Wu Jie, Hou Meilin, Chen Ziliang, Hao Weiju, Pan Xuelei, Yang Hongyuan, Cen Wanglai, Liu Yang, Huang Hui, Menezes Prashanth W, Kang Zhenhui
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, P. R. China.
College of Engineering, Hebei Normal University, Shijiazhuang, 050024, P. R. China.
Adv Mater. 2022 Aug;34(32):e2202995. doi: 10.1002/adma.202202995. Epub 2022 Jul 12.
Developing advanced electrocatalysts with exceptional two electron (2e ) selectivity, activity, and stability is crucial for driving the oxygen reduction reaction (ORR) to produce hydrogen peroxide (H O ). Herein, a composition engineering strategy is proposed to flexibly regulate the intrinsic activity of amorphous nickel boride nanoarchitectures for efficient 2e ORR by oriented reduction of Ni with different amounts of BH . Among borides, the amorphous NiB delivers the 2e selectivity close to 99% at 0.4 V and over 93% in a wide potential range, together with a negligible activity decay under prolonged time. Notably, an ultrahigh H O production rate of 4.753 mol g h is achieved upon assembling NiB in the practical gas diffusion electrode. The combination of X-ray absorption and in situ Raman spectroscopy, as well as transient photovoltage measurements with density functional theory, unequivocally reveal that the atomic ratio between Ni and B induces the local electronic structure diversity, allowing optimization of the adsorption energy of Ni toward *OOH and reducing of the interfacial charge-transfer kinetics to preserve the OO bond.
开发具有卓越的双电子（2e）选择性、活性和稳定性的先进电催化剂对于驱动氧还原反应（ORR）以生产过氧化氢（H₂O₂）至关重要。在此，提出了一种组成工程策略，通过用不同量的BH₄定向还原Ni来灵活调节非晶态硼化镍纳米结构的本征活性，以实现高效的2e ORR。在硼化物中，非晶态NiB在0.4 V时的2e选择性接近99%，在很宽的电位范围内超过93%，并且在长时间下活性衰减可忽略不计。值得注意的是，在实际气体扩散电极中组装NiB时，实现了4.753 mol g⁻¹ h⁻¹的超高H₂O₂产率。X射线吸收和原位拉曼光谱的结合，以及与密度泛函理论的瞬态光电压测量，明确揭示了Ni和B之间的原子比诱导了局部电子结构的多样性，从而优化了Ni对*OOH的吸附能，并降低了界面电荷转移动力学以保留OO键。
