and non-selectivity limit the development of TiO 2. In this paper, the black TiO 2 @MFA with template cavity (TB-TiO 2 @MFA) was synthesized by one-step pollutant template method. The one-step pollutant template method not only endowed the sample with a large number of oxygen vacancies, but also simultaneously endowed the sample with a wealth of template cavities. The existence of oxygen vacancy improved the electron transfer efficiency and visible light absorption ability, the existence of template cavity improved the contact of TB-TiO 2 @MFA with ciprofloxacin (Template pollutant). Hence the existence of oxygen vacancy and template cavity together led to the improvement of the photocatalytic performance of TB-TiO 2 @MFA. The degradation rate of TB-TiO 2 @MFA to ciprofloxacin is 11.5 times that of TiO 2. More importantly, the template cavity endowed the sample with excellent selective degradation ability, the selectivity coefficient of TB-TiO 2 @MFA to TiO 2 @MFA was 2.44, and the selectivity coefficient of TB-TiO 2 to TiO 2 was 2.76. This work had certain reference significance for designing specific functional photocatalytic materials. [ABSTRACT FROM AUTHOR]

Recyclable flower-like MoS 2 @Fe 3 O 4 @Cu 2 O like-Z-scheme heterojunction based on magnetic assembly method exhibits efficient visible light catalytic ability. [Display omitted] • Flower-like MoS 2 @Fe 3 O 4 @Cu 2 O is obtained by magnetic self-assembly method. • The assembly of 2D into 3D structure is promoted by the mutual attraction between Fe 3 O 4. • The growth of Cu 2 O nanoparticles is limited by the flower-like structure. • Like-Z-scheme heterojunction is formed to improve the photocatalytic performance. In this work, the recyclable flower-like MoS 2 @Fe 3 O 4 @Cu 2 O like-Z-scheme heterojunction (MFC) was synthesized by magnetic assembly method, which not only exhibited excellent magnetic separation performance, but also possessed efficient visible light catalytic ability. Interestingly, the existence of Fe 3 O 4 not only endowed the material good recyclability, but also promoted the formation of like-Z-scheme heterojunction and improved the charge separation efficiency. More importantly, the assembly of MoS 2 (M) nanosheets into the flower-like structure was promoted by the mutual magnetic attraction between Fe 3 O 4 nanoparticles, and the growth of Cu 2 O nanoparticles was limited by the flower-like structure. Based on the improvement of charge separation efficiency and the formation of like-Z-scheme heterojunction, the photocatalytic efficiency of MFC was 3.5, 1.75 and 2.5 times that of MoS 2 (M), MoS 2 @Fe 3 O 4 (MF) and MoS 2 @Cu 2 O (MC), respectively. This work provided a new method for the assembly and design of highly active composite materials. [ABSTRACT FROM AUTHOR]

The magnetic controllable imprinted photocatalyst fabricated by photoinduced surface imprinted technique exhibits good controllable and selective degradation ability. • MCIP with good recyclability is obtained by photoinduced surface imprinted technique. • MCIP has good controllable degradation ability due to the existence of PNIPAM. • MCIP exhibits good selectivity to ciprofloxacin due to the existence of imprinted cavity. In this article, magnetic controllable imprinted photocatalyst (MCIP) was fabricated by photoinduced surface imprinted technique. The degradation rate of ciprofloxacin by MCIP at 20 °C (70.85 %) was higher than that at 40 °C (55.06 %), compared with other materials, MCIP exhibited good controllable degradation ability due to the state of expansion or contraction at different temperatures. Moreover, when the temperature was 20 °C (or 40 °C), the coefficient of selectivity of MCIP to magnetic controllable non-imprinted photocatalyst (MCNIP) was 2.40 (or 2.80) in the single solution, and the coefficient of competitiveness of MCIP to MCNIP was 1.40 (or 1.37) in the mixed solution, above results indicated that MCIP exhibited good selective degradation ability. This work made the functional application of photocatalyst have a better prospect. [ABSTRACT FROM AUTHOR]

