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The development of excellent photocatalysts for hydrogen evolution is of great significance to solving the global energy crisis. In this work, a novel 3D hierarchical CdS/NiAl-LDH photocatalyst was fabricated by a facile electrostatic assembly strategy, which was composed of 1D CdS nanorods and 3D flower-like NiAl-LDH microspheres. Under the visible irradiation, the CNA-20 hierarchical photocatalyst presents the optimum hydrogen evolution rate achieved to 3.24 mmol g−1 h−1, which is improved 6.23-fold in comparison with the pure CdS. Through the analysis of energy band structures and first-principles calculation, the type-Ⅱ charge transfer mechanism was proposed. Driven by the built-in electric field, as well as the effect of intimate interface contact of CdS and NiAl-LDH, the photogenerated charge could be achieved rapidly separate and migrate, which effectively promotes the H 2 evolution. This well-designed synergistic 1D/3D interface interaction and provides an economic approach to rationally developing metal-free photocatalysts for hydrogen production. [Display omitted] • A novel 3D hierarchical CdS/NiAl-LDH photocatalyst was fabricated by the electrostatic self-assembly strategy. • The CdS/NiAl-LDH photocatalyst displays excellent H 2 production activity and stability. • DFT calculations helped to explain the charge transfer at the heterojunction interface between CdS and NiAl. • A possible charge transfer mechanism during the photocatalytic H 2 evolution was proposed. [ABSTRACT FROM AUTHOR]

The 1D Mn 0.47 Cd 0.53 S nanorods loaded with 0D CoWO 4 nanoparticles were prepared, in addition, a possible mechanism of the photocatalytic H 2 production activity was proposed. [Display omitted] • CoWO 4 Modified Mn 0.47 Cd 0.53 S was synthesized by simple hydrothermal process. • The CoWO 4 /Mn 0.47 Cd 0.53 S-25 can be used as a low cost catalyst for H 2 evolution. • The CoWO 4 /Mn 0.47 Cd 0.53 S-25 demonstrates excellent H 2 production activity and stability. To enhance the photocatalytic activity, loading proper semiconductor with high efficiency and low cost is one of the most valid approaches. Herein, various amounts of CoWO 4 as a novel metal-free material were loaded on Mn 0.47 Cd 0.53 S (MCS) nanorods for photocatalytic hydrogen production reaction. The CoWO 4 /Mn 0.47 Cd 0.53 S-25 (CW/MCS-25) exhibits the highest hydrogen production rate of 41.53 mmol·h−1·g−1 in the Na 2 S/Na 2 SO 3 system, which is about 2.68 times higher than that of pristine MCS. The Mapping and HRTEM reveals the deposited of CoWO 4 on the MCS. The detailed analyses of XPS, EIS, TRPL spectra and transient photocurrent responses indicate that CoWO 4 and MCS interacted closely and the photogenerated electrons of CoWO 4 can be transferred into MCS. In particular, the introduction of CoWO 4 can further transfer the photogenerated holes of MCS, thereby inhibiting the photocorrosion of MCS and improving photocatalytic activity. This work provides a reference for the exploration of noble metal-free composite material and shows great potential in the photocatalytic application. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel dinuclear cobalt complex with definite structure was successfully synthesized and used as a cocatalyst in a photocatalyst H 2 production system. • This system exhibits an average H 2 evolution rate of 1045 μmol·h−1 within 8 h. • This system can work for 24 h with a TON of 16,400. Photocatalytic water splitting to produce hydrogen has gradually become a research hotspot in recent years, and molecular cocatalysts especially cobalt-based complexes as proton reduction cocatalysts have attracted wide attention due to their high activity and selectivity. In this study, CdS nanorods were employed as photosensitizers, and a novel dinuclear cobalt-bis(thiosemicarbazone) complex with definite structure was used as a cocatalyst to improve visible-light-driven hydrogen evolution. Under the optimum conditions, this noble metal-free system exhibited an average hydrogen evolution rate of 1045 μmol·h−1 in 8 h irradiation. This system could work for 24 h with a TON of 16,400, and the average apparent quantum yield of this system is ∼21% at 420 nm. On the basis of photoelectrochemical studies and electrochemical analysis, we proposed a possible mechanism for hydrogen production in this three-component system. [ABSTRACT FROM AUTHOR]