Despite being promising substitutes for noble metal catalysts used in hydrogen evolution reaction (HER), the nonprecious metal catalysts (NPMCs) based on inexpensive and earth-abundant 3d transition metals (TMs) are still practically unfeasible due mainly to unsatisfactory activity and durability. Herein, a highly active and stable catalyst for HER has been developed on the basis of molybdenum-carbide-modified N-doped carbon vesicle encapsulating Ni nanoparticles (MoxC-Ni@NCV). This MoxC-Ni@NCV material was synthesized simply by the solid-state thermolysis of melamine-related composites of oxalate and molybdate with uniform Ni ions doping (Ni@MOM-com). Notably, the prepared MoxC-Ni@NCV was almost the most efficient NPMCs for HER in acidic electrolyte to date. Besides good long-term stability, MoxC-Ni@NCV exhibited a quiet low overpotential that was comparable to Pt/C. Thus, this work opens a new avenue toward the development of highly efficient, inexpensive HER catalysts.

Hydrothermal carbonization (HTC) of carbohydrates is an economic and sustainable technique for the synthesis of carbon materials. However, the assembly of carbohydrates with soft templates is susceptible to hydrolysis, degradation, and relatively high HTC temperature. Thus, it is still challenging to control the HTC/soft templating of carbohydrates and prepare mesoporous carbon with specific properties. Herein, a simple and effective self-transformation strategy is proposed to improve the HTC/soft templating, which introduces an insoluble melamine sulfate into the formation processes. Mechanism studies indicate that the assembly of D-fructose with soft templates is greatly promoted by coassembling with the gradually released melamine sulfate. As a result, carbonaceous composites with a flower-like structure and N-doping were synthesized. Further, ordered mesoporous carbons with N-doping are obtained after calcination. The obtained carbons exhibit outstanding ability for heavy metal adsorption and supercapacitors. Significantly, this self-transformation strategy will open up new avenues for synthesizing carbohydrate-based functional carbons.

The tedious and costly route of the general nanocasting method hinders the commercial application of mesoporous non‐precious metal catalysts based on transition metal‐coordinating nitrogen‐doped carbons (MN/C). Here, a simple, economic and sustainable hydrothermal carbonization (HTC)/soft templating method is demonstrated for the direct preparation of mesoporous FeN/C materials (FeN/MC). By this method, FeN/MC materials with high specific surface area, hierarchically mesoporous structure, and appropriate iron and nitrogen contents are prepared. The optimized FeN/MC materials exhibit superior catalytic performance in the oxygen reduction reaction (ORR) to commercial Pt/C in 0.1 M KOH. This confirms that the materials are one of the most efficient non‐precious metal catalysts for the ORR in alkaline electrolyte. In addition, considerable durability and ORR activity are demonstrated by the FeN/MC materials in 0.1 M HClO4. Thus, this HTC/soft templating method has great promise for the practical application of this kind of non‐precious metal catalysts in the ORR.

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