Low efficiency, short lifetimes, and limited kinds of catalysts are still three fundamental shortcomings that have plagued electrochemical water splitting. Herein, we rationally synthesized a cost-effective Co₃S₄@MoS₂ hetero-structured catalyst that has proven to be a highly active and stable bifunctional catalyst for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in an alkaline environment. The heterostructure was obtained via a first hydrothermal approach to obtain hollow Co₃S₄ nanoboxes based on the ionic exchange reaction between Fe(CN)₆³⁻ of Co-Fe Prussian blue analogue (PBA) and S²⁻ at 120 °C, and the subsequent in situ growth of MoS₂ nanosheets on the surface of Co₃S₄ nanoboxes at an elevated temperature of 200 °C. The synergistic effects between the active and stable HER catalyst of MoS₂ and the efficient OER catalyst of Co₃S₄, as well as the morphological superiority of hollow and core-shell structures, endow Co₃S₄@MoS₂ with remarkable electrocatalytic performance and robust durability toward overall water splitting. As a result, the designed non-noble electrocatalyst of Co₃S₄@MoS₂ exhibits a low overpotential of 280 mV for OER and 136 mV for HER at a current density of 10 mA cm⁻² in an alkaline solution. Meanwhile, a low cell voltage of 1.58 V is achieved by using the heterostructure as both anode and cathode catalysts. This work paves the way to the design and construction of other prominent electrocatalysts for overall water splitting.

低效率，短寿命和有限种类的催化剂仍然是困扰电化学水分解的三个基本缺点。在本文中，我们合理地合成了一种经济高效的Co ₃ S ₄ @MoS ₂异质结构催化剂，该催化剂已被证明是在碱性条件下对于氢释放反应（HER）和氧释放反应（OER）都具有高活性和稳定性的双功能催化剂环境。通过第一种水热方法获得异质结构，以基于Co-Fe普鲁士蓝类似物（PBA）的Fe（CN）₆ ^3-和S ^2-的离子交换反应获得空心的Co ₃ S ₄纳米盒。在120°C下，MoS ₂纳米片随后在200°C的高温下在Co ₃ S ₄纳米盒的表面上原位生长。MoS ₂的活性和稳定HER催化剂与Co ₃ S ₄的有效OER催化剂之间的协同作用，以及中空和核-壳结构的形态优势，使Co ₃ S ₄ @MoS ₂具有出色的电催化性能对整个水分解具有强大的耐用性。结果，设计出了Co ₃ S ₄ @MoS _2的非贵金属电催化剂。在碱性溶液中的电流密度为10 mA cm ^-2时，OER的低过电势为280 mV，HER的低过电势为136 mV 。同时，通过将异质结构同时用作阳极和阴极催化剂，可实现1.58 V的低电池电压。这项工作为整体水分解的其他杰出的电催化剂的设计和构造铺平了道路。