Long Zhiyun, Zhao Yuyan, Zhang Chunhui, Zhang Yuheng, Yu Cunming, Wu Yuchen, Ma Jun, Cao Moyuan, Jiang Lei
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
Adv Mater. 2020 Apr;32(17):e1908099. doi: 10.1002/adma.201908099. Epub 2020 Mar 4.
Clean energy generated from total water splitting is expected to be an affordable, sustainable, and reliable resource but it remains a challenge to gain pure fuel with a controllable pathway. Here, a simple and economical strategy that enables in situ separation of H /O product by manipulating the generated gas phases with the aid of multi-bioinspired electrodes is proposed. This versatile electrode is based on a Janus asymmetric foam with dual gradients, i.e., the wettability gradient promotes the one-way gas penetration and the geometry gradient boosts the spontaneous on-surface transport in the horizontal direction, which cooperatively facilitates self-driven 3D bubble transport in an aqueous environment. Benefitting from the 3D bionic electrode, the limited distance between the cathode and the anode can be reduced to 1 mm, and the corresponding current density is enhanced 1.5 times as compared with the common condition. This Janus triangular electrode with dual directionality elucidates 3D smart bubble manipulation during overall water splitting and should offer a great opportunity to develop advanced electrochemical processes toward complicated environments such as confined space and zero gravity.
由全水分裂产生的清洁能源有望成为一种经济实惠、可持续且可靠的资源，但通过可控途径获得纯燃料仍然是一项挑战。在此，提出了一种简单且经济的策略，即借助多生物启发电极操纵生成的气相，实现原位分离氢气/氧气产物。这种多功能电极基于具有双重梯度的Janus不对称泡沫，即润湿性梯度促进单向气体渗透，几何梯度增强水平方向上的自发表面传输，二者协同促进水性环境中的自驱动3D气泡传输。受益于这种3D仿生电极，阴极与阳极之间的有限距离可减小至1毫米，与普通条件相比，相应的电流密度提高了1.5倍。这种具有双向性的Janus三角形电极阐释了全水分裂过程中的3D智能气泡操纵，应为开发针对复杂环境（如受限空间和零重力）的先进电化学过程提供绝佳机会。
