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The Ag 2 O/Ag 2 CO 3 /multi-walled carbon nanotube (MWNTs) composite photocatalysts were prepared by calcination of the obtained precipitate. The structures and morphology of as-prepared composite photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS). The Ag 2 O/Ag 2 CO 3 /MWNTs composite photocatalysts exhibit higher degradation rate of ciprofloxacin (CIP) than the pure Ag 2 CO 3 , Ag 2 O/Ag 2 CO 3 and Ag 2 CO 3 /MWNTs under visible light irradiation. The amount of loaded Ag 2 CO 3 onto MWNTs and calcined time for Ag 2 CO 3 /MWNTs were systematically investigated, and the optimal amount of loaded Ag 2 CO 3 and calcined time of Ag 2 CO 3 /MWNTs are 150 wt% and 10 min, respectively. The highest photocatalytic degradation rate of CIP could reach 76% under optimal conditions. The active species trapping experiments were also analyzed, the results show that the holes are main contributor for the degradation processes of CIP, furthermore the electrons, O 2 − and OH are also crucially influenced the photocatalytic degradation processes of CIP. The possible photocatalytic processes of CIP with Ag 2 O/Ag 2 CO 3 /MWNTs composite photocatalyst are also proposed. [ABSTRACT FROM AUTHOR]

Ag/Ag 3 PO 4 /active carbon (AC) composite photocatalysts were successfully synthesized using the simple deposition and photoinduced methods. The structures, morphology and photocatalytic properties of as-prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS). The Ag/Ag 3 PO 4 /AC composite photocatalysts exhibited a conspicuously improved photocatalytic performance for tetracycline (TC) degradation. The optimal conditions of loaded dosage and photoinduced time were investigated, and the results showed that the photoinduced time played an important role in prepared processes, and also that for the loaded dosage of Ag 3 PO 4 . The DRS analysis showed that the composite photocatalysts exhibited strong absorption ability in the visible light range. The radicals trap experiments demonstrated that there were multiple active species during the degrading process of TC. The possible mechanism of improved photocatalytic activity of Ag–Ag 3 PO 4 /AC composite was also proposed. [ABSTRACT FROM AUTHOR]

In this work, thermo-responsive PNIPAM@AgBr/CSs composite photocatalysts were successfully fabricated by grafting method. The thermo-responsive composite photocatalysts were further characterized by SEM, EDS, XRD, FT-IR, DRS and PL, the results demonstrated that the surface of CSs was successfully loaded with AgBr and further grafted with PNIPAM, and the grafted PNIPAM not only obtained the thermo-responsive performance, but also synergistically enhanced visible light photocatalytic activity toward degradation of tetracycline (TC) antibiotics. The influenced factors of photocatalytic degradation were also investigated, the results showed that the dosage of PNIPAM and the reacted temperature were obviously affected the degradation rate of TC. Lastly, the photocatalytic degradation mechanism of as-obtained thermo-sensitive photocatalyst was also discussed in detail. This work might offer a way to obtain the intelligently composite materials for switchable photocatalytic processes. [ABSTRACT FROM AUTHOR]

Wide-light absorption performance and efficient carrier separation ability are the necessary conditions for excellent photocatalytic materials. In this research, g-C 3 N 4 QDs (CN QDs) and Au nano-particles (NPs) co-modified CeO 2 /Fe 3 O 4 micro-flowers (MFs) photocatalyst (CACeF) has been prepared. CO 2 photoreduction experiments showed that the composite had obviously enhanced photoreduction activity and photocatalytic stability. The yields of CO and CH 4 over it as catalyst in 4 h is about 5 and 8 times greater than that of pure CeO 2. Photoelectrochemical tests showed that the heterojunction between CN QDs and Au NPs can greatly improve the carrier separation ability and the light-utilization efficiency of photocatalysts. Besides, the excellent electronic transmission performance of Au NPs provided a specific channel for the electron transmission, and the strong local surface plasmon resonance (LSPR) of Au NPs resulted in a lot of hot-electrons can directly take part in the CO 2 photoreduction. The synergistic effect between CN QDs and Au NPs can further enhance the photocatalytic activity of the photocatalyst. Fe 3 O 4 QDs can ensure the effective recovery and reuse of the composite without affecting the photocatalytic performance of composite. Finally, a potential photoreduction mechanism of CN QDs and Au NPs co-modified CeO 2 /Fe 3 O 4 MFs photocatalyst were discussed in total. [Display omitted] • g-C3N4 QDs/Au NPs/CeO2/Fe3O4 has been prepared for the CO2 photoreduction. • Light-absorption performance of photocatalyst has been greatly enhanced. • Au efficiently speeds up the electrons' generation efficiency in semiconductors. • Synergistic effect of CN QDs/Au NPs enhanced the photoreduction performance. • Fe3O4 QDs can ensure the recovery without affecting the photocatalytic performance. [ABSTRACT FROM AUTHOR]

