Water electrolysis is an advanced and sustainable energy conversion technology used to generate H₂. However, the low efficiency of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) hampers the overall water‐splitting catalytic performance. Here, a hybrid catalyst was constructed from N‐doped CoS₂ nanoparticles on N,S‐co‐doped graphene nanosheets (N−CoS₂/G) using a facile method, and the catalyst exhibited excellent bifunctional activity. Introduction of N atoms not only promoted the adsorption of reaction intermediates, but also bridged the CoS₂ nanoparticles and graphene to improve electron transfer. Moreover, using thiourea as both N‐ and S‐source ensured synthesis of much smaller‐sized nanoparticles with more surface active sites. Surprisingly, the N−CoS₂/G exhibited superior catalytic activity with a low overpotential of 260 mV for the OER and 109 mV for the HER at a current density of 10 mA cm⁻². The assembled N−CoS₂/G : N−CoS₂/G electrolyzer substantially expedited overall water splitting with a voltage requirement of 1.58 V to reach 10 mA cm⁻², which is superior to most reported Co‐based bifunctional catalysts and other non‐precious‐metal catalysts. This work provides a new strategy towards advanced bifunctional catalysts for water electrolysis.

中文翻译：

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掺氮的硫化钴/石墨烯杂化催化剂，用于总水分解。

水电解是用于产生H ₂的先进且可持续的能量转换技术。但是，析氢反应（HER）和析氧反应（OER）的效率低，阻碍了整体的水分解催化性能。在这里，使用一种简便的方法，在N，S共掺杂的石墨烯纳米片（N-CoS ₂ / G）上，从N共掺杂的CoS ₂纳米颗粒构建了一种杂化催化剂，该催化剂具有出色的双功能活性。N原子的引入不仅促进了反应中间体的吸附，而且桥接了CoS ₂纳米粒子和石墨烯可改善电子转移。此外，使用硫脲作为N源和S源可确保合成具有较小表面活性位的小得多的纳米颗粒。令人惊讶地，在电流密度为10mA cm ^{-2的情况下}，N-CoS ₂ / G表现出优异的催化活性，对于OER为260mV且对于HER为109mV的低过电势。组装后的N-CoS ₂ / G：N-CoS ₂ / G电解槽可大大加速总水分解，其电压要求为1.58 V，达到10 mA cm ^-2优于大多数报道的钴基双功能催化剂和其他非贵金属催化剂。这项工作为水电解高级双功能催化剂提供了新的策略。