A New Family of Layered Metal-Organic Semiconductors: Cu/V-Organophosphonates

Abstract

Herein, we report the design and synthesis of a layered redox-active, antiferromagnetic metal organic semiconductor crystals with the chemical formula [Cu(H2 O)2 V(µ-O)(PPA)2 ] (where PPA is phenylphosphonate). The crystal structure of [Cu(H2 O)2 V(µ-O)(PPA)2 ] shows that the metal phosphonate layers are separated by phenyl groups of the phenyl phosphonate linker. Tauc plotting of diffuse reflectance spectra indicates that [Cu(H2 O)2 V(µ-O)(PPA)2 ] has an indirect band gap of 2.19 eV. Photoluminescence (PL) spectra indicate a complex landscape of energy states with PL peaks at 1.8 and 2.2 eV. [Cu(H2 O)2 V(µ-O)(PPA)2 ] has estimated hybrid ionic and electronic conductivity values between 0.13 and 0.6 S m-1 . Temperature-dependent magnetization measurements show that [Cu(H2 O)2 V(µ-O)(PPA)2 ] exhibits short range antiferromagnetic order between Cu(II) and V(IV) ions. [Cu(H2 O)2 V(µ-O)(PPA)2 ] is also photoluminescent with photoluminescence quantum yield of 0.02%. [Cu(H2 O)2 V(µ-O)(PPA)2 ] shows high electrochemical, and thermal stability.