中国石油大学葛磊团队近日研究了Co₉S₈中硫空位演化过程中d-p轨道杂化的动态调谐。相关论文于2025年7月15日发表在《结构化学》杂志上。

缺陷工程通过调节电子结构和界面配位显著提高电催化性能，但反应过程中缺陷演化与催化活性之间的动态关系尚不清楚。

研究组表明，DFT计算首次揭示了硫空位浓度对Co₉S₈电子结构的调制作用，预测优化的空位浓度可以实现高效的电催化水分解。实验制备的具有适当硫空位的Co₉S₈具有优异的双功能活性（HER: 164 mV@η₁₀；OER: 297 mV@η₁₀₀）。MCS组装的整体水分解系统在1.57 V（10 mA cm^-2）下稳定运行超过24小时。

实验研究表明，在反应过程中，硫空位优先吸附OH^-，诱导CoOOH活性相的形成。DFT分析进一步表明，OH^-吸附削弱了d-p轨道杂化，优化了氢/氧中间体吸附能垒，最终提高了催化性能。这项工作通过对缺陷动力学、电子结构和催化性能的协同分析，为催化剂的系统开发建立了新的范例。

附：英文原文

Title: Dynamic tuning of d-p orbital hybridization during sulfur vacancy evolution in Co9S8 toward efficient overall water splitting

Author: anonymous

Issue&Volume: 2025-07-15

Abstract: Defect engineering significantly enhances electrocatalytic performance by modulating electronic structures and interfacial coordination, yet the dynamic correlation between defect evolution and catalytic activity during reactions remains unclear. Herein, DFT calculations first revealed the modulation of sulfur vacancy concentrations on Co9S8 electronic structures, predicting that optimized vacancy concentrations enabled highly efficient electrocatalytic water splitting. Experimentally fabricated Co9S8 with appropriate sulfur vacancies exhibited superior bifunctional activity (HER: 164 mV@η10; OER: 297 mV@η100). The MCS-assembled overall water splitting system demonstrated stable operation at 1.57 V (10 mA cm-2) for over 24 hours. Experimental studies illustrated that sulfur vacancies preferentially adsorbed OH- during reactions, inducing the formation of CoOOH active phases. DFT analysis further indicated that OH- adsorption weakened d-p orbital hybridization, optimizing hydrogen/oxygen intermediate adsorption energy barriers and ultimately enhancing catalytic performance. This work establishes novel paradigms for systematic development of catalysts through synergistic analysis of defect dynamics, electronic structures and catalytic performance.

DOI: 10.1016/j.cjsc.2025.100661

Source: http://cjsc.ac.cn/cms/issues/840