Wang Xue, Li Kai, Yang Di, Yang Xiaolong, Xiao Meiling, Zheng Lirong, Xing Wei, Liu Changpeng, Zhu Jianbing
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, P. R. China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.
Small. 2024 Jul;20(27):e2310250. doi: 10.1002/smll.202310250. Epub 2024 Jan 31.
The commercialization of rechargeable Zn-air batteries (ZABs) relies on the material innovation to accelerate the sluggish oxygen electrocatalysis kinetics. Due to the differentiated mechanisms of reverse processes, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), rationally integrating dual sites for bifunctional oxygen electrocatalysis is prerequisite yet remains challenging. Herein, multicomponent synergistic active sites within highly graphitic carbon substrate are exquisitely constructed, which is accomplished by fluorine (F) modulation strategy. The incorporation of F dopants facilitates pyridinic N formation for anchoring single metal sites, thus guaranteeing the coexistence of sufficient M-N sites and metal nanoparticles toward bifunctional oxygen electrocatalysis. As a result, the optimal catalyst, denoted as F NH-FeNi-800, outperforms commercial Pt/C+RuO with smaller gap between E = 10 and E (ΔE) of 0.63 V (vs 0.7 V for Pt/C+RuO), demonstrating its superior bifunctionality. Beyond that, its superiority is validated in homemade rechargeable ZABs. ZABs assembled using F NH-FeNi-800 as the air cathode delivers higher peak power density (123.8 mW cm) and long-cycle lifetime (over 660 cycles) in comparison with Pt/C@RuO (68.8 mW cm; 300 cycles). The finding not only affords a highly promising oxygen electrocatalyst, but also opens an avenue to constructing multifunctional active sites for heterogeneous catalysts.
可充电锌空气电池（ZABs）的商业化依赖于材料创新，以加速缓慢的氧电催化动力学。由于氧还原反应（ORR）和析氧反应（OER）等逆过程的机制不同，合理整合用于双功能氧电催化的双位点是先决条件，但仍然具有挑战性。在此，通过氟（F）调制策略，在高度石墨化的碳基底内精心构建了多组分协同活性位点。F掺杂剂的引入促进了吡啶型N的形成，用于锚定单金属位点，从而确保了足够的M-N位点和金属纳米颗粒共存，以实现双功能氧电催化。结果，最佳催化剂F NH-FeNi-800的性能优于商业Pt/C+RuO，其E = 10和E之间的差距更小（ΔE）为0.63 V（Pt/C+RuO为0.7 V），证明了其优异的双功能性。除此之外，其优越性在自制的可充电锌空气电池中得到了验证。与Pt/C@RuO（68.8 mW cm；300次循环）相比，使用F NH-FeNi-800作为空气阴极组装的锌空气电池具有更高的峰值功率密度（123.8 mW cm）和长循环寿命（超过660次循环）。这一发现不仅提供了一种极具前景的氧电催化剂，还为构建多相催化剂的多功能活性位点开辟了一条途径。
