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Dry reforming of methane (DRM), which involves the activation of inert CH bonds and CO bonds, at mild conditions is a tremendous challenge. The sluggish mobility of oxygen during the reaction is known as a key issue causing low activity and poor stability of catalysts by the coke formation. Herein, a novel Cu‐CNN/Pd‐BDCNN photocatalyst that is made up of "Cu‐nanoparticle‐loaded g‐C3N4 nanosheets" and "Pd‐nanoparticle‐loaded boron‐doped nitrogen‐deficient g‐C3N4 nanosheets" is reported. The existing dual‐reaction‐sites benefit the reactive oxygen intermediates participate in the reaction directly without distant migration. The in situ characterizations and density functional theory calculations reveal a newly dual reaction pathway through simultaneous dehydrogenation of methoxy and methyl intermediates, and demonstrate the importance of metal loading, which promote the CO2 and CH4 activation from both aspects of thermodynamics and kinetics. The optimized Cu‐CNN/Pd‐BDCNN photocatalyst displays an excellent syngas formation rate of over 800 µmol g−1 h−1 with H2/CO = 1 and splendid stability in continuous flow reaction under 300 mW cm−2 xenon lamp irradiation at room temperature. The "dual‐site" and "dual‐path" strategy shed light on the design of effective photocatalysts for methane dry reforming. [ABSTRACT FROM AUTHOR]

Successful construction of heterojunction can improve the utilization efficiency of solar light by broadening the absorption range, facilitating charge-carrier separation, promoting carrier transportation and influencing surface-interface reaction. Herein, visible-light-driven AgBr was deposited on the surface of lamellar BiVO4 which was prepared by a facile hydrothermal process to improve charge carrier separation, and subsequent photocatalytic effectiveness. The catalyst with an optimal AgBr/BiVO4 ratio exhibited a superbly enhanced photocatalytic decolorization ability (about 6.85 times higher than that of pure BiVO4) and high stability after four cycles. The unique photocatalytic mechanism of S-scheme carrier migration was investigated on the bases of radical trapping tests and photo/electrochemical characterizations. Results showed that the enhanced migration strategy and intimately interfacial collaboration guaranteed the effective charge carriers separation/transfer, leading to magnificent photocatalytic performance as well as excellent stability. [ABSTRACT FROM AUTHOR]

One of the challenges in developing practical CO2 photoconversion catalysts is the design of materials with a low cost, high activity and good stability. In this paper, excellent photocatalysts based on TiO2, WO3, ZnO, Cu2O and CeO2 metal oxide materials, which are cost-effective, long-lasting, and easy to fabricate, are evaluated. The characteristics of the nanohybrid catalysts depend greatly on their architecture and design. Thus, we focus on outstanding materials that offer effective and practical solutions. Strategies to improve CO2 conversion efficiency are summarized, including heterojunction, ion doping, defects, sensitization and morphology control, which can inspire the future improvement in photochemistry. The capacity of CO2 adsorption is also pivotal, which varies with the morphological and electronic structures. Forms of 0D, 1D, 2D and 3DOM (zero/one/two-dimensional- and three-dimensional-ordered macroporous, respectively) are involved. Particularly, the several advantages of the 3DOM material make it an excellent candidate material for CO2 conversion. Hence, we explain its preparation method. Based on the discussion, new insights and prospects for designing high-efficient metallic oxide photocatalysts to reduce CO2 emissions are presented. [ABSTRACT FROM AUTHOR]

Two‐dimensional Bi2WO6 ultra‐thin nanosheets were controllably synthesized by a cetyltrimethylammonium bromide (CTAB)‐assisted hydrothermal method. The structure, morphology, energy gap, and thickness of the samples were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), (diffuse reflection spectroscopy) DRS, and so on. The photocatalytic activity of the samples was analyzed by the degradation of rhodamine B. The photocatalytic performance of the ultrathin nanosheets was much enhanced nearly 3.5 folds higher than that of Bi2WO6 nanoparticles, which was attributed to the narrow band gap and the open sandwich structure, resulting in the improved light harvesting and the rapid separation and transfer of the photoinduced charge carriers. According to the radical trapping results, the dominant active species involving in the photocatalytic process were determined. [ABSTRACT FROM AUTHOR]

