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Solar-induced overall water splitting to produce hydrogen is inspiring towards energy sustainability, but it is also formidable due to its limited efficiency seriously hindering its scale up for practical application. CdS is an important transition metal sulfide with low-work-function. However, its photostability is often deteriorated due to photocorrosion influence. To overcome this issue, single-atom Pd was employed here to decorate CdS to form a CdS-Pd nanocatalyst through a simple and controllable photoinduced reduction strategy. The synergetic semiconductor (CdS)-metal (Pd) interaction promotes the fast bulk-to-surface electron migration, thereby the resultant CdS-Pd (3.83‰) nanocatalyst shows considerable structural stability and dramatically improved solar-induced HER activity in overall water splitting, about 110-fold higher than that of pristine CdS. Meanwhile, high apparent quantum yields (AQYs) of 4.47%/1.81% and 33.92%/27.49% were respectively achieved with this decorated nanocatalyst under the light of 420 nm/500 nm in absence and presence of scavenger, demonstrating the high-efficiency under broadband light illumination. Density functional theory (DFT) calculation supports that the easy formation of H* intermediates on the decorated nanocatalyst due to low energy barriers accounts for the internal promoted mechanism for hydrogen production. This study provides important insight to gain stable CdS-based photocatalysts for high-efficient hydrogen production by overall water splitting. Fast bulk-to-surface electron migration for overall water splitting under simulated solar light. [Display omitted] • Single-atom Pd was decorated to CdS through a simple and controllable strategy. • Synergetic semiconductor (CdS)-metal (Pd) interaction promotes fast bulk-to-surface electron migration. • High apparent quantum yields were achieved with this decorated nanocatalyst. • Hydrogen production on the decorated nanocatalyst presents low energy barriers. [ABSTRACT FROM AUTHOR]

Construction of 3D porous BN/rGO skeleton embedded by MoS 2 nanostructures for high-efficient hydrogen production under simulated-solar-light. [Display omitted] • The 3D porous structure of BN/rGO skeleton leads to abundant active sites exposure. • The synergetic heterointerface of BNG-MoS 2 composite results in the fast interfacial charge mobility and good photoresponsivity. • Its AQY is basically consistent with its UV–vis absorption spectrum. • The prominent durability and reproducibility were achieved by this catalyst. Solar-induced water splitting is a very promising approach for hydrogen production. Molybdenum disulfide (MoS 2) is an important transition metal sulfide to synthesize high-efficient photocatalysts due to its narrow bandgap. However, the low-crystallinity and serious photo-corrosion of MoS 2 generally leads to the weak structural stability, further resulting in the remarkably decreased photocatalytic performance. Herein, the MoS 2 nanostructures were embedded on the surface of 3D porous BN/rGO (BNG) skeleton to fabricate the 3D BNG-MoS 2 (BNG-M) composite. Due to the typical 3D porous structure and synergetic heterointerface, abundant active sites were exposed, and fast interfacial charge mobility and good photoresponsivity were presented, thereby the optimum 3D BNG-M catalyst presented remarkably enhanced HER rate of 1490.3 µmol·h−1·g−1 under simulated-solar-light (SSL), which is ∼ 58.2 and ∼ 12.2-fold greater of pure MoS 2 and 3D porous BNG skeleton, and is more prominent than many reported MoS 2 and BN based catalysts. Its apparent quantum yields (AQY) is basically consistent with its UV–vis absorption spectrum. Meanwhile, the prominent durability and reproducibility were achieved by this catalyst. This study provides an important insight to construct the photocatalyst with abundant active sites for achieving high-efficient SSL-induced HER activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon-doped 3D porous h-BN/rGO hybrid was constructed in absence of template assistance. • The synergistic effect of h-BN/rGO heterointerface and carbon-doping remarkably enhanced the HER performance. • The photoresponsivity and electrochemical property were remarkably improved. • The excellent HER activity was achieved by the metallic-free carbon-based material. Water splitting by photocatalysis technique is regarded as an eco-friendly hydrogen production strategy. However, the poor photoresponsivity and automatic electron-hole recombination greatly restrict the HER performance of conventional semiconductor photocatalyst. Here, to utilize the stable electrochemical property of hexagonal phase boron nitride (h-BN) and improve its defect of wide bandgap (E g ≈ 4.2 eV), reduced graphene oxide (rGO) was applied to construct three-dimensional (3D) porous h-BN/rGO hybrid accompanied by a carbon-doping strategy without template assistance, then a carbon-doped 3D porous h-BN/rGO (C-BNRG) hybrid with large BET surface area was successfully prepared. As the synergistic effect of h-BN/rGO heterointerface and carbon-doping, the improved photoresponsivity and electrochemical property were presented, and the resultant 3D porous C 0.4 -BNRG hybrid presented not only greatly enhanced HER activity (157.63 μmol·g−1·h−1) but excellent durability in pH = 8.5, which was prominently higher than pristine h-BN (～36.7 times), C-BN (～12.1 times) and 3D porous BNRG hybrid (～7.0 times). This study offers a template-free approach to develop non-metallic based 3D porous hybrid for outstanding HER performance. [ABSTRACT FROM AUTHOR]

