Studies On Electrocatalytic Performance Of Transition Metal Complexes For Water Reduction To Hydrogen

Energy issues related to human long-term development are still concerned by all of us.With the common non-renewable fossil energy reduction day by day,scientists are interested in green hydrogen energy since the demand of new renewable energy is promoted sharply.Inspired by the process of hydrogen production naturally and the research of predecessor,complexes conducted electrochemical experiment were prepared by coordination reaction with transition metal salt and organic ligand,and all of the target complexes were provided with the property of water reduction to hydrogen.The present paper did the follows:A ligand,2-tetrahydrofurfurylamino-N,N-bis?2-methylene-4-tert-butyl-6-methyl?phenol?H₂La?was synthesized by the reaction of 2-tert-butyl-4-methyl-phenol and tetrahydrofurfurylamine.H₂La reacts with CoCl₂×6H₂O to give a cobalt complex,[LaCo^?NCMe] 1.Electrochemical studies showed complex 1 acts as an electrocatalyst for hydrogen generation from neutral water with a turnover frequency?TOF?of 160 h-1 at an overpotential of 888 mV.Complex [BzPyN?CH₃?₂]2[Ni?mnt?₂] 2 was prepared by the reaction of [Ni?mnt?₂]2-and [BzPyN?CH₃?₂]+ in proportion to 1:2,and [4-ClBz PyN?CH₃?₂][Ni?mnt?₂] 3 was prepared by the reaction of [Ni?mnt?₂]-and [4-ClBzPyN?CH₃?₂]+ in proportion to 1:1,which formed two nickel complexes with +2 and +3 oxidation state respectively.Electrochemical studies showed both two complexes act as a electrocatalyst for hydrogen generation from neutral water with the TOF of 283 and 504 h-1 respectively at an overpotential of 848 mV,indicated that complex 3 has higher catalytic activity than 2.Electrochemical studies of [?DCAE?₂Cu?H₂O?₂] 4 and [?HLb?CuCl]2×HCl 5 with +2 oxidation state of copper showed both two complexes act as a electrocatalyst for water reduction to hydrogen from neutral buffer with the TOF of 175 and 1473 h-1 respectively at an overpotential 838 m V,which indicated the complex 5 has higher catalytic activity than 4.A ligand,2-tetrahydrofurfurylamino-N,N-bis?2-methylene-4-methyal-6-tert-butyl?phenol?H₂Lc?was synthesized by the reaction of 2,4-difluorophenol and tetrahydrofurfurylamine,another ligand,2-methoxyethylamin-N,N-bis?2-methylene-4-methyal-6-tert-butyl?phenol?H₂Ld?was synthesized by the reaction of 2-tert-butyl-4-methyalphenol and 2-methoxyethylamine.The ligands react with MoCl5 to give two molybdenum complexes [LcMo^??O?₂] 6 and [LdMo^??O?₂] 7 respectively.Electrochemical studies showed both complex 6 and 7 act as a electrocatalyst for hydrogen generation from neutral water with the TOF of 95 and 186 h-1 at an overpotential 888 mV,which indicated complex 7 has higher catalytic activity than 6.