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The rational design of highly efficient and stable electrocatalysts for the oxygen evolution reaction (OER) is an urgent need but remains challenging for various sustainable energy systems. How to adjust the atomic structure and electronic structure of the active center is a key bottleneck problem. Accelerating the electron transfer process and the deep self-reconstruction of active sites could be a cost-effective strategy toward electrocatalytic OER catalyst development. Here, a crystalline−amorphous (c−a) coupled Ni 3 S 2 /NiP x electrocatalyst self-supported on nickel foam with an intimate interface was developed via a feasible solvothermal-electrochemistry method. The coupling interface of the crystalline structure with high conductivity and amorphous structure with numerous potential active sites could regulate the electronic structure and optimize the adsorption/desorption of Ocontaining species, ultimately resulting in high OER catalytic performance. The obtained Ni 3 S 2 /NiP x /NF presents a low OER overpotential of 265 mV to obtain 10 mA•cm −2 and a small Tafel slope of 51.6 mV•dec −1 . Also, the catalyst with the coupled interface exhibited significantly enhanced long-term stability compared to the other two catalysts, with <5% decay in OER activity over 20 h of continuous operation, while that of Ni 3 S 2 /NF and NiP x /NF decreased by about 30 and 50%, respectively. This study provides inspiration for other energy conversion reactions in optimizing the performance of catalysts by coupling crystalline− amorphous structures.

We first report that the red fluorescence of leaves-derived carbon dots is derived from chlorophyll, and a possible formation structure is proposed. By controlling the solvothermal reaction temperature, the new...

Cobalt phosphides modified by nitrogen-doped carbon quantum dots (CoP−NCQDs) were successfully constructed by a facile and low-cost hydrothermal treatment, which is expected to replace traditional noble-metal oxygen evolution reaction electrode materials. Detailed experiments and findings show that nitrogen-doped carbon quantum dots (NCQDs) have a significant impact on the morphology of the CoP catalyst, and nitrogen doping can regulate the surface-active sites to obtain the catalyst with abundant structural defects. Simultaneously, nitrogen doping can regulate the content of pyridinic N and pyrrolic N, which exerts positive effects on the formation of the bond structure and electron conduction between NCQDs and CoP.

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