Fabricating 2D CN and COF based all organic van der Waals heterojunction catalyst for efficient transformation of CO 2 to hydrocarbon fuels. • 2D CN and COF based all organic heterojunction catalyst 2D CN-COF was successfully prepared. • The heterojunction arose from the interface van der Waals interaction between 2D CN and COF-TD. • The photoelectrical properties of 2D CN-COF was significantly enhanced due to the formation of heterojunction. • The CO evolution rate over 2D CN-COF is 9.2 times and 3.3 times higher than that of 2D CN and COF-TD, respectively. • The reaction was performed in the absence of any solvent and sacrificial agent. Two dimensional carbon nitride (2D CN) has attracted extensive attention due to its potential application in the field of photocatalysis. However, the poor electron-hole separation efficiency and low charge carrier migration speed confine the photocatalytic performance of 2D CN. In this work all organic van der Waals heterojunction (vdWH) catalyst (2D CN-COF) was prepared from 2D CN and triazine-based covalent organic framework (COF-TD) to efficiently enhance the catalytic activity of 2D CN. Characterization and simulation results verified the successful preparation of the catalyst. The heterojunction was originated from the intense interface van der Waals force interaction between the molecules of 2D CN and COF-TD. Furthermore, the intense π-π interaction between 2D CN and COF-TD led to the morphology transformation of COF-TD from sphere of isolated sample to elliptic sheet in 2D CN-COF. The intimate interface contact of vdWH has led to reduce bandgap, which remarkably enlarged the visible light responding region of the samples. Meanwhile, the charge carrier recombination was significantly reduced because of the formation of vdWH. The evolution rate of CO over 2D CN-COF was 9.2 times and 3.3 times higher than that of 2D CN and COF-TD, respectively. Moreover, the reaction was performed in the absence of any solvent and sacrificial agent, matching well with the idea of sustainable development. This work not only provides a new and simple strategy to fabricate 2D CN based all organic heterojunction catalyst for efficient photoreduction of CO 2 to CO and CH 4 , but also serves as a reference for other researchers to design organic heterojunction, which is based on 2D CN and COFs. [ABSTRACT FROM AUTHOR]

• Novel 2D/2D ZIS-S/CN VDW photocatalyst with sulfur vacancies is successfully fabricated. • Efficient H 2 evolution is realized over 30ZIS-S/CN VDW heterojunction composite. • The synergy of VDW heterojunction and sulfur vacancies makes superior photocatalytic activity. • Photocatalytic mechanism in ZIS-S/CN VDW is confirmed by experiments and theory calculation. Fabricating 2D/2D heterojunction with vacancy is more favorable to the spatial separation and transfer of charge owing to the matching of unique 2D structure and vacancy engineering, but the regulation and observation of interlayer forces and electronic structure is a challenging task for synthesizing heterojunction photocatalyst and studying the photocatalytic hydrogen evolution mechanism. Herein, an original 2D/2D ZnIn 2 S 4 /g-C 3 N 4 Van der Waals heterojunction with S vacancies (ZIS-S/CN VDW) photocatalyst are firstly engineered. The optimized 30ZIS-S/g-C 3 N 4 has the highest H 2 evolution rate of 6095.1 μmol h−1 g−1, which is primarily attributed to the fact that 2D/2D VDW heterojunction possesses larger contact area and strong electronic interaction to stimulate charge kinetics, and the vacancy engineering can enhance light absorption by regulating the electronic band structure and act as effective active sites for capturing electrons. This work not only enriches 2D/2D heterojunction photocatalytic system based on g-C 3 N 4 , but also provides alternative proposal for engineering 2D/2D heterojunction photocatalyst with satisfactory performance. [ABSTRACT FROM AUTHOR]

• One-step hydrothermal for the synthetization of BiVO 4 -C nanocomposite. • Lignin was controlled the self-assembly process of BiVO 4. • The lignin was carbonized to porous carbon materials. • BiVO 4 -C nanocomposite showed the enhanced photocatalytic activity. Explorations of biomass materials have emerged as a novel strategy to control the synthesis of semiconductor and improve the photocatalytic performance. Here, a lignin-derived porous structure of BiVO 4 -C nanocomposite was prepared via one-step hydrothermal approach. In the preparation process, lignin not only effectively controlled the growth of BiVO 4 but also carbonized to form a porous structure of biochar-based semiconductor photocatalyst. The studies demonstrated that the BiVO 4 -C nanocomposite have enhanced photocatalytic activity due to the departure of electron-hole pairs and charge migration. These insights provided useful insight for the design of efficient biomass-based photocatalyst for environmental protection and green energy. [ABSTRACT FROM AUTHOR]

