Common-Ion Effect Triggered Highly Sustained Seawater Electrolysis with Additional NaCl Production

Developing efficient seawater-electrolysis system for mass production of hydrogen is highly desirable due to the abundance of seawater.However,continuous electrolysis with seawater feeding boosts the concentration of sodium chloride in the electrolyzer,leading to severe electrode corrosion and chlorine evolution.Herein,the common-ion effect was utilized into the electrolyzer to depress the solubility of NaCl.Specifically,utilization of 6M NaOH halved the solubility of NaCl in the electrolyte,affording efficient,durable,and sustained seawater electrolysis in NaCl-saturated electrolytes with triple production of H_(2),O_(2),and crystalline NaCl.Ternary NiCoFe phosphide was employed as a bifunctional anode and cathode in simulative and Ca/Mg-free seawater-electrolysis systems,which could stably work under 500 mA/cm^(2) for over 100 h.We attribute the high stability to the increased Na^(+)concentration,which reduces the concentration of dissolved Cl-in the electrolyte according to the common-ion effect,resulting in crystallization of NaCl,eliminated anode corrosion,and chlorine oxidation during continuous supplementation of Ca/Mg-free seawater to the electrolysis system.

多硫化钼微网格电极的几何弹跳效应对析氢效率提高的研究

气泡的析出行为在电化学析气反应中具有重要作用.为了研究周期性结构对气泡脱离的影响,我们构建了一维线性构造的多硫化钼微网格电极.结果表明,利用该电极上的气泡融合行为释放出的表面能可诱导气泡弹起,从而实现气泡的快速脱离,消除气泡屏蔽效应.基于优选的40μm凹槽宽度,产生的气泡以融合的方式可使得脱附尺寸显著降低(体积减小65%).通过结构调控权衡融合效率和黏附功,可以提升气泡脱附效率,进而降低欧姆电阻,提升电催化性能.该研究结果为新型催化电极结构的合理设计提供了新思路,促进了催化电极在相关领域的应用.