Guo Shasha, Yu Maolin, Lee Jinn-Kye, Qiu Mengyi, Yuan Dundong, Hu Zhili, Zhu Chao, Wu Yao, Shi Zude, Ma Wei, Wang Shuangyin, He Yongmin, Zhang Zhengyang, Zhang Zhuhua, Liu Zheng
Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
State Key Laboratory of Mechanics and Control for Aerospace Structures, Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education, and Institute for Frontier Science, Nanjing University of Aeronautics and Astronautics, Nanjing, China.
Nat Commun. 2025 Jan 22;16(1):919. doi: 10.1038/s41467-024-55750-5.
Electrocatalytic gas-evolving reactions often result in bubble-covered surfaces, impeding the mass transfer to active sites. Such an issue will be worsened in practical high-current-density conditions and can cause sudden cell failure. Herein, we develop an on-chip microcell-based total-internal-reflection-fluorescence-microscopy to enable operando imaging of bubbles at sub-50 nm and dynamic probing of their nucleation during hydrogen evolution reaction. Using platinum-interfacial metal layer-graphene as model systems, we demonstrate that the strong binding energy between interfacial metal layer and graphene-evidenced by a reduced metal-support distance and enhanced charge transfer-facilitates hydrogen spillover from platinum to the graphene support due to lower energy barriers compared to the platinum-graphene system. This results in the spatial separation of bubble nucleation from the platinum surface, notably enhancing catalytic activity, as demonstrated in both microcell and polymer electrolyte membrane cell experiments. Our findings offer insights into bubble nucleation control and the design of electrocatalytic interfaces with minimized transfer resistance.
电催化析气反应通常会导致表面覆盖气泡，阻碍传质至活性位点。在实际的高电流密度条件下，这个问题会恶化，并可能导致电池突然失效。在此，我们开发了一种基于片上微池的全内反射荧光显微镜，以实现对小于50纳米的气泡进行原位成像，并在析氢反应过程中对其成核进行动态探测。使用铂界面金属层-石墨烯作为模型体系，我们证明了界面金属层与石墨烯之间的强结合能——由减小的金属-载体距离和增强的电荷转移所证明——由于与铂-石墨烯体系相比具有更低的能垒，促进了氢从铂溢出到石墨烯载体上。这导致气泡成核与铂表面在空间上分离，显著提高了催化活性，这在微池和聚合物电解质膜电池实验中均得到了证明。我们的研究结果为气泡成核控制以及具有最小化转移电阻的电催化界面设计提供了见解。