Synthesis of carbon nitride based catalysts containing donor-acceptor systems for photocatalytic reduction of CO 2 to CO. • Carbon nitride with donor-acceptor (D-A) systems was fabricated by C and O co-doping. • The D-A systems optimize the optical absorption and bandgap structures of carbon nitride. • The spatial separation of charge in D-A systems enhances the charge separation efficiency. • The catalyst displayed efficient CO 2 photoreduction activity and catalytic durability. Photocatalytic reduction of CO 2 to hydrocarbon fuels is an ultimate and utmost strategy to resolve the ever-increasing environmental problems and energy crisis. Our study aimed to develop a specific type of photocatalysts with increasing light utilization efficiency, reducing electron-hole recombination rate and enhancing photocatalytic activity by integrating unique donor-acceptor systems into the polymeric network of graphitic carbon nitride (g-CN). The results of the characterization showed that C and O are successfully integrated into the framework of g-CN. The O-containing and C-containing section of the as-prepared catalysts (OCCNx) play the role of donor and acceptor, respectively. The donor-acceptor systems of OCCN x offer an extra electron transfer transition mode, which dramatically extends the optical absorption range, and narrows down the bandgap of g-CN from 2.74 to 2.03 eV. Also, the donor-acceptor systems significantly improve the delocalized ability of the photoinduced charge carriers, which efficiently prolongs the lifetime of the charge carriers and reduces the electron-hole recombination rate, as all of these are all beneficial for boosting the photocatalytic activity of the catalysts. Experimental results show that OCCN 0.25 displays the best photocatalytic CO 2 reduction performance with a CO production rate of 34.97 μmol g−1 in 4 h, which is 4.3-fold higher than that obtained in the case of bulk g-CN. Moreover, the reaction is performed in water without any co-catalyst and sacrificial agent, which makes it a green and environmentally friendly reaction. Results obtained from DFT simulation agree well with the empirical results, and a possible reaction mechanism is suggested based on these calculations. [ABSTRACT FROM AUTHOR]

• CdS/Ti3+/N-TiO 2 composite is first fabricated for photocatalytic hydrogen evolution. • CdS/Ti3+/N-TiO 2 displays enhanced light absorption due to the N-doping and Ti3+/O V. • The heterojunction structure of CdS/Ti3+/N-TiO 2 promotes the charge separation. • CdS/Ti3+/N-TiO 2 shows highly efficient H 2 evolution under visible light irradiation. In the practical photocatalytic hydrogen evolution process, the light absorption, charge carrier separation and optimizing the activation ability of reactive molecules are the pivotal factors that restrict photocatalytic performance. Hence, we rationally engineer novel CdS/Ti3+/N-TiO 2 (TNTC) composite photocatalyst via integrating the evaporation induced self-assembly (EISA) and in-situ hydrothermal method. In the TNTC system, Ti3+/O V and doped N respectively locate at below the conduction band (CB) and above the valence band (VB) of TiO 2 to shorten the band gap from two inverse directions, thereby improving light utilization efficiency. The type II heterojunction TNTC with interfacial coupling effect can foster the spatial charge separation and the Ti3+ can form hydrogenation layer to reduce the activation barrier of H 2 , which all can improve H 2 evolution capacity. Integrating with the above advantageous qualities, the 10%CdS/Ti3+/N-TiO 2 (TNTC10) has the best photocatalytic H 2 evolution activity (1118.5 μmol), which is about 15 and 40 times higher than that of CdS (71.6 μmol) and Ti3+/N-TiO 2 (TNT, 27.7 μmol), respectively. Furthermore, we also test the photocatalytic activity of 10%CdS/N-TiO 2 (NTC10) to facilitate comparison with TNTC10. Expectedly, the photocatalytic activity of TNTC10 is 6 times higher than that of NTC10 (178.3 μmol), uncovering that the Ti3+ hydrogenated layer plays a pivotal role in boosting the efficiency of H 2 evolution. It is hoped that this work will provide a new cognitive perspective and understanding for building new-fashioned hydrogen evolution photocatalysts. [ABSTRACT FROM AUTHOR]

• The g-C 3 N 4 /7Ag/m-CeO 2 composite photocatalyst was successfully synthesized. • The introduction of g-C 3 N 4 nanosheets alleviated the photocorrosion of Ag. • The g-C 3 N 4 /7Ag/m-CeO 2 exhibits higher activity for CO 2 photoconversion. In this work, the ordered mesoporous CeO 2 (m-CeO 2) was successfully fabricated via the nanocasting pathway, through using SBA-15 as a hard template. Besides, g-C 3 N 4 /Ag/m-CeO 2 composite was successfully constructed by calcination method. Meanwhile, the obtained samples were investigated by series of test techniques. The XRD, SEM and TEM results show that the m-CeO 2 and Ag/m-CeO 2 with the ordered mesoporous trait. Besides, the EPR, Raman and XPS results suggest that the oxygen vacancies (O v) and Ce3+ and Ce4+ are in g-C 3 N 4 /Ag/m-CeO 2. In addition, the ordered mesostructure is favorable for the CO 2 molecular movement and adsorption/desorption reaction. The g-C 3 N 4 nanosheets, a promising material possessing suitable conductor band, large specific area, non-toxicity, and outstanding chemical stability, is a candidate semiconductor for CO 2 conversion. The introduction of g-C 3 N 4 nanosheets to Ag/m-CeO 2 overcomes the photocorrosion of Ag nanoparticles and Ag facilitate the transfer of photogenerated electrons. The photocatalytic activity results show that when the loading of Ag is 7 wt%, the g-C 3 N 4 /7Ag/m-CeO 2 composite exhibits the superiority activity for CO 2 photoconversion to CO (13.94 μmol/g) and CH 4 (7.39 μmol/g) under UV-irradiation in 10 h. [ABSTRACT FROM AUTHOR]

