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Porous Graphitic carbon nitride(pg-C 3 N 4 ) possessing hierarchical pores and lamellar nanostrucutres was synthesized in the absent of templates by pyrolysis of the solution-assisted mixing dual-precursors. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N 2 porosimeter, X-ray photoelectron spectroscopy, UV-Vis andphotoluminescence spectroscopy.The photocatalytic activities of as-prepared materials for degradation of methyl violet were studied. The results show that the as-prepared g-C 3 N 4 consists of well-dispersed layers with uniform sizeand hierarchical (Meso/Macro) pores in the nanosheets, which favor photogenerated electron-hole pairs'separation, and the degradation of methyl violet conforms to the quasi-first-order kinetic model. The porous g-C 3 N 4 synthesized by optimizing precursors' ratios exhibited faster degradation rate than g-CN material in the process of photocatalyzing methyl violet andthe degradation rate was over 93 % after irradiation of 180 min, implying that the as-prepared hierarchically porous g-C 3 N 4 is a high-effective and metal-free photocatalytic material for degradation of pollutants.

As non-noble metal material, molybdenum carbide was considered to be one of the most potential electrocatalysts for hydrogen evolution reaction (HER) due to its similar electron structure to platinum. However,...

Mo2C is one of the promising alternatives to the precious metal catalyst for hydrogen evolution reaction (HER). However, it is still challenging to prepare highly dispersed Mo2C and prevent nanoparticles (NPs) from sintering during high‐temperature carbonization. Herein, a strategy is proposed to realize dual purposes that confine the coalescence of Mo2C NPs and redistribute charge density by regulating N‐doped contents. As‐synthesized molybdenum carbide nanodots are well dispersed on the N‐doped carbon nanolayers, and the size of Mo2C is uniform and less than 5 nm. The HER tests reveal that as‐prepared Mo2C nanodots exhibit excellent electrocatalytic activity for HER and long‐term stability. Theory calculation proves that optimizing N doping amount can tune hydrogen adsorption free energies and redistribute charge density. The present study provides insight into the impact of nitrogen doped in C/Mo2C and also a synthetic route to achieve heteroatom doping and size control for the synthesis of nanocatalysts beyond Mo2C.

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