Nanoparticle Superlattices as Efficient Bifunctional Electrocatalysts for Water Splitting
Nanoparticle Superlattices as Efficient Bifunctional Electrocatalysts for Water Splitting
复制标题
纳米粒子超晶格作为高效双功能水分解电催化剂
DOI：
10.1021/jacs.5b07756
复制
发表时间：
2015-11-18
影响因子：
15
通讯作者：
Zheng, Gengfeng
中科院分区：
文献类型：
--
作者：
Li, Jun;Wang, Yongcheng;Zheng, Gengfeng
这种太阳能驱动的水分解过程对于替代能源利用极具吸引力，然而开发用于析氧反应和析氢反应的高效、地球储量丰富的双功能催化剂一直是一项重大挑战。在此，我们开发了一种有序的CoMno@CN超晶格结构作为一种高效的双功能水分解电催化剂，其中均匀的钴锰氧化物（CoMnO）纳米颗粒被一层薄而连续的氮掺杂碳（CN）框架所包覆。CoMnO纳米颗粒通过有效的电子结构配置实现了优化的析氧反应活性，并且CN框架作为一种优异的析氢反应催化剂。重要的是，有序的超晶格结构有利于增强反应位点、高效的电荷转移和结构稳定性。这种双功能超晶格催化剂在整体水分解中表现出优化的电流密度和电化学稳定性，优于大多数先前报道的单功能或双功能电催化剂。与硅光伏电池相结合，这种CoMnO@CN超晶格双功能催化剂能够在无需辅助的情况下连续进行太阳能水分解约5天，太阳能到氢气的转换效率约为80%。我们的发现表明，这些基于过渡金属氧化物的超晶格可作为一种独特的结构形式，用于具有规模化潜力的高效双功能水分解电催化剂。
This solar driven water splitting process is highly attractive for alternative energy utilization, while developing efficient, earth-abundant, bifunctional catalysts for both oxygen evolution reaction and hydrogen evolution reaction has remained as a major challenge. Herein we develop an ordered CoMno@CN superlattice structure as an efficient bifunctional water-splitting electrocatalyst, in which uniform Co-Mn oxide (CoMnO) nanoparticle are coated with a thin, continous nitrogen-doped carbon (CN) framework. The CoMnO nano-particles enable optimized OER activity with effective electronic structure configuration and the CN framework serves as an excellent HER catalyst Importantly, the ordered superlattice structure is beneficial for enhanced reactive sited, efficient charge transfer, and structural stability. This bifunctional superlattice catalyst manifests optimized current densities and electrochemical stability in overall water splitting outperforming most of the previously reported single or bifunctional electrocatalysts. Combining with a silicon with a silicon photovoltaic cell, this CoMnO@CN superlattice bifunctional catalyst enables unassited solar water splitting continously for similar to 5 days with a solar-to-hydrogen conversion efficiency of similar to 80%. Our discovery suggests that these transition metal oxide-based superlattices may serve as a unique structure modality for efficient bifunctional water splitting electrocatalysts with scale-up potentials.