Exploring semiconductor-based photocatalysis toward reaching solar energy conversion was an ideal strategy. Here, Ni(OH) 2 was used an effective co-catalyst instead of noble metal to construct a novel two dimensional 2D/2D Ni(OH) 2 /Bi 4 Ti 3 O 12 composites with interfacial interaction between Ni(OH) 2 and Bi 4 Ti 3 O 12. The layer Ni(OH) 2 /Bi 4 Ti 3 O 12 composites showed higher photocatalytic activity as compared to pure samples, which was attributed to the interfacial interaction to promote the electron-holes separation. Thus, this work provided a novel insight into design 2D/2D nanocomposites and proved Ni(OH) 2 could excellently act as the effective co-catalyst instead of noble metal to enhance photocatalytic activity. • An efficient co-catalyst of Ni(OH) 2 instead of noble metal to modify Bi 4 Ti 3 O 12. • A new 2D/2D layer-like Ni(OH) 2 /Bi 4 Ti 3 O 12 composites were constructed. • The interfacial interaction and 2D coupling interfaces, promoting the electron-holes separation. [ABSTRACT FROM AUTHOR]

This work focused on the utilization of biological extract for the preparation of lignin-based carbon composites materials and used in the field of photocatalysis. A straightforward one-step carbonization way has been developed to prepare vanadium-doped lignin-based carbon/Bi 2 O 3 composites photocatalyst by using sodium lignosulfonate as the carbon source and catalyst. The application of lignin as the carbon source to form photocatalyst support tends to control the uniform distribution. At the same time, sodium lignosulfonate as the catalyst could break down the BiVO 4 during carbonization process. A series of characterizations demonstrated the BiVO 4 was transformed into Bi 2 O 3 and vanadium-doped lignin-based carbon. The possible synthesis process was proposed. Moreover, the novel V-doped carbon/Bi 2 O 3 composites photocatalyst displayed higher photocatalytic activity than bare BiVO 4. A possible photocatalytic mechanism was also discussed. This work provided new insight into the lignin-based carbon materials. • One-step carbonization for preparing novel V-doped lignin-based carbon/Bi 2 O 3 composites. • The biological extract of sodium lignosulfonate lignin both as the carbon source and catalyst to form carbon supporter and decomposition of BiVO 4. • The V played as the trapping centers in the lignin-based carbon for effectively separation of electron-hole pairs. [ABSTRACT FROM AUTHOR]

Reinforcing separation of charge carriers and increasing electron density played a leading role in improving photocatalytic performance. In this work, incorporating homojunction and heterojunction in quantum dots (QDs) self-modified Bi 2 MoO 6 /Bi 4 Ti 3 O 12 (BMO(Q)/BTO) composites had been rationally designed, and a newfangled photocatalyst had been acquired which could realize the fine manipulation of charge carriers flow direction. Among multitudinous samples, the 15-BMO(Q)/BTO composite exhibited the optimal photocatalytic properties and pervasive applicability for removing the various pollutants (dye, mercaptan and heavy metal) under visible light. We utilized the three-dimensional excitation-emission matrix fluorescence spectroscopy (3D EEMs) to fully grasp the degradation behaviors of RhB. The encouraging increase in photocatalytic activity was mainly attributed to the unified transfer of electrons generated by BMO QDs and BTO to the conduction band of BMO, which effectively increased charge carrier lifetime and improved the conduction band electron density. Furthermore, the photocatalytic degradation mechanism over 15-BMO(Q)/BTO composite was systematically investigated by the calculation, trapping experimental and ESR. The ·OH undertook the active constituent in the process of degradation pollutants. The result suggested that the construction of homojunction/heterojunction photocatalysts to enhance electrons density was a reliable design idea. Unlabelled Image • The QDs self-modified Bi 2 MoO 6 /Bi 4 Ti 3 O 12 photocatalyst was successfully prepared. • The 15-BMO(Q)/BTO possessed the highest photocatalytic performance for degrading pollutants. • Improved photocatalytic activity was due to effective control of electronic unidirectional flow and carrier separation. • Photo-degradation pollutants mechanism of the 15-BMO(Q)/BTO composite was discussed and elucidated in detail. [ABSTRACT FROM AUTHOR]