Mo‐N bonds effect between MoSx Coupling with CoN for efficient photocatalytic hydrogen production

Synergy of Pd2+/S2--Doped TiO2 Supported on 2-Methylimidazolium-Functionalized Polypyrrole/Graphene Oxide for Enhanced Nitrogen Electrooxidation

The electrosynthesis of nitrate catalyzed by electrochemical nitrogen oxidation reaction (NOR) is considered as an alternative and sustainable approach to the conventional industrial manufacture, but optimizing the electrocatalytic NOR performance and fabricating the efficient NOR electrocatalysts at the design level still encounter great challenges. Herein, unique Pd2+- and S2--doped TiO2 (Pb/S-TiO2) nanoparticles are successfully in situ grown on the surface of 2-methylimidazolium-functionalized polypyrrole/graphene oxide (2-MeIm/PPy/GO), which present the typical hierarchical micro-nanostructures, resulting in the excellent electrocatalytic NOR performance with the highest NO3 - yield of 72.69 µg h-1 mg-1 act. and the maximum Faraday efficiency of 8.92% at 2.04 V (vs reversible hydrogen electrode) due to the synergistic effect of each component. Due to the doping effect, the appropriate oxygen evolution reaction (OER) activity is achieved by Ti-site, where OER principally occurs, providing *O during the non-electrochemical step of NOR, while the electrocatalytic NOR process as the electrochemical conversion of inert N2 to active *NO intermediates mainly occurs at the Pd-site. Especially, the sulfate radicals in situ formed on Pb/S-TiO2@2-MeIm/PPy/GO further promote nitrogen adsorption and decrease the reaction energy barrier, resulting in the acceleration of NOR. It provides theoretical and practical experience for the design and preparation of NOR electrocatalysts.

Self-induced electron attraction center formation with pyrophosphorylation strategy for photocatalytic hydrogen evolution

An integral approach towards augmenting the performance of photocatalytic hydrogen production lies in the induction of charge transfer mediators within the material matrix itself, thereby facilitating swift and efficient charge transfer processes. Here, CoTiO3 is induced to grow its electronic attraction center, CoP3, through a high-temperature phosphatization strategy. CoP3 acts as the active reduction site for the hydrogen evolution reaction and enhances the photocatalytic performance of the pristine catalyst. Compared with pure CoTiO3, the PCTO7 hybrid catalyst with the electronic attraction center CoP3 exhibits a superior photocatalytic performance and good stability. Experimental results show that the hydrogen evolution performance of the PCTO7 hybrid catalyst reaches 56.52 μmol, which is 78 times higher than that of the single catalyst CoTiO3 (0.72 μmol). These results demonstrate that the hybrid catalyst with the self-induced electronic attraction center has a higher light absorption capacity, faster charge carrier dynamics and improved photogenerated charge carrier separation and transfer than pure CoTiO3, resulting in excellent redox capability. DFT calculations provide evidence supporting the topological metal properties of CoP3 as the electron sink center. This study provides a feasible approach for enhancing the photocatalytic performance of a pristine catalyst employing a high-temperature phosphatization-induced electron sink center.