Babar Noor-Ul-Ain, Saddiqa Ayesha, Nisar Laraib, Gilani Syeda Robina, Joya Khurram Saleem
Department of Chemistry, University of Engineering and Technology (UET) GT Road 54890 Lahore Pakistan
Institute of Chemical Sciences, Bahauddin Zakariya University Multan-60800 Pakistan.
RSC Adv. 2019 Nov 14;9(64):37274-37286. doi: 10.1039/c9ra07388d. eCollection 2019 Nov 13.
A highly operative and inexpensive water oxidation scheme using an efficient nanoscale electrocatalyst is vastly demanded for optimum H production, CO reduction, and has attracted increased attention for chemical energy conversion. We present here a simple route to make efficient electrocatalytic colloidal nanoparticles of nickel out of mere metal ions in a simple borate buffer system. The simple and annealed Ni-colloidal nanoparticles (Ni-CNPs) resulted in a facile transformation into ultrafine films, which further activated the catalysts, while initiating OER just at the overpotential = 250 mV (1.48 V RHE) under benign conditions. They also showed high porosity and favorable kinetics while displaying impressive Tafel slopes of just 51 mV dec, and a high TOF value of 0.79 s at 0.35 V was observed for Ni-CNPs/FTO. These electrocatalysts also showed long-term stability during the bulk water electrolysis experiment conducted for a continuous 20 hours without notable catalytic degradation, which ensures their economic benefits. The electrochemical data, CVs, kinetic study, short-term durability, extended catalytic stability, SEM analysis, and other supporting data provide compelling evidence that these non-precious, metal-based, electroactive, catalytic, colloidal thin-films (simple and annealed) with nanoscale morphological attributes presented promising catalytic performance under the conditions used herein.
为了实现最佳的氢气生产、一氧化碳还原，迫切需要一种高效且廉价的水氧化方案，该方案使用高效的纳米级电催化剂，并且在化学能量转换方面已引起越来越多的关注。我们在此展示了一种简单的方法，可在简单的硼酸盐缓冲体系中，仅从金属离子制备出高效的镍电催化胶体纳米颗粒。简单的退火镍胶体纳米颗粒（Ni-CNP）可轻松转化为超薄膜，这进一步激活了催化剂，同时在温和条件下，仅在过电位为250 mV（相对于可逆氢电极1.48 V）时引发析氧反应（OER）。它们还显示出高孔隙率和良好的动力学，同时展现出仅51 mV/dec的令人印象深刻的塔菲尔斜率，并且在0.35 V时观察到Ni-CNP/FTO的高周转频率（TOF）值为0.79 s⁻¹。在连续进行20小时的大量水电解实验中，这些电催化剂还表现出长期稳定性，没有明显的催化降解，这确保了它们的经济效益。电化学数据、循环伏安曲线（CV）、动力学研究、短期耐久性、扩展的催化稳定性、扫描电子显微镜（SEM）分析以及其他支持数据提供了令人信服的证据，表明这些具有纳米级形态特征的非贵金属基、电活性、催化胶体薄膜（简单的和退火的）在本文所用条件下具有良好的催化性能。