Novel Bi12TiO20/g-C3N4 composite was successfully prepared with Bi12TiO20 nanoparticles embedded within the fluffy crumpled g-C3N4 nanosheets. Bi12TiO20/g-C3N4 composites exhibit superior photoactivity and stability. As compared with g-C3N4 and Bi12TiO20, the photocatalytic efficiency of Bi12TiO20/g-C3N4 is effectively enhanced about 1.8- and 4.9-fold, respectively. Based on the trapping experiment, ·OH and ·O2− radicals are the dominant reactive oxygen species involved in the photocatalytic process. The proposed Z-scheme mechanism of charge transfer markedly promotes the carriers’ migration and separation, leading to the enhanced photocatalytic performance. [ABSTRACT FROM AUTHOR]

With the aid of ethylene glycol and sodium dodecylbenzene sulfonate, the hierarchical Bi 2 WO 6 nanoarchitectures assembled from nanoflakes could be attained by a facile solvothermal method. The synthetic strategy is versatile and environmentally friendly and a plausible growth-assembly process was proposed for the formation of the hierarchical nanostructures. The visible-light-irradiated photocatalytic activity was estimated by the degradation of rhodamine B. Compared with the sample prepared by a solid-state reaction, the visible-light-induced photocatalytic efficiency of the nanostructures was enhanced about 6 times. The photocatalysis tests show that the nanostructures exhibit excellent photocatalytic activity and recycling performance, which were mainly ascribed to the unique hierarchical nanostructures and are expected to offer promising applications in the field of wastewater treatment. [ABSTRACT FROM AUTHOR]

The catalytic efficiency of Ag-modified BaTiO 3 was greatly enhanced (more than 240%) through the synergism among photo-, piezo-catalysis, and the LSPR effect. [Display omitted] • High-efficient catalyst Ag-modified BaTiO 3 was synthesized by photodeposition. • Ag/BaTiO 3 composites exhibit superior catalytic ability and stability. • Enhanced performance (240%) benefits from synergism among photo-, piezo-catalysis, and the LSPR effect. Modifying traditional photocatalysts has always been the focus of scientists' efforts. Using piezoelectric potential to assist photocatalysis can improve catalytic efficiency. The catalytic performance of BaTiO 3 was further enhanced by surface modification of silver nanoparticles deposited by a simple photoreduction method. The synergism among piezo-, photo-catalysis and the LSPR effect greatly enhanced the catalytic efficiency (more than 240%). The involved free radicals generated in the catalytic system and the cycle stability of the catalysts were examined. Based on the experimental results, an enhanced synergistic catalytic mechanism of BaTiO 3 modified with Ag was proposed. The strategy presented here provides ideas for realizing the development of high-efficient catalysts for practical applications. [ABSTRACT FROM AUTHOR]

The g-C 3 N 4 /CeVO 4 composites were successfully synthesized by hybridizing CeVO 4 nanofibers with g-C 3 N 4 nanosheets. The photocatalytic activity of g-C 3 N 4 /CeVO 4 composites was evaluated for the photodegradation of methylene blue under visible light irradiation. Among them, the 50 wt% g-C 3 N 4 /CeVO 4 composites presented the highest photocatalytic activity, about 2 and 3.2 times higher than those of CeVO 4 and g-C 3 N 4 , respectively. The improved catalytic activity was owed to the hybridization, which facilitated the rapid separation of photoinduced carriers and enhanced the visible light harvesting. A possible photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D ordered macro-mesoporpus TiO 2 nanoparticles prepared by dual template method. • Z-scheme charge transferred between TiO 2 and ZnS with Au as intermediation. • Core-shell structured Au@ZnS nanoparticles were precipitated on TiO 2 enhanced absorption of visible light. • The ternary Au@ZnS/3DOMm-TiO 2 -2 catalyst exhibited a high yield (33.2 µmol g-1h−1) and selectivity (91.5 %) for CH 4. • The synergistic effect of slow photon effect and surface plasmon resonance could greatly increase CO 2 reduction efficiency. Hereby, the core–shell structured Au@ZnS nanoparticles were precipitated on three-dimensionally ordered macro-mesoporous TiO 2 (Au@ZnS/3DOMm-TiO 2) by GBMR/P method. The slow photon effect of 3DOM structure leads to increase the light trapping and absorption efficiency. The hierarchical porous structure improves the specific surface area of the carrier, providing a larger internal void for desorption of reaction products and additional activation sites for the CO 2 reduction. In the all-solid Z-scheme system, electrons are transferred along the direction from TiO 2 to Au and finally to the surface of ZnS is realized to participate in the reaction of CO 2 reduction. Under irradiation of visible light, ternary Au@ZnS/3DOMm-TiO 2 -2 catalyst exhibits the highest catalytic activity for CO 2 photoreduction with H 2 O, i.e., the formation rate and selectivity of CH 4 product is 33.2 µmol g-1h−1 and 91.5 %, respectively. The design of Z-scheme heterojunctions on 3D macro-mesoporous oxide surfaces are expected to expand new ideas for the preparation of efficient photocatalysts. [ABSTRACT FROM AUTHOR]

