Zhang Kaiyan, Xu Mingze, Wang Jianying, Chen Zuofeng
Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China.
Nanoscale. 2023 Nov 9;15(43):17525-17533. doi: 10.1039/d3nr04101h.
Seawater electrolysis, taking advantage of the huge seawater resource, holds great promise for sustainable hydrogen generation. Compared to conventional water electrolysis, seawater electrolysis is more challenging because of the more complex and corrosive electrolyte and competitive side reactions, which necessitates the development of highly efficient and stable electrocatalysts. In this study, a self-supporting, highly porous NiFe-PBA (Prussian-blue-analogue) electrocatalyst with a hierarchically hollow nanostructure is introduced, which exhibits impressive catalytic performance towards the oxygen evolution in alkaline seawater electrolytes. In NiFe-PBA, the synergistic interaction between Ni and Fe improves intrinsic conductivity for efficient electron transfer, enhances chemical stability in seawater, and boosts overall electrocatalytic activity. The direct use of self-supporting NiFe-PBA as an electrocatalyst avoids the energy-intensive and tedious pyrolysis procedure during the preparation process while making use of the tailored morphological, structural, and compositional benefits of PBA-based materials. By combining the NiFe-PBA catalyst with the NiMoN cathode, the constructed two-electrode electrolyzer achieved a high current density of 500 mA cm at a low cell voltage of 1.782 V for overall electrolysis of alkaline seawater, demonstrating excellent durability for 100 hours. Our findings have important implications for the hydrogen economy and sustainable development through the development of robust and efficient PBA-based electrocatalysts for seawater electrolysis.
海水电解利用丰富的海水资源，在可持续制氢方面具有巨大潜力。与传统水电解相比，海水电解面临更大挑战，因为其电解质更复杂且具有腐蚀性，同时存在竞争性副反应，这就需要开发高效稳定的电催化剂。在本研究中，引入了一种具有分级中空纳米结构的自支撑、高孔隙率镍铁普鲁士蓝类似物（NiFe-PBA）电催化剂，该催化剂在碱性海水电解质中对析氧反应表现出令人印象深刻的催化性能。在NiFe-PBA中，Ni和Fe之间的协同相互作用提高了本征导电性以实现高效电子转移，增强了在海水中的化学稳定性，并提升了整体电催化活性。直接使用自支撑NiFe-PBA作为电催化剂避免了制备过程中耗能且繁琐的热解程序，同时利用了基于普鲁士蓝类似物材料的定制形态、结构和成分优势。通过将NiFe-PBA催化剂与NiMoN阴极相结合，构建的两电极电解槽在1.782 V的低电池电压下实现了500 mA cm的高电流密度用于碱性海水的整体电解，展现出100小时的优异耐久性。我们的研究结果通过开发用于海水电解的坚固高效的基于普鲁士蓝类似物的电催化剂，对氢经济和可持续发展具有重要意义。
