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Making full use of photogenerated charge carriers by careful design multifunctional photocatalysts to achieving bi-value-added production with high-efficiency is highly desirable and extremely challenge. Herein, a novel 2D/3D ZnIn 2 S 4 @Ni 1 /UiO-66-NH 2 (ZIS@Ni 1 /UN) heterojunction with spatially separated and precise redox sites was designed and fabricated for both photocatalytic H 2 production and benzyl alcohol (BA) valorization. By precise structural regulation and modification of UiO-66 integrated with -NH 2 , ZnIn 2 S 4 (ZIS) and Ni single-atom, the spatial separation of redox sites and directional electron transfer has been achieved. This realizes collaborative and efficient solar energy to chemical energy conversion. The optimal sample 5ZIS@Ni 1 /UN-6 shows high photocatalytic H 2 and benzaldehyde (BAD) production rates of 11.44 mmol∙g−1∙h−1 and 10.02 mmol∙g−1∙h−1 under visible light. This work highlights the importance of rational construction for the engineering of charge behavior in heterogeneous photocatalysts with spatial separation and identifies their crucial role in promoting the photocatalytic redox coupling reactions. [Display omitted] • A novel 2D/3D ZnIn 2 S 4 @Ni 1 /UiO-66-NH 2 heterojunction is successfully design and fabricated. • High production rates of benzaldehyde and H 2 simultaneous is achieved under visible-light. • Precise construction of spatially separated redox-sites and directional electron transfer synergistically boost photocatalytic performance. • The carbon-centered free radical process of selective oxidation of benzylalcohol is confirmed by in-situ EPR. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 0D/2D MoS 3 QDs/C-doped atomic-layer TiO 2 (B) nanosheet composite was fabricated. • The unique nanostructure exhibits remarkable performance for photocatalytic H 2 evolution. • MoS 3 exhibits a superior cocatalyst than MoS 2 and Pt for H 2 evolution and stability. Developing efficient photocatalysts for H 2 generation is of huge interest for sources of long-term sustainable energy. Here, a novel 0D/2D MoS 3 quantum dots (QDs)/C-doped atomically thin TiO 2 (B) nanosheet composite (MoS 3 /TiO 2 (B)-C) was fabricated for H 2 evolution. The simultaneous loading of the highly-efficient cocatalyst MoS 3 and carbon and oxygen vacancy co-doping into an atomically thin TiO 2 (B) nanosheet was achieved by an annealing process. This unique nanostructure of the MoS 3 /TiO 2 (B)-C exhibits remarkable photocatalysis of H 2 in the full spectrum. We obtain a yield of 2.47 mmol·g−1·h−1, 30 times higher than pure TiO 2 (B) nanosheet, and even higher than MoS 2 and Pt loaded TiO 2 (B) nanosheets (2.23 and 2.36 mmol·g−1·h−1, respectively). In-depth characterization shows that notably MoS 3 is a superior cocatalyst than MoS 2 for H 2 evolution and stability. We note MoS 2 is an earth-abundant robust cocatalyst previously recognized as an ideal substitute for Pt. Importantly, this research work also provides new insights for the design and practical manufacture of low-cost highly efficient H 2 generating photocatalysts by ultra-thin 2D materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Ti 0.5 Ru 0.5 O 2 /TiO 2 (B)/TiO 2 (A) nanosheets are constructed. • The nanosheets exhibits a remarkable photothermal synergistic H 2 evolution rate. • Ti 0.5 Ru 0.5 O 2 shows much better co-catalytic ability compared to Ru and RuO 2. TiO 2 is an important material used in photocatalytic H 2 evolution. Here nanosheets with a Ti 0.5 Ru 0.5 O 2 /TiO 2 (B)/TiO 2 (A) three-phase-junctions, composed of solid solution rutile phase Ti 0.5 Ru 0.5 O 2 , bronze phase TiO 2 (B), and anatase phase TiO 2 (A), are constructed via a hydrothermal method and subsequent calcination. At