The significant improvement of photocatalytic activity and stability of the composites is attributed to the introduction of holey g-C 3 N 4 NSs, not only promoting the carrier separation and increasing the adsorption of dye molecules, but also protecting Ag 3 PO 4 from dissolution. • Holey g-C 3 N 4 nanosheet wrapped Ag 3 PO 4 composite was prepared at room temperature. • Ag 3 PO 4 /g-C 3 N 4 composites facilitate the migration and separation of electron-hole pairs. • g-C 3 N 4 NSs are crucial to Z-scheme system and protect Ag 3 PO 4 from dissolution. Holey g-C 3 N 4 nanosheet wrapped Ag 3 PO 4 composite was prepared at room temperature by a feasible in situ precipitation. The photoactivity of g-C 3 N 4 /Ag 3 PO 4 was estimated by the RhB decolorization under visible light illumination. The photocatalytic efficiency of the composites with 30 wt% loading is almost enhanced 1.89 folds higher than that of the native orthophosphate. More attractively, the enwrapping can not only promote the separation of photogenerated charges efficiently but also protect Ag 3 PO 4 from dissolution, leading to the significant improvement of the photocatalytic activity and durability. The radical trapping experiment manifests that the predominant active species participated in the organic photodegradation are holes, OH, and O 2 − radicals. On the basis of these results and discussion, a Z-scheme strategy for dye photodegradation against the holey g-C 3 N 4 wrapped Ag 3 PO 4 heterojunction is proposed and further validated by the electrochemical impedance analysis. [ABSTRACT FROM AUTHOR]

A novel ternary graphene oxide (GO)/Ag 3 PO 4 /AgBr composite was synthesized by an in situ growth of Ag 3 PO 4 /AgBr on GO nanosheets. The photocatalytic efficiency of the nanocomposite under visible light irradiation was much enhanced due to the coupling of GO nanosheets and Ag 3 PO 4 /AgBr, which enlarged the absorption region, facilitated the charge transportation, and enhanced the charge collection efficiency. According to the photocatalytic results, the 0.625%GO/Ag 3 PO 4 /AgBr sample shows the highest photocatalytic activity, about 3.6 times higher than that of Ag 3 PO 4 . According to the radical trapping test, the O 2 − and OH radicals, together with h + are the dominant active species in the GO/Ag 3 PO 4 /AgBr photocatalytic process. A possible photocatalytic mechanism for photocatalytic degradation over GO/Ag 3 PO 4 /AgBr was proposed. [ABSTRACT FROM AUTHOR]

Herein, the ternary catalyst of reduced graphene oxide (rGO)-coated Ag/Cu 2 O-octahedron nanocrystals (Ag/Cu 2 O@rGO) was successfully fabricated by method of water bath combining with gas-bubbling-assisted membrane reduction. Supported Ag nanoparticles with low fermi energy can enrich the photogenerated electrons originated from visible light-driven Cu 2 O octahedral nanocrystals. The surface extended π bond of coated rGO nanolayers on Ag/Cu 2 O can further capture photoelectrons and improve adsorption-activation capacities for reactants. Ag n /Cu 2 O@rGO catalysts with ternary rGO-Ag-Cu 2 O heterojunction exhibit excellent performance during selective photocatalytic CO 2 reduction with H 2 O into CH 4. Ag 4 /Cu 2 O@rGO catalyst has the highest formation rate (82.6 μmol g−1 h−1) and selectivity (95.4%) of CH 4 product. Combined with the results of in-situ DRIFT spectra and density functional theory calculations, the photocatalytic mechanism is proposed: the protonation of CO* intermediate is key step for selective photocatalytic CO 2 reduction into CH 4. It provides one novel strategy to development of high-efficient photocatalyst for selective CO 2 conversion into C1 chemicals. [Display omitted] • Novel rGO-coated Ag/Cu 2 O-octahedron photocatalysts were designed and fabricated. • Supported Ag NPs enrich the photoelectrons originated from visible light-driven Cu 2 O. • Surface π bond of coated rGO nanolayers improve adsorption-activation capacities for CO 2. • Ag/Cu 2 O@rGO catalysts exhibit high performances for selective CO 2 reduction into CH 4. • Protonation of CO* intermediate is key step for photocatalytic CO 2 reduction into CH 4. [ABSTRACT FROM AUTHOR]