Transition metal sulfides have been widely used as highly-efficient and low-cost electrocatalysts for water splitting. We performed systematic first-principles studies for the structural stability, hydrogen evolution reaction activity and water dissociation on pristine and decorated Co₃S₄(001) surfaces. We found that the creation of one kind of S-vacancy and its substitution with Sn can be two effective ways to enhance the electrocatalytic performance of the Co₃S₄(001) surface, as well as to drop the energy barrier for water dissociation. The mechanism behind this is the appearance of high spin Co²⁺ atoms adjacent to a vacancy or dopant, which induce magnetism to sulfur atoms and activate more reaction sites. Our results gain insights into modulating and designing new transition metal sulfides for their applications in electrocatalysts.

中文翻译：

---

Co3S4对有效氢释放反应的磁调制

过渡金属硫化物已被广泛用作水分解的高效，低成本电催化剂。我们对原始和装饰的Co ₃ S ₄（001）表面的结构稳定性，氢释放反应活性和水离解进行了系统的第一性原理研究。我们发现，一种S空位的产生及其被Sn取代可以是增强Co ₃ S ₄（001）表面电催化性能以及降低水离解能垒的两种有效方法。其背后的机制是高自旋Co ^2+的出现原子与空位或掺杂剂相邻的原子，这些原子感应磁化硫原子并激活更多的反应位点。我们的研究结果为调节和设计新的过渡金属硫化物在电催化剂中的应用提供了见识。