Abstract:
Water splitting technology can convert renewable energies such as solar and wind into hydrogen energy, which is key to achieving a low-carbon hydrogen economy cycle. However, Pt-based catalysts for hydrogen evolution reaction (HER) are too expensive, thus it needs to develop efficient non-noble metal catalysts as alternatives. Herein, Ni-BDC-loaded carbon cloth (CC) is co-pyrolyzed with urea to obtain a composite structure of carbon nanotubes (CNT) and porous carbon (PC) embedded with W-doped Ni nanoparticles on CC, resulting in NiW-CNT/PC/CC. Benefiting from the synergistic effect between Ni and W, the high conductivity of CNT, and the high mass transfer rate of PC, NiW-CNT/PC/CC exhibits excellent HER activity in KOH, which only requires a low overpotential of 45 mV to drive a current density of 10 mA cm-2 with stability exceeding 40 h. Simulation calculations confirm that the W doping in metal Ni can optimize its electronic structure by lowering the d-band center and weakening hydrogen adsorption, thus reducing its HER barrier.
摘要:
水分解技术可以将太阳能和风能等可再生能源转化为氢能,这是实现低碳氢经济循环的关键。然而,用于析氢反应(HER)的Pt基催化剂过于昂贵,因此需要开发高效的非贵金属催化剂作为替代品。在这里,Ni-BDC负载的碳布(CC)与尿素共热解,以获得碳纳米管(CNT)和在CC上嵌入W掺杂的Ni纳米颗粒的多孔碳(PC)的复合结构,产生NiW-CNT/PC/CC。受益于Ni和W之间的协同效应,CNT的高导电性,和PC的高传质速率,NiW-CNT/PC/CC在KOH中表现出优异的HER活性,只需要45mV的低过电位来驱动10mAcm-2的电流密度,稳定性超过40h。模拟计算证实,在金属Ni中掺杂W可以通过降低d带中心和削弱氢吸附来优化其电子结构,从而减少她的障碍。