Developing highly catalytic active but stable MoS₂ catalyst for electrochemical hydrogen evolution reaction (HER) performance, requires atomic-level tailoring of the electronic structure, but is greatly challenging. Herein, via precisely growing a double-layer MoS₂/graphene hybrid structure encapsulating CoNi nanoalloy (MoS₂/(CoNi@G)), we report both significantly enhanced HER activity and stability by the electrons of the CoNi cores traversing through the graphene to the outmost MoS₂ layer. It achieves 10 mA cm⁻² at a significantly lower overpotential of 150 mV than that of 262 mV over pristine MoS₂ nanosheets, and runs stably for over 10000 cyclic voltammetry cycles. The electron traversing effect efficiently tunes the electronic structures of both edge S sites and in-plane S vacancies, resulting in more appropriate adsorption energy of hydrogen on these active centers. It also induces strong electronic interactions between the MoS₂ and CoNi@G, which stabilizes the outmost MoS₂ layer and thereby significantly improves its catalytic stability.

开发用于电化学氢析出反应（HER）性能的高催化活性但稳定的MoS ₂催化剂，需要对电子结构进行原子级的定制，但具有很大的挑战性。本文中，通过精确生长包裹CoNi纳米合金（MoS ₂ /（CoNi @ G））的双层MoS ₂ /石墨烯杂化结构，我们报道了通过穿过石墨烯的CoNi核的电子显着增强了HER活性和稳定性。最外层的MoS ₂层。与原始MoS ₂相比，它在150 mV的过电势明显低于262 mV的情况下达到10 mA cm ^-2纳米片，并且可以稳定运行超过10000次循环伏安循环。电子穿越效应有效地调整了边缘S位和平面S空位的电子结构，从而在这些活性中心上产生了更合适的氢吸附能。它还会引起MoS ₂和CoNi @ G之间的强电子相互作用，从而稳定最外层的MoS ₂层，从而显着提高其催化稳定性。