利用低活性载体精确调控活性金属的电子结构是开发高性能电催化剂的有效途径，金属与载体之间高度灵活的电子相互作用可优化催化性能。在此，将Ir纳米团簇(Ir@NC)均匀地负载在氮掺杂炭框架上，制备了一种高效的析氢反应(HER)电催化剂。合成过程是将在900 ℃下退火制备的沸石咪唑盐框架-8(ZIF-8)作为碳源浸入IrCl3溶液中，然后在400 ℃的H2/Ar气氛下进行煅烧还原处理。氮掺杂炭框架的三维多孔结构暴露了更多的活性金属位点，Ir簇和氮掺杂炭载体之间的协同效应有效地调节了 Ir的电子结构，优化了 HER过程。在酸性介质中，Ir@NC表现出显著的HER电催化活性:在10 mA cm-2的条件下，过电位仅为23 mV，具有超低的Tafel斜率(25。8 mV dec-1)，且在10 mA cm-2的条件下可稳定运行24 h以上。制备的电催化剂具有高活性、合成路线简便、可规模化制备等优点，有望成为一种极有前途的候选催化剂用于酸性水裂解进行工业制氢。
Ir nanoclusters on ZIF-8-derived nitrogen-doped carbon frameworks to give a highly efficient hydrogen evolution reaction
The precise change of the electronic structure of active metals using low-active supports is an effective way of devel-oping high-performance electrocatalysts.The electronic interaction of the metal and support provides a flexible way of optimizing the catalytic performance.We have fabricated an efficient hydrogen evolution reaction(HER)electrocatalyst,in which Ir nanoclusters are uniformly loaded on a nitrogen-doped carbon framework(Ir@NC).The synthesis process entails immersing an annealed zeolitic imidazolate framework-8(ZIF-8),prepared at 900 ℃ as a carbon source,into an IrCl3 solution,followed by a calcination-reduction treatment at 400 ℃ under a H2/Ar atmosphere.The three-dimensional porous structure of the nitrogen-doped carbon framework ex-poses more active metal sites,and the combined effect of the Ir clusters and the N-doped carbon support efficiently changes the elec-tronic structure of Ir,optimizing the HER process.In acidic media,Ir@NC has a remarkable HER electrocatalytic activity,with an overpotential of only 23 mV at 10 mA cm-2,an ultra-low Tafel slope(25.8 mV dec-1)and good stability for over 24 h at 10 mA cm-2.The high activity of the electrocatalyst with a simple and scalable synthesis method makes it a highly promising candidate for the in-dustrial production of hydrogen by splitting acidic water.
Ir nanoclustersNitrogen-doped carbon supportElectronic interactionElectrocatalysisHydrogen evolution reaction
国家科技期刊平台
NSTL
万方数据