Achieving the intelligent controllability of the photocatalyst to the surrounding environment is a very meaningful work. Here, the polyacrylic acid (PAA) modified Ag/AgCl-40/CN composite was constructed to achieve an intelligent response of pH value. PAA exhibits hydrophilic properties at high pH value, increasing the adsorption capacity to tetracycline (TC) molecules. The morphology of PAA from contracted state to diastolic state, releasing the Ag/AgCl-40/CN catalyst. In addition, PAA modified Ag/AgCl-40/CN can prevent the loss of AgCl. The g-C 3 N 4 nanosheets (CN) as a carrier enhance the dispersibility of the AgCl particles. The LSPR effects of Ag nanoparticles produce more electrons acting on photocatalytic degradation. On the results of experiment, the degradation of TC by PAA@Ag/AgCl-40/CN shows an excellent degradation activity when the high pH value. Photoluminescence spectroscopy and photocurrent demonstrate that carrier separation efficiency of PAA@Ag/AgCl-40/CN is higher than CN and Ag/AgCl-40/CN. The detection of the main active substances •O 2 − and h+, revealing a reasonable mechanism for the PAA@Ag/AgCl-40/CN hybrid system. This work provides a procedure to obtain smart materials that can switch photocatalytic processes. [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]

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]

High selectivity and fast charge separation are two important factors for photocatalytic wastewater treatment. Herein, we prepared a molecular imprinted Ag/Ag 3 VO 4 /g-C 3 N 4 photocatalyst (MIP) that exhibited great specific recognition ability along with excellent photocatalytic activity. The ultrathin g-C 3 N 4 nanosheets with high surface are used to prepare. The Z-scheme Ag 3 VO 4 /g-C 3 N 4 heterostructure and the surface plasmon resonance of the photoreduced Ag0 together contributed to the improvement of the separation efficiency of photogenerated electrons and holes. In addition, MIP provides the specific recognition ability to preferentially adsorb the target pollutant. The selectivity of photocatalysis was evaluated by the degradation of oxytetracycline and tetracycline solutions. Photoluminescence and transient photocurrent measurements further prove the improved charge separation efficiency of MIP. A plausible photocatalytic reaction mechanism is proposed based on electron spin resonance measurement and the active species trapping experiments, where indicates that the main active species of this photocatalytic process are O 2 − and h+. This research provides an effective strategy for the simultaneous enhancement of selectivity and activity via molecular imprinting. [ABSTRACT FROM AUTHOR]

The interfacial regulation strategy between semiconductors can effectively promote the separation efficiency of photogenerated carriers and enhance photocatalytic activity under the synergistic effect. Herein, AgInS 2 QDs-MoS 2 /GO (AIS-MS/GO) composites were prepared by interfacial coupling of AgInS 2 QDs (AIS), hierarchical MoS 2 and ultrathin GO. Ultrathin GO successfully solved the agglomeration problem of AIS and hierarchical MoS 2. Moreover, the photogenerated carriers were effectively separated and transferred under the synergistic effect of the AIS-MS heterojunction and ultrathin GO, thus promoting tetracycline (TC) degradation and CO 2 reduction performance. The degradation rate of tetracycline (TC) reached 96.5 %, and the yields of CO and CH 4 in the CO 2 reduction products reached 52.6 and 28.5 μmol g–1, respectively, when using the optimized photocatalyst. In-situ FTIR analysis indicated that TC is gradually degraded by small molecules on the composite surface, and has excellent dissociation ability of water molecules during the CO 2 reduction process. This work provides a new vision for the rational design of heterojunction-based photocatalysts using the interfacial regulation strategy for enhancing interfacial charge separation and photocatalytic performance. [Display omitted] • AIS-MS/GO composites were prepared via the interfacial regulation strategy. • The photogenerated carriers were effectively separated and transferred under synergistic and interfacial effects. • The aggregation problem of AIS and hierarchical MoS 2 was effectively solved. • AIS-MS/GO composites achieve a 96.5 % TC degradation rate and 35.1 % selectivity for CH 4. [ABSTRACT FROM AUTHOR]

