Photocatalytic hydrogen evolution is a promising technique for the direct conversion of solar energy into chemical fuels. Colloidal quantum dots with tunable band gap and versatile surface properties remain among the most prominent targets in photocatalysis despite their frequent toxicity, which is detrimental for environmentally friendly technological implementations. In the present work, all-inorganic sulfide-capped InP and InP/ZnS quantum dots are introduced as competitive and far less toxic alternatives for photocatalytic hydrogen evolution in aqueous solution, reaching turnover numbers up to 128,000 based on quantum dots with a maximum internal quantum yield of 31%. In addition to the favorable band gap of InP quantum dots, in-depth studies show that the high efficiency also arises from successful ligand engineering with sulfide ions. Due to their small size and outstanding hole capture properties, sulfide ions effectively extract holes from quantum dots for exciton separation and decrease the physical and electrical barriers for charge transfer.

Single-atom catalysts with maximum metal utilization efficiency show great potential for sustainable catalytic applications and fundamental mechanistic studies. We here provide a convenient molecular tailoring strategy based on graphitic carbon nitride as support for the rational design of single-site and dual-site single-atom catalysts. Catalysts with single Fe sites exhibit impressive oxygen reduction reaction activity with a half-wave potential of 0.89 V vs. RHE. We find that the single Ni sites are favorable to promote the key structural reconstruction into bridging Ni-O-Fe bonds in dual-site NiFe SAC. Meanwhile, the newly formed Ni-O-Fe bonds create spin channels for electron transfer, resulting in a significant improvement of the oxygen evolution reaction activity with an overpotential of 270 mV at 10 mA cm−2. We further reveal that the water oxidation reaction follows a dual-site pathway through the deprotonation of *OH at both Ni and Fe sites, leading to the formation of bridging O2 atop the Ni-O-Fe sites.

In this work, the influence of the terminating or exposed crystal planes of anatase TiO 2 support on the catalytic activity of Pt/TiO 2 catalysts is reported. Strong effects were observed when using CO oxidation as a probe reaction. The CO oxidation activity over these catalysts ranks in the following order: Pt/TiO 2 -{101} > Pt/TiO 2 -{100} > Pt/TiO 2 -{001}. The combination of in situ X-ray absorption spectroscopy, X-ray emission spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, and density functional theory calculations unravelled a strong interaction between platinum particles and different dominating facets of anatase. The catalytic activity of the Pt/TiO 2 catalysts can be correlated with the spectroscopic/ structural results. Compared to {001} facets, the {100} and {101} facets of TiO 2 can stabilize active highly dispersed Pt species and avoid sintering Pt particles. This finding provides some important insights into understanding the metal−support interfacial interactions of Pt/TiO 2 catalysts for tuning their catalytic performance.

We present a straightforward synthesis of hybrid NiFe–N-CNT–rGO catalysts with promising water splitting performance.

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In this study, DFT-D calculations were performed to explore the role of Cu and Mo loading in the CO conversion mechanism on a two-dimensional g-CN(001) surface. The introduced transition metals, Cu and Mo, significantly changed the electron distribution and band structures of g-CN. Moreover, two possible mechanisms for the reduction of CO to CO have been discussed in detail. We found that the energy barriers of the two mechanisms were largely reduced by Cu and Mo loading, and the dominant reaction path changed on different transition metal-loaded surfaces. Cu/g-CN(001) prefers to directly dissociate CO into CO, whereas cis-COOH is the preferred product of CO reduction on Mo/g-CN(001). Considering the activation barrier and reaction route selectivity, Mo-doped g-CN(001) was identified as a promising candidate for CO conversion. It is concluded that suitable transition metal doping can efficiently reduce the energy barrier and control route selectivity along the reaction paths over the g-CN surface. These findings could provide a helpful understanding of the CO reduction mechanisms and aid in the molecular design of novel g-CN catalysts for CO conversion.

Novel photocatalysts -CdSe quantum dots (QDs)/g-C 3 N 4 - were successfully constructed. The structure, chemical composition, and optical properties of the prepared samples were investigated via a series of characterization techniques. The results indicated that CdSe QDs/g-C 3 N 4 photocatalysts exhibited remarkably enhanced photocatalytic activity for visible-light-induced H 2 evolution compared to pristine g-C 3 N 4 and CdSe QDs and addition of 13.6 wt % CdSe QDs into the composite photocatalyst generated the highest H 2 production rate. The enhanced photocatalytic performance of CdSe QDs/g-C 3 N 4 can be attributed to the synergistic effects of excellent visible absorption and high charge separation efficiency from the heterostructure. This work could not only provide a facile method to fabricate semiconductor QDs-modified g-C 3 N 4 photocatalysts but also contribute to the design for heterostructures.

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