Thermo-electrochemical coupling for room temperature thermocatalysis in pyroelectric ZnO nanorods

•Pyroelectric ZnO nanorods were solvothermally synthesized.•Thermo-electrochemical coupling results from the pyroelectric/electrochemical product.•Decomposition ratio for Rhodamine B is ~ 98.15% under 22-62 °C cold-hot cycle excitation.•There was no decrease in thermocatalytic performance after ZnO being recycled 6 times.•Thermocatalysis of ZnO is potential in utilization of room temperature thermal energy.

A strong thermo-electrochemical coupling in solvothermally-synthesized ZnO nanorods is achieved by combining pyroelectric effects and electrochemical oxidation, and is employed for room temperature thermocatalysis. Under 22-62 °C heating-cooling cycles, ZnO nanorods are shown to possess high thermocatalytic activity for Rhodamine B, resulting in ~ 98.15% decomposition. The active species are shown to be hydroxyl and superoxide radicals generated from the reaction between pyroelectrically-induced charges and the hydroxyl ions/oxygen gas in solution. After being recycled six times, the ZnO shows no decrease in thermocatalytic activity. Thermocatalysis offers a non-toxic, highly efficient, recyclable approach for utilization of thermal energy at room temperature.

Graphical abstractDownload high-res image (411KB)Download full-size image