Ternary CdS@h-BN/rGO heterostructure with superhigh photocurrent density and fast interfacial conductivity for hydrogen production under simulated solar light. • Structural reconstruction strategy was proposed to construct a ternary CdS@h-BN/rGO catalyst. • The CdS@h-BN heterointerface promoted the electron transfer between h-BN and CdS under photoinduction. • Superhigh photocurrent density was generated on this ternary catalyst under simulated solar light. • This ternary catalyst represented remarkably enhanced HER activity under simulated solar light. • This ternary catalyst represented excellent regenerability and durability. Solar light driven hydrogen evolution is a prospective strategy to solve the energy problem. However, the poor photoresponse, low photocurrent density and easy electron-hole recombination remarkably restrict the HER activity of the conventional photocatalyst. Herein, we constructed a CdS@hexagonal boron nitride (h-BN) heterostructure on reduced graphene oxide (rGO) to synthesize a ternary CdS@h-BN/rGO catalyst via a structural reconstruction strategy. The CdS@h-BN heterointerface promoted the electrons transferring to the CdS active centers from the valence band of h-BN under photoinduction, overcoming the wide bandgap defect of pristine h-BN. The easily photoexcited property of CdS cocatalyst resulted in superhigh photocurrent density (2.7·μA cm−2) under simulated solar light, which was 3.3-fold greater of pristine CdS NPs. Meanwhile, the interfacial interactions of three components remarkably restrained the carriers recombination. Hence, the resultant ternary hybrid catalyst presented remarkably improved photoresponse and interfacial conductivity, thereby the optimal catalyst represented remarkably enhanced HER activity (6465.33 μmol h−1 g−1) under simulated solar light, which was about 10.9-fold greater of the pristine CdS NPs and 218.3-fold greater of the optimal h-BN/rGO hybrid. About 19.8 % of apparent quantum yield was achieved under illumination of λ =420 nm, and the excellent regenerability and durability were represented during six cycles and 20 h of continued illumination. Thereby, this study provides a prospective idea for constructing low-cost nonprecious metal based photocatalyst with highly efficient HER performance. [ABSTRACT FROM AUTHOR]

Schematic illustration of the charge separation and transfer in direct Z-scheme system SiC@Zn 0.5 Cd 0.5 S model under light irradiation. • The SiC@Zn 0.5 Cd 0.5 S core-shell Z-scheme nanostructure was synthesized. • In situ irritated XPS method has proven the Z-scheme system. • The shell thickness controlled the photocatalytic ability. • The hydrogen production rate was enhanced up to 334%. In this article, we for the first time synthesized a series of SiC@Zn 0.5 Cd 0.5 S core-shell Z-scheme nanostructure, with the thickness of the shell varies from 12 nm to 60 nm, and the excellent photocatalytic exists because of the Z-scheme heterojunction mechanism. The Z-scheme system of SiC@Zn 0.5 Cd 0.5 S core-shell structure was proven by the in situ irradiated X-ray photoelectron spectroscopy, the system separated the photo-generated electron-hole pairs, and the core-shell structure performed better photocatalytic properties than Zn 0.5 Cd 0.5 S on the hydrogen production under UV–vis light irradiation. With decreasing of the shell thickness, the transient photocurrent response of the SiC@Zn 0.5 Cd 0.5 S increased and the photoluminescence decreased, anticipating the creation, collection, transportation of electrons/holes increased, and the electrons/holes recombination suppressed. The hydrogen production rate enhanced to 334% comparing with pure Zn 0.5 Cd 0.5 S, showing the advantage of SiC@Zn 0.5 Cd 0.5 S core-shell Z-scheme heterojunction nanostructure. [ABSTRACT FROM AUTHOR]