含双PNP和O-烷基二硫代磷酸配体的双核镍配合物的合成及其电化学性能

Synthesis and Electrochemical Performance of Dinuclear Nickel Complexes with Bis (PNP) and O-Alkyldithiophosphate Ligands

合成了4种含亚烷基双(二(二苯基膦基)胺(即双PNP)和O-烷基二硫代磷酸的双核镍配合物((CH_(2))_n(N(PPh_(2))_(2))_(2))Ni(S_(2)P{O}OR)_(2)(1:n=4,R=CH_(3);2:n=4,R=C_(2)H_(5);3:n=3,R=CH_(3);4:n=3,R=C_(2)H_(5)),用红外光谱、核磁共振谱和紫外-可见吸收光谱对配合物的结构进行了表征。用X-射线单晶衍射测定了配合物1的单晶结构,配合物1含有两个畸变平面四边形Ni S_(2)P_(2)。用循环伏安法测定了配合物1~配合物4在乙腈中的电化学性能及其在三氟乙酸(TFA)中的电催化性能,电化学测定表明配合物1~配合物4均具有电催化还原TFA制氢的能力。1 mmol·L^(-1)配合物1~配合物4在添加120 mmol·L^(-1)三氟乙酸的乙腈溶液时的电催化制氢的转换频率(TOF)和过电位(η)分别为(442.5~469.5)s^(-1)和(0.89~0.98)V。

Four new dinuclear nickel complexes containing bis(PNP)and O-alkyldithiophosphate ligands,((CH2)n(N(PPh2)2)2)Ni(S2P{O}OR)2(1:n=4,R=CH3;2:n=4,R=C2H5;3:n=3,R=CH3;4:n=3,R=C2H5),have been synthesized and characterized by infrared spectroscopy,nuclear magnetic resonance spectra(1H,13C and 31P NMR),ultraviolet-visible absorption spectroscopy.The single crystal structure of complex 1 is determined by X-ray single crystal diffraction.There are two distorted square-planar coordination of Ni S2P2 in the crystal structure of dinuclear nickel complexes1.Furthermore,the electrochemical behaviors and electrocatalytic activities of complexes 1~complexes 4 for hydrogen evolution have also been investigated by the cyclic voltammetry using trifluoroacetic acid(TFA)as the proton source.The investigation results show that complexes 1~complexes 4 can efficiently electrocatalyze protons reduction to hydrogen.With the addition of 120 mmol TFA to 1 mmol complexes 1~complexes 4 in Me CN,the turnover frequency values of these complex catalysts are estimated to be 442.5 s-1~469.5 s-1 and the relevant overpotentials are 0.89 V~0.98 V.