Graphical abstract Schematic illustration of the formation of CQDs/ZnO@HNTs in the whole synthetic process. Highlights • We have experimentally demonstrated the carbon incorporated ZnO via coupling CQDs. A notable transformation of burger-like CQD s /ZnO morphology was observed and the HNTs have been introduced to improve the dispersity of hybrid photocatalysts. • From efficiently modulation of band structure of CQD s -based materials, the as-prepared CQD s /ZnO@HNTs display a remarkable optical excitation in photogenerated reactive oxygen species (ROS). • This work provides an efficient and novel strategy for element incorporated with introduced inorganic quantum dots owing to the quantum size effect. • It also developed a new sight of CQD s participated phase tuning for semiconductors, offering a beneficial route for expanding the application of VLD photodegradation based on band-tuning semiconductors and other low-dimension materials. Abstract Environmentally friendly photodegradation of refractory pollutants utilizing semiconductor photocatalysis evolution exhibits satisfactory efficiency and low energy consumption, but some of its unbefitting band position largely limits practical applications. The controllable band structure tuning via coupling low-dimensional materials with enormous potential in semiconductor photocatalysis, notably attractive carbon quantum dots (CQDs) induced for a better utilization of low-energy photoexcitation of promising inherent optical properties and photocatalytic performance on organic pollutant degradation. Here, a CQDs modified ZnO hybrid materials was synthesized and the CQDs preluded carbon-incorporated burger-like ZnO nanoparticles clusters were presented thus demonstrated a specific doping-effect. The dispersity improved by loading halloysite nanotube (HNTs) for efficiently photocatalytic activity enhancement. Furthermore, the band structure, excitation and photocatalytic reactive oxygen species (ROS) generation were detected to reveal the photochemical properties and plausible mechanism of CQDs hybrid nanomaterials system. It is observed that the superoxide radical (O 2 −), and singlet oxygen(1O 2) are the principal ROS agents under UV–vis excitations. This work not only displays a CQDs modified system of expanding photo-response range to visible light but also throws a way for quantum elemental incorporated on the influence of band-tuning for semiconductor- dominated photocatalysts. [ABSTRACT FROM AUTHOR]

A multiple transmission channels, heterojunction and 3D PCN/AgBr/rGO photocatalyst was successfully synthetized by introducing the reduced graphene oxide (rGO) covering AgBr onto the surface of 3D porous g-C 3 N 4 (PCN). In PCN/AgBr/rGO, PCN as a semiconductor photocatalyst provides the 3D framework, the heterojunction was formed with AgBr particles and PCN, rGO promotes the electron transfer simultaneously and introduces a multiple transmission channels system to increase the active species. Thanks to the heterojunction formed between PCN and AgBr, resulting rapid separation of photo-generated e − /h + at interface. The 3D PCN/AgBr/rGO nanocomposite exhibits excellent photocatalytic efficiencies for tetracycline (TC) up to 78.4% within 90 min and 2,4-dichlorophenol (2,4-DCP) up to 68.2% within 6 h. The photocatalytic rate of PCN/AgBr/rGO was much higher than 3D PCN (21%), AgBr particles (31%) and most of g-C 3 N 4 -based photocatalysts in TC degradation. Moreover, the PCN/AgBr/rGO shows high photocatalytic stability due to the significantly photocatalytic stability after four photo-degradation cycles. This study highlights the potential application of PCN/AgBr/rGO highly efficient waste water purification. [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]

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]

The 3D hierarchical structure of CdS/Ni-MOF inhibits the agglomeration of CdS, improve light harvesting, increase active surface area, reaction sites, promote charge transfer and separation, which greatly improves the efficiency of CO 2 conversion. However, when the CdS is overloaded and its hierarchical structure is destroyed, the heterostructure plays a major role in improving the performance. Based on the above results, we propose the preliminary mechanism of 20%-CdS/Ni-MOF photocatalytic reduction of CO 2. Firstly, under UV–Vis illumination, Ni-MOF and CdS are excited to produce electrons (e−) and holes (h+). Then, because of the tight interface contact, the e- excited by Ni-MOF could be transferred to CdS with more positive CB, and CdS as the active site could reduce CO 2 to CO more effectively. At the same time, the h+ in the VB of Ni-MOF and CdS participate in the oxidation reaction to produce O 2 and H 2 O 2 , which achieving the elimination of holes. Such charge separation and transfer of the electron-hole pairs facilitate enhanced photocatalytic activity. [Display omitted] • The 3D hierarchical heterostructure was synthesized by a simple strategy. • 20%-CdS/Ni-MOF showed excellent performance in the vapor–solid reaction system. • The hierarchical structure and heterostructure of CdS/Ni-MOF play a synergistic role. Fabricating the hierarchical heterostructure is efficient way for enhancing CO 2 conversion of semiconductor photocatalysts. Herein, a simple strategy has been employed to prepare several 3D hierarchical CdS/Ni-MOF heterostructure photocatalysts, and the selective photoreduction of CO 2 to CO under simulated sunlight in the gas–solid phase reactor. Among the prepared photocatalysts, 20%-CdS/Ni-MOF shows the best CO yield, which was 16 times and 7 times that of Ni-MOF and CdS, respectively. By controlling the morphology of the catalyst, we found that the significant improvement in photocatalytic activity can be ascribed to the synergistic effect of heterostructure in CdS/Ni-MOF and its unique hierarchical structure, which can improve the efficiency of charge transmission and provides abundant active sites, etc. Finally, the preliminary photocatalytic mechanism was discussed by in situ FTIR and liquid ultraviolet spectrophotometer. [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]

