Heterostructuring assisted trimetallic transition metal phoshide with in situ generated active sites, exhibits superior catalytic activity towards oxygen evolution reaction in alkaline medium.

Finding metal‐free, carbon‐based, highly active, and durable electrocatalyst for oxygen evolution reaction (OER) is essential for the development of electrochemical energy storage and conversion systems. Herein, we report the synthesis of graphitic carbon nitride (g‐C3N4) nanorods using a hydrothermal method. The transformation of bulk g‐C3N4 (denoted as g‐B‐CN) to g‐C3N4 1D nanorods (denoted as g‐CN) endowed the material with abundant active sites, increased electrochemical active surface area, and enhanced charge transfer. g‐CN exhibited high activity and durability in catalyzing the OER. The optimized g‐CN achieved a current density of 10 mA cm−2 at an overpotential of 316 mV vs. RHE in 1 M KOH, with a Tafel slope of 125 mV dec−1. The high catalytic performance of g‐CN is mainly attributed to the abundantly exposed unique active sites originatingfrom the 1D morphology and the presence of an oxidized pyridinic nitrogen; elucidating the important role of elaborate morphology tailoring and co‐doping of heteroatoms in catalyzing the OER.

In this work, three types of alumina‐supported bimetallic Ni−Cu catalysts [Ni−Cu/commercial non‐ordered mesoporous alumina (CMA), Ni−Cu/ordered MA (OMA), and Ni−Cu−OMA] were prepared via different fabrication strategies and investigated in the conversion of levulinic acid (LA) into γ‐valerolactone and 2‐methyltetrahydrofuran (2‐MTHF). This study employed characterization techniques and reactions to reveal the effects of the fabrication strategy on the activities of the catalysts. It was observed that the catalysts constructed on OM supports (Ni−Cu/OMA and Ni−Cu−OMA) displayed superior catalytic performance compared to those constructed on CM supports (Ni−Cu/CMA). Specifically, Ni−Cu−OMA, which was fabricated via the one‐pot evaporation‐induced self‐assembly strategy, exhibited the best catalytic performance, achieving a complete conversion of LA and a high selectivity of 73.0 % toward 2‐MTHF in a solvent‐free reaction environment. The promising activity of Ni−Cu−OMA was ascribed to the well‐dispersed active sites within the framework of the support, the enhanced metal‐support interaction, and the highly efficient exploitation of the synergistic effect between Ni and Cu. Detailed post‐characterization techniques were also employed to highlight the outstanding stability of Ni−Cu−OMA.

The realization of carbon‐neutral energy is regarded a prime challenge as the environment and energy have become two key issues facing modern society. Here, synergistically interfaced transition metal selenides are studied for hydrogen production via urea electrolysis with concurrent environmental treatment. Extremely low overpotentials of 210 mV, 250 mV, and 1.41 V vs. RHE were observed at 100 mA cm−2 for HER, OER and UOR, respectively with a 98.3 % faradaic efficiency. A notably low cell voltage of 1.6 and 1.84 V was required at 200 mA cm−2 for urea and water electrolysis, respectively along with a remarkably stable performance for 4 days. Additionally, A 1.45‐fold increase in H2 production rate was observed for urea electrolysis [26.6 μmol min−1] when compared with water electrolysis [18 μmol min−1] decreasing the power consumption by 37 %. Real human urine electrolysis was conducted with excellent performance requiring a cell voltage of only 1.9 V at 200 mA cm−2, attributed to the synergistic intermediate‐active site interaction, improved charge transfer capability, and slow surface transformation‐induced activation.

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