Li Sijun, Ma Zemian, Fu Mimi, Luo Wei, Yu Yanli, Jiang Yimin, Shen Wei, He Rongxing, Li Ming
Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
J Colloid Interface Sci. 2023 Oct 20;654(Pt B):1089-1097. doi: 10.1016/j.jcis.2023.10.104.
Designing and developing the high activity and long-term durability electrocatalysts for oxygen evolution reaction (OER) has primary significance for breaking the bottleneck of water electrolysis. Herein, an anion/cation-codoped CoS based electrocatalyst, N,Fe-CoS, for the efficient OER was constructed via two-step electrodeposition and low-temperature calcination. The anion and cation optimized significantly the surface electronic structure of N,Fe-CoS and induced synergistically a strong surface electronic polarization along with the generation of abundant Co active sites, which improved considerably the intrinsic catalytic activity. The doping N anion also hindered effectively the catalyst surface oxidation and enhanced the catalytic durability. Benefiting from these, N,Fe-CoS exhibited the outstanding OER activity and catalytic durability, and especially at a high current density, acquired its ultra-low OER overpotential of 261 mV at 300 mA∙cm and maintained continuously a stable current density for 80 h without visible attenuation at 100 mA∙cm. DFT calculations confirmed the cooperative effect of N anions and Fe cations on improving catalytic activity and unveiled that Fe cations in N,Fe-CoS acted a key role in modulating electron densities instead of acting as catalytic sites. This work has an important implication for realizing the synergistic regulation of electron densities of catalytic materials by anions and cations.
设计和开发用于析氧反应（OER）的高活性和长期耐久性的电催化剂对于突破水电解的瓶颈具有重要意义。在此，通过两步电沉积和低温煅烧构建了一种用于高效OER的阴离子/阳离子共掺杂的CoS基电催化剂N,Fe-CoS。阴离子和阳离子显著优化了N,Fe-CoS的表面电子结构，并协同诱导了强烈的表面电子极化，同时产生了丰富的Co活性位点，这大大提高了其本征催化活性。掺杂的N阴离子还有效阻碍了催化剂表面的氧化并增强了催化耐久性。受益于此，N,Fe-CoS表现出出色的OER活性和催化耐久性，特别是在高电流密度下，在300 mA∙cm²时获得了261 mV的超低OER过电位，并且在100 mA∙cm²时连续保持稳定的电流密度80小时而无明显衰减。DFT计算证实了N阴离子和Fe阳离子在提高催化活性方面的协同作用，并揭示了N,Fe-CoS中的Fe阳离子在调节电子密度方面起关键作用，而不是作为催化位点。这项工作对于实现阴离子和阳离子对催化材料电子密度的协同调控具有重要意义。
