Kumar Pal Sarvesh, Singh Baghendra, Yadav Jitendra Kumar, Yadav Chote Lal, Drew Michael G B, Singh Nanhai, Indra Arindam, Kumar Kamlesh
Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
Department of Chemistry, Indian Institute of Technology, Banaras Hindu University, Varanasi-221005, India.
Dalton Trans. 2022 Aug 30;51(34):13003-13014. doi: 10.1039/d2dt01971j.
Four new functionalized Ni(II) dithiocarbamate complexes of the formula (1-4) (L = -methylthiophene--3-pyridylmethyl dithiocarbamate, L = -methylthiophene--4-pyridylmethyl dithiocarbamate, L = -benzyl--3-pyridylmethyl dithiocarbamate, and L = -benzyl--4-pyridylmethyl dithiocarbamate) have been synthesized and characterized by IR, UV-vis, and H and C{H} NMR spectroscopic techniques. The solid-state structure of complex 1 has also been determined by single crystal X-ray crystallography. Single crystal X-ray analysis revealed a monomeric centrosymmetric structure for complex 1 in which two dithiocarbamate ligands are bonded to the Ni(II) metal ion in a S^S chelating mode resulting in a square planar geometry around the nickel center. These complexes are immobilized on activated carbon cloth (CC) and their electrocatalytic performances for the oxygen evolution reaction (OER) have been investigated in aqueous alkaline solution. All the complexes act as pre-catalysts for the OER and undergo electrochemical anodic activation to form Ni(O)OH active catalysts. Spectroscopic and electrochemical characterization revealed the existence of the interface of molecular complex/Ni(O)OH, which acts as the real catalyst for the OER. The active catalyst obtained from complex 2 showed the best OER activity achieving 10 mA cm current density at an overpotential of 330 mV in 1.0 M aqueous KOH solution.
合成了四种通式为(1 - 4)的新型官能化二硫代氨基甲酸盐镍(II)配合物（L = -甲基噻吩 - - 3 - 吡啶基甲基二硫代氨基甲酸盐，L = -甲基噻吩 - - 4 - 吡啶基甲基二硫代氨基甲酸盐，L = -苄基 - - 3 - 吡啶基甲基二硫代氨基甲酸盐，以及L = -苄基 - - 4 - 吡啶基甲基二硫代氨基甲酸盐），并通过红外光谱、紫外 - 可见光谱以及氢谱和碳 - 氢相关谱（C{H} NMR）光谱技术对其进行了表征。配合物1的固态结构也已通过单晶X射线晶体学确定。单晶X射线分析表明配合物1具有单体中心对称结构，其中两个二硫代氨基甲酸盐配体以S^S螯合模式与Ni(II)金属离子键合，在镍中心周围形成平面正方形几何结构。将这些配合物固定在活性炭布（CC）上，并在碱性水溶液中研究了它们对析氧反应（OER）的电催化性能。所有配合物均作为OER的预催化剂，并经历电化学阳极活化以形成Ni(O)OH活性催化剂。光谱和电化学表征揭示了分子配合物/Ni(O)OH界面的存在，该界面作为OER的真正催化剂。从配合物2获得的活性催化剂表现出最佳的OER活性，在1.0 M氢氧化钾水溶液中，过电位为330 mV时实现了10 mA cm的电流密度。
