Nickel sulfide (Ni₃S₂) is a promising electrocatalyst because of its good metal conductivity and stability in alkaline medium. However, the reported catalytic activity of Ni₃S₂ is still relatively low. N-doped graphene coated N-doped Ni₃S₂ nanocubes (N-Ni₃S₂@NG) structure was proposed, which is an effective way to improve the catalytic activity of Ni₃S₂. Thanks to the unique structural design and functional integration, the OER and HER in alkaline medium provide 238 mV and 100 mV over potential respectively at 10 mA cm⁻², and 1.53 V ultra-low operating voltage for overall water splitting. In addition, its super stable catalytic activity is also impressive, and the performance loss is negligible after 70 h durability test. These experimental data and analysis show that, the outstanding catalytic activity of N-Ni₃S₂@NG is due to its abundant active centers and good electron transport properties. More broadly, this combination of bifunctional concept and nanoscale stereoscopic design is unique and advantageous, especially suitable for the development of highly active and durable electrocatalysts for energy conversion reactions.

硫化镍（Ni ₃ S ₂）是一种很有前途的电催化剂，因为它具有良好的金属导电性和在碱性介质中的稳定性。然而，报道的Ni ₃ S _{2 的}催化活性仍然相对较低。提出了N掺杂石墨烯包覆N掺杂Ni ₃ S ₂纳米立方体（N-Ni ₃ S ₂ @NG）结构，这是提高Ni ₃ S ₂催化活性的有效途径。由于独特的结构设计和功能集成，碱性介质中的 OER 和 HER 在 10 mA cm ^{-2 下}分别提供 238 mV 和 100 mV 的过电位, 和 1.53 V 超低工作电压，用于整体水分解。此外，其超稳定的催化活性也令人印象深刻，70小时耐久性测试后性能损失可以忽略不计。这些实验数据和分析表明，N-Ni ₃ S ₂ @NG优异的催化活性是由于其丰富的活性中心和良好的电子传输性能。更广泛地说，这种双功能概念和纳米级立体设计的结合是独特而有利的，特别适合开发用于能量转换反应的高活性和耐用电催化剂。