Synthesis and characterization of copper doped zinc oxide nanoparticles and its application in energy conversion

•Using Cu doped ZnO nanoparticles, thermovoltage of 632 mV has been generated in EC cell.•Storage duration of 47.1 h has been observed using planar lipid membrane.•Energy conversion efficiency of 1.36% has been calculated.

Solar cells, in general, perform under light source of solar influx, while the heat energy of solar radiation remains unutilized. Using an aqueous suspension of copper doped zinc oxide nanoparticles in specially-designed electrochemical cells we have observed significant voltage (maximum 632.0 mV) and storage duration (∼47 h) upon thermal excitation. The cells exhibit reasonable energy conversion efficiency (maximum 1.36%). These cells generate voltage even at room temperature (∼30 °C) and the voltage increases gradually with increasing temperature. When the platinum foil separating the two compartments of the electrochemical cell is replaced by a planar lipid membrane, all the parameters e.g., thermovoltage, storage capacity and the energy conversion efficiency increase significantly.