Cu_2O-SnO/poly(3,4-ethylenedioxythiophene) nanocomposites with core-shell structures and their electrochemical characteristics

摘要

Cu_2O-SnO/poly(3,4-ethylenedioxythiophene, PEDOT) nanocomposites (CSPs) were synthesized by polymerizing a mixture consisting of Sn(II) acetate and Cu(II) acetate as metal precursors, EDOT as the monomer, and cerium(IV) sulfate as the oxidant. Three kinds of CSPs (SnO-rich, homo-phase, and Cu_2O-rich CSP) with different contents of metal precursors formed the core-shell structures, in which the metal oxides and metals were encapsulated by PEDOT. The homo-phase CSP consisted of low crystalline Cu_2O, amorphous SnO, and nanosized Cu within PEDOT, while both the SnO-rich CSP and Cu_2O-rich CSP were composed of high crystalline SnO and Cu_2O without Cu nanoparticles. The homo-phase CSP showed excellent discharge and charge capacities of 988.38 and 876 mAh g~(-1) in the second cycle, representing high reversibility compared to the other two samples. This is caused by (i) the nanostructured formation by low crystalline Cu_2O, amorphous SnO, and nanosized Cu, (ii) the increase of electrical conductivity by nanosized Cu, (iii) the buffering role by PEDOT, and (iv) the formation of a fully interconnected pore structure.