基于N,P共掺杂碳纳米片的富S空位Co/Co_(9)S_(8)复合物作为双功能催化剂用于可充锌-空气电池

S-Vacancy-Rich Co/Co_(9)S_(8)Composites Based on N,P Co-doped Carbon Nanosheets as a Bifunctional Catalyst for Rechargeable Zn-Air Battery

锌-空气电池由于理论能量密度高、环境友好和安全性高等特性,受到了广泛关注。但锌-空气电池的性能受到阴极氧还原反应(ORR)/析氧反应(OER)缓慢动力学的限制,因此,开发高效双功能催化剂至关重要。采用简单的一步烧结法制备了基于N,P共掺杂碳纳米片的富S空位Co/Co_(9)S_(8)复合物(Co/Co_(9)S_(8)@N,P-C)。利用X射线衍射仪和透射电子显微镜等分析其精细结构和形貌,结果表明,基于N,P共掺杂碳纳米片的Co/Co_(9)S_(8)复合物被成功合成。X射线光电子能谱和电子自旋共振等结果表明,富S空位的Co/Co_(9)S_(8)纳米复合物被成功合成。电化学测试结果表明,该纳米复合材料表现出优异的ORR和OER双功能催化活性(ΔE=0.73 V)。与基于Pt/C+Ir/C贵金属作为阴极催化剂的锌-空气电池相比,以富S空位的Co/Co_(9)S_(8)@N,P-C作为阴极催化剂的锌-空气电池具有1.48 V的开路电压(Pt/C+Ir/C:1.46 V)、80 mW·cm-2的功率密度(Pt/C+Ir/C:87.3 mW·cm-2)以及约170 h的循环稳定性(Pt/C+Ir/C:147 h)。本工作为合理设计用于锌-空气电池的非贵金属基双功能催化剂提供了新的思路。

Rechargeable Zn-air battery has attracted widespread attention due to the high theoretical energy density,environmental friendliness and safety.However,the performance of Zn-air battery was limited by the slow kinetics of oxygen reduction reaction(ORR)/oxygen evolution reaction(OER)on the cathodic electrode.Therefore,it is important to develop efficient bifunctional catalysts.In this work,S-vacancy-rich Co/Co_(9)S_(8)composites based on N,P co-doped carbon nanosheets(Co/Co_(9)S_(8)@N,P-C)was prepared by a simple one-step sintering method.X-ray diffractometer and transmission electron microscopy were used to analyze the crystalline structure and fine morphology.And the results show that Co/Co_(9)S_(8)composites based on N,P co-doped carbon nanosheets were successfully prepared.The results of X-ray photoelectron spectroscopy and electron spin resonance showed that Co/Co_(9)S_(8)nanocomposites with S-vacancy-rich were synthesized.The results of electrochemical testing indicate that the nanocomposites exhibit excellent ORR and OER bifunctional catalytic activity(ΔE=0.73 V).Compared with Zn-air battery prepared based on Pt/C+Ir/C catalyst as cathode,Zn-air battery prepared with S-vacancy-rich containing Co/Co_(9)S_(8)@N,P-C as cathode catalysts have 1.48 V open-circuit voltage(Pt/C+Ir/C:1.46 V),the power density of 80 mW·cm-2(Pt/C+Ir/C:87.3 mW·cm-2)and 170 h cycle stability(Pt/C+Ir/C:146 h).This work provides a new idea for rational design of non-noble metal bifunctional catalysts for Zn-air battery.