Thermal‐to‐Electrical Energy Conversion Cell with Sol–Gel‐Derived TiSn‐Organic Composite Operated without Temperature Difference

Abstract

The authors demonstrate thermally stimulated current densities exceeding 130 mAcm À2 at an operation temperature of 60 C, from a Ti─Sn-organic composite layer sandwiched between Al and Cu electrodes. This phenomenon does not require a temperature difference for operation. Moreover, the device structure is simple. These unique characteristics will be useful for applications in practical energy-harvesting devices in the near future. By optimizing the sintering temperature of the sol-gel process used for synthesizing the Ti─Sn-organic composite, The authors find that the highest current density could be achieved at 300 C. The X-ray photoelectron and Fourier transform infrared spectra indicate that the interaction between Sn and the acetyl group caused efficient thermally stimulated current generation. Sintering at temperatures above 450 C removes the acetyl group from the Ti─Sn-organic composite, which grades the thermal-to-electrical conversion characteristics. The important result of this research is that thermally stimulated current with high current density can be obtained using a Ti─Sn-organic composite.