Electrochemical Reduction and Preparation of Cu-Se Thermoelectric Thin Film in Solutions with PEG

Investigation of Cu(II) and Se(IV) electrochemical reduction processes in solutions with poly(ethylene glycol) (PEG) provides important theoretical guidance for the preparation of Cu-Se alloy films with stronger thermoelectric properties. The results reveal that PEG adsorbing on the electrode surface does not affect the electrochemical reduction mechanism of Cu(II), Se(IV), and Cu(II)-Se(IV), but inhibits the electrochemical reduction rates. The surface morphology and composition change with a negative shift in the deposition potentials. The Cu-Se alloy film, which was prepared at 0.04 V, was alpha-Cu2Se as-deposited and P-type thermoelectric material after annealing. The highest thermoelectric properties were as follows: Seebeck coefficient (alpha) was +106 mu V center dot K-1 and 1.89 times of Cu-Se alloy film electrodeposited in Cu(II)-Se(IV) binary solution without PEG; resistivity (rho) was 2.12 x 10(-3) omega center dot cm, and the calculated power factor (PF) was 5.3 mu W center dot cm(-1)K(-2) and 4.07 times that without PEG.

Automated summary

The investigation of the electrochemical reduction processes of Cu(II) and Se(IV) in solutions with poly(ethylene glycol) (PEG) provides important guidance for the preparation of Cu-Se alloy films with enhanced thermoelectric properties. PEG does not affect the reduction mechanisms but inhibits the reduction rates. The Cu-Se alloy film prepared under specific conditions exhibits strong thermoelectric properties.