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Highly efficient cooperative furfuryl alcohol conversion and H 2 evolution in one photoredox cycle over 1D/2D Mn x Cd 1-x S/Ti 3 C 2 MXene Schottky junction. [Display omitted] • A 1D/2D Mn x Cd 1-x S/Ti 3 C 2 MXene photocatalyst is synthesized. • Furfural synthesis coupled with H 2 production is conducted in one photoredox cycle. • Schottky junction structure facilitates the separation and transfer of photoinduced carriers. • A tentative mechanism for cooperative furfuryl alcohol conversion and H 2 evolution is proposed. Selective and efficient photocatalytic transformation of biomass-derived platform molecules to high-value-added fuels or chemicals is a great challenge for green chemistry, especially utilizing visible light energy and earth-abundant catalytic materials. In this work, we report a 1D/2D Mn x Cd 1-x S/Ti 3 C 2 (MCSTC-X) Schottky junction structure to achieve efficient photocharge separation/transfer via in-situ interfacial self-assembly strategy. Under visible light illumination, the optimized MCSTC-7.5 catalyst enables the selective conversion of furfuryl alcohol into furfural with a production rate of 764.3 μmol·g−1·h−1, accompanied by water splitting into H 2 with a generation rate of 756.5 μmol·g−1·h−1. Benefiting from the internal electric field in the Schottky junction structure, the efficient separation and transfer of photoinduced charge carriers are realized in one photoredox cycle. Moreover, a plausible reaction mechanism for the photocatalytic selective valorization of furfuryl alcohol to furfural and H 2 evolution is proposed. Hopefully, this work would open a new avenue for sustainable and practical production of solar chemicals and fuels by rationally designing 1D/2D Schottky junction. [ABSTRACT FROM AUTHOR]

In-situ constructing Schottky junction via anchoring Ni-P alloy onto defect-rich ZnS nanospheres for highly efficient visible-light-driven photocatalytic H 2 production. • A unique Schottky junction composed of Ni-P alloy and defect-rich ZnS nanospheres (Ni-P/DR-ZnS) was in-situ fabricated. • The Ni-P/DR-ZnS nanocomposites displayed excellent photocatalytic H 2 evolution activity and stability under visible light. • The as-formed Schottky junction accelerated the separation and transfer of photogenerated charge carriers. • The transfer mechanism of photogenerated charge over the Ni-P/DR-ZnS was studied in detail. The development of efficient and stable photocatalysts is fundamentally required for sunlight-driven water splitting. Herein, Ni-P alloy is controllably anchored onto the surface of defect-rich ZnS (DR-ZnS) nanospheres through in-situ photodeposition strategy. The optimized Ni-P/DR-ZnS nanocomposite displays superior visible-light photocatalytic H 2 production rate (69.92 μmol h−1), which is about 29 times and 3.6 times higher than that of the bare DR-ZnS and 1 wt% Pt/DR-ZnS, respectively, and a notable apparent quantum yield of 2.4 % at 420 nm. The existence of rich defects endows the DR-ZnS with visible-light absorption capability. The constructed Schottky junction between the Ni-P alloy and DR-ZnS accelerates the transfer of photogenerated electrons from DR-ZnS to Ni-P, thus boosting the photocatalytic performance. Moreover, the charge transfer process and underlying photocatalytic mechanism are unravelled by multiple in-depth characterizations. This research sheds novel light on rationally fabricating high-efficient and low-cost photocatalysts through integrating defect engineering and Schottky junction design. [ABSTRACT FROM AUTHOR]

• A novel AgIn 5 S 8 /ZnS Z-scheme heterojunction was fabricated for the first time. • The AgIn 5 S 8 /ZnS displayed outstanding photocatalytic H 2 evolution performance. • The Zn defect mediated the transport and separation of charge carriers. • The superior performance was ascribed to the Z-scheme heterojunction. Exploring high-efficiency Z-scheme heterojunction photocatalyst has been regarded as an effective approach for promoting photocatalytic hydrogen production efficiency. In this study, a novel direct Z-scheme heterojunction composed of AgIn 5 S 8 (denoted as AIS) and Zn-defective ZnS (denoted as D-ZnS) was fabricated via two-step hydrothermal method. The AIS/D-ZnS heterojunction exhibited improved visible light harvesting capability, prolonged charge lifetime and promoted charge separation efficiency, thus contributing to the remarkably enhanced photocatalytic activity as well as stability. The photocatalytic H 2 evolution rate of the optimized (0.10:1)AIS/D-ZnS reached 932.76 μmol·h−1 g−1, which was 12 times higher than that of bare D-ZnS (75.13 μmol·h−1 g−1) under visible light irradiation, and an optimal apparent quantum yield of 3.7% was achieved at λ = 420 nm. TEM, XPS, EPR and PL results confirmed the appropriate concentration of Zn defects is conducive to the separation of photogenerated carriers. DMPO-EPR and PL probe experiments for determining O 2 − and OH active radicals further proved that the transfer and separation of electrons and holes followed Z-scheme mechanism. This work not only presents an alternative strategy for the construction of highly efficient Z-scheme heterojunction photocatalysts, but also provides new insights into the role of defects in mediating the separation and migration of charge carriers. [ABSTRACT FROM AUTHOR]