Constructing abundant interfaces by decorating MoP quantum dots on CoP nanowires to induce electronic structure modulation for enhanced hydrogen evolution reaction.

Interface engineering is a method of enhancing catalytic activity while maintaining a material's surface properties. Thus, we explored the interface effect mechanism via a hierarchical structure of MoP/CoP/Cu3P/CF. Remarkably, the heterostructure MoP/CoP/Cu3P/CF demonstrates an outstanding overpotential of 64.6 mV at 10 mA cm-2 with a Tafel slope of 68.2 mV dec-1 in 1 M KOH. DFT calculations indicate that the MoP/CoP interface in the catalyst exhibited the most favorable H* adsorption characteristics (-0.08 eV) compared to the pure phases of CoP (0.55 eV) and MoP (0.22 eV). This result can be attributed to the apparent modulation of electronic structures within the interface domains. Additionally, the CoCH/Cu(OH)2/CF‖MoP/CoP/Cu3P/CF electrolyzer demonstrates excellent overall water splitting performance, achieving 10 mA cm-2 in 1 M KOH solution with a modest voltage of only 1.53 V. This electronic structure adjustment via interface effects provides a new and efficient approach to prepare high-performance hydrogen production catalysts.

Oxygenated Triazine-Heptazine Heterostructure Creates an Enormous Ascension to the Visible Light Photocatalytic Hydrogen Evolution Performance of Porous C3 N4 Nanosheets.

A highly efficient g-C3 N4 photocatalyst is developed by a novel one-pot thermal polymerization method under a salt fog environment generated by heating the aqueous solution of urea and mixed metal salts of NaCl/KCl, namely SF-CN. Thanks to the synergistic effect of the oxygenation and chemical etching of the salt fog, the obtained SF-CN is an oxygenated ultrathin porous carbon nitride with an intermolecular triazine-heptazine heterostructure, meanwhile, shows enlarged specific surface area, greatly enhanced absorption of visible light, narrowed band gap with a lower conduction band, and an increased photocurrent response due to the effective separation of photogenerated holes and electrons, comparing to those of pristine g-C3 N4 . The theoretical simulations further reveal that the triazine-heptazine heterostructure possesses better photocatalytic hydrogen evolution (PHE) capability than pure triazine and heptazine carbon nitrides. In turn, SF-CN demonstrates an excellent visible light PHE rate of 18.13 mmol h-1  g-1 , up to 259.00 times of that of pristine g-C3 N4 .

Network-Like Platinum Nanosheets Enabled by a Calorific-Effect-Induced-Fusion Strategy for Enhanced Catalytic Hydrogenation Performance.

In this paper, we report the construction of network-like platinum (Pt) nanosheets based on Pt/reduced graphite oxide (Pt/rGO) hybrids by delicately utilizing a calorific-effect-induced-fusion strategy. The tiny Pt species first catalyzed the H2-O2 combination reaction. The released heat triggered the combustion of the rGO substrate under the assistance of the Pt species catalysis, which induced the fusion of the tiny Pt species into a network-like nanosheet structure. The loading amount and dispersity of Pt on rGO are found to be crucial for the successful construction of network-like Pt nanosheets. The as-prepared products present excellent catalytic hydrogenation activity and superior stability towards unsaturated bonds such as olefins and nitrobenzene. The styrene can be completely converted into phenylethane within 60 min. The turnover frequency (TOF) value of network-like Pt nanosheets is as high as 158.14 h-1, which is three times higher than that of the home-made Pt nanoparticles and among the highest value of the support-free bimetallic catalysts ever reported under similar conditions. Furthermore, the well dispersibility and excellent aggregation resistance of the network-like structure endows the catalyst with excellent recyclability. The decline of conversion could be hardly identified after five times recycling experiments.

Silver Single-Atom Catalyst for Efficient Electrochemical CO2 Reduction Synthesized from Thermal Transformation and Surface Reconstruction.

We report an Ag1 single-atom catalyst (Ag1 /MnO2 ), which was synthesized from thermal transformation of Ag nanoparticles (NPs) and surface reconstruction of MnO2 . The evolution process of Ag NPs to single atoms is firstly revealed by various techniques, including in situ ETEM, in situ XRD and DFT calculations. The temperature-induced surface reconstruction process from the MnO2 (211) to (310) lattice plane is critical to firmly confine the existing surface of Ag single atoms; that is, the thermal treatment and surface reconstruction of MnO2 is the driving force for the formation of single Ag atoms. The as-obtained Ag1 /MnO2 achieved 95.7 % Faradic efficiency at -0.85 V vs. RHE, and coupled with long-term stability for electrochemical CO2 reduction reaction (CO2 RR). DFT calculations indicated single Ag sites possessed high electronic density close to Fermi Level and could act exclusively as the active sites in the CO2 RR. As a result, the Ag1 /MnO2 catalyst demonstrated remarkable performance for the CO2 RR, far surpassing the conventional Ag nanosized catalyst (AgNP /MnO2 ) and other reported Ag-based catalysts.