the optimal calcination temperature of 350 °C, the highest H 2 evolution rate reaches 27.817 mmol∙g−1∙h−1 at 25 °C, which is further increased up to 62.357 mmol∙g−1∙h−1 at 70 °C by synergistic photothermal catalysis. The photocatalytic activity of the optimized catalyst was further enhanced by loading with Pt as a co-catalyst. It is found that, in addition to helping charge separation, migration, and inhibiting the charge recombination, the three-phase-junctions structure is a key to present strong oxidation and reduction ability. Ti 0.5 Ru 0.5 O 2 solid solution has excellent co-catalytic ability, much better than Ru oxide, metallic Ru, as well as Pt. It works as hole acceptor, accelerating the generation and quench of photo induced peroxyl radicals, and thus significantly enhancing the H 2 generation rate. [ABSTRACT FROM AUTHOR]

• Poto-deposited Hexagonal CdS/TiO 2 (B) shows visible light catalytic activity. • Hydrothermal fabricated Cubic CdS/TiO 2 (B) shows only UV light catalytic activity. • The photocorrosion resistance of CdS/TiO 2 (B) can be enhanced by PVP modification. A conventional TiO 2 photocatalyst cannot respond to visible light due to its large band gap. Here, we describe the construction of tandem CdS/TiO 2 (B) nanosheet architectures with visible light H 2 evolution. A type II heterojunction of hexagonal CdS/TiO 2 (B) (PCT) was constructed by photodeposition and CdS dots, with size about 6 nm, were anchored on TiO 2 (B) nanosheets. A second type I heterojunction of cubic CdS/TiO 2 (B) (HCT) was fabricated by a hydrothermal method and CdS nanoparticles, with size about 50 nm, were dispersed on TiO 2 (B) nanosheets. Both heterojunction systems display remarkable enhancement of H 2 evolution activity under full spectrum irradiation, with highest H 2 evolution rate of 1776 μmol·g−1·h−1 for the photodeposited catalyst and 1494 μmol·g−1·h−1 for the hydrothermal process. The different heterojunction systems show very different H 2 evolution under just visible light irradiation. The highest H 2 evolution (1577 μmol·g−1·h−1) for the type II system is far much higher than the type I (48 μmol·g−1·h−1). The type II system shows more effective utilization of full spectrum with the apparent quantum efficiency in the wavelength range extended from 300 to 500 nm, matching well with the optical absorbance spectrum of the composite catalyst. The structure, morphology, and photocatalytic mechanism of the CdS/TiO 2 (B) composites are discussed. [ABSTRACT FROM AUTHOR]

• 0D/2D Ni 2 P quantum dots/TiO 2 (B) nanosheets architecture was synthesized by a solvothermal method. • Photocatalytic H 2 evolution rate is superior to the noble metal Pt as cocatalyst. • The quantum efficiency of 10% Ni 2 P/TiO 2 (B) nanosheets is as high as 31% at 313 nm. • The H 2 production can be further enhanced 5 times by photothermal synergistic reaction at 90 °C. The development of low cost, stable, robust photocatalysts to convert solar energy into hydrogen energy is an important challenge. Here, we describe a simple solvothermal method to successfully fabricate a catalyst with a hybrid 0D/2D Ni 2 P quantum dot/TiO 2 (B) nanosheet architecture. HRTEM shows that Ni 2 P quantum dots about 5 nm in size were dispersed on ultrathin TiO 2 (B) nanosheets. The optimum photocatalytic H 2 evolution rate with 10 wt% Ni 2 P/TiO 2 (B) (3.966 mmol g−1 h−1) was superior to Pt loaded TiO 2 (B) (3.893 mmol h−1 g−1), which was 15 times higher than pure TiO 2 (B) nanosheets. Significantly, the new catalyst shows high stability and reusability in multiply cycled H 2 production runs for a 30 h period. The H 2 production rate can be considerably increased furthered by using synergistic photothermal H 2 evolution (20.129 mmol g−1 h−1 at 90 °C). [ABSTRACT FROM AUTHOR]