Energy band location and charge separation mechanism of SnS 2 /Au/g-C 3 N 4 system during photoreduction under sunlight irradiation. • The catalyst is prepared by facile thermal treatment and chemical deposition method. • The SnS 2 /Au/g-C 3 N 4 composites show a superior optical adsorption under UV–vis light. • The Au nanoparticle and the Z-type scheme jointly improve the separation of carrier. • The SnS 2 /3ml-Au/g-C 3 N 4 displays the best photoreduction activity and durability. The use of semiconductor photocatalytic reduction technology has higher efficiency and lower energy consumption for CO 2 reduction, but its existence of some mismatched energy band positions and relatively slow charge-hole separation greatly limits its practical application. In this paper, a SnS 2 /Au/g-C 3 N 4 embedded structure model with carbon and nitrogen hybridization is proposed to gain an in-depth understanding of the role of hybridization and precious metal modification in photocatalysis. Carriers were investigated from the perspective of kinetics through photocurrent, LSV curve, and FL spectroscopy. After modification of Au nanoparticles, the photo-excited electrons showed a slower decay process, indicating that the separation of carriers was enhanced, which was further confirmed by impedance and PL spectroscopy. SEM, AFM and TEM analysis confirmed that the 2D face-to-face SnS 2 /Au/g-C 3 N 4 embedded structure was successfully prepared and the Au nanoparticles were evenly distributed. Au nanoparticles not only act as a bridge for electron transport in 2D semiconductor materials to accelerate electron transport, but generate more excited electrons by themselves under the radiation of sunlight, which effectively improves the separation efficiency of electron-hole pairs and enhances the photocatalyst activity. DFT calculations show that the Z-type mechanism and the intercalated energy level of the SnS 2 /Au/g-C 3 N 4 embedded structure expand the light absorption and improve the carrier separation efficiency. As expected, the photocatalyst activity with CO and CH 4 the evolution rate of up 93.81 µmol·g−1·h−1 and 74.98 µmol·g−1·h−1 under visible light irradiation, respectively, while the photocatalytic activity is negligible loss after 30 h photoreduction. This work reveals the role of embedded structure and precious metal modification in the separation and transmission of electron-hole, opening up new perspective for achieving high-efficiency solar CO 2 reduction performance. [ABSTRACT FROM AUTHOR]

Pt@CeO 2 /3DCN heterojunction are prepared by calcination method and photoreduction technology. The enhanced photoreduction of CO 2 performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO 2 for CO 2 activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO 2 /3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity. • The Pt@CeO 2 /3DCN photocatalyst was successfully synthesized. • Pt@45CeO 2 /3DCN exhibit best ability of CO 2 photoreduction under UV light. • The synergy of CeO 2 and 3DCN improves the photocatalytic performance. The conversion of CO 2 into high value-added carbon-based compounds through photocatalytic reduction technology is considered as one of the more promising strategies to solve the greenhouse effect. And construction of heterojunction photocatalysts can promote the separation of photoelectron-hole pairs, so as to achieve higher activity of photocatalytic CO 2 reduction. Hence, Pt@CeO 2 /3DCN heterojunction are prepared by calcination method and photoreduction technology. The photocatalytic results revealed that Pt@CeO 2 /3DCN show better photocatalytic activity for reducing CO 2 into CO and CH 4 , compared with 3DCN. Especially, Pt@45CeO 2 /3DCN shows the maximum photocatalytic activity of 4.69 and 3.03 μmol·h−1·g−1 for CO and CH 4 under UV light irradiation, respectively, and the reduction activity did not decrease significantly after five cycles. The enhanced photoreduction of CO 2 performance can be ascribed to the synergistic effects of the oxygen vacancies in CeO 2 for CO 2 activation and heterojunction for electron separation. Besides, Pt nanoparticles (NPs) on CeO 2 /3DCN can further promote the transfer of electrons, resulting in higher photocatalytic activity. [ABSTRACT FROM AUTHOR]