Abstract:

Two 1,3,5benzenetricarboxylato coordination polymers {［Cu₂(Hbtc)₂(H₂O)₆］·ppz·H₂O}_n(1) and {［Co₂(btc)₂(H₂O)₆］·(H₂ppz)·(H₂O)}_n(2), (H₃btc=1,3,5benzenetricarboxylic acid, ppz=piperazine) have been hydrothermally synthesized and characterized by IR, UV-Vis-NIR,  elemental analysis and X-ray single crystal diffraction. Structural analysis reveals that the two coordination polymers both crystallize in the triclinic system with P-1 space group and both possess the M1btcM2btcM1polymeric zigzagchain structure, but the coordination geometry around metal ions is different and the same organic molecules exhibit different forms. The photovoltaic property was investigated by surface photovoltage spectroscopy (SPS). The results reveal that the two polymers all exhibit surface photovoltage responses under UVVis lightinducement in SPS, and the coordination environment of the metallic ion affect the response scope. The SPS responses were analyzed and assigned by the combination of the energy band theory of semiconductor and crystal field theory.

Key words: Cu/Cocoordination polymer, crystal structure, spectrum, surface photovoltage