  The thermophotovoltaic cells which convert the low temperature radiation into
electricity are of significance due to their potential applications in many
fields. In this work, Bi2Te3/Si thermophotovoltaic cells which work under the
radiation from the blackbody with the temperature of 300 K-480 K are presented.
The experimental results show that the cells can output electricity even under
the radiation temperature of 300 K. The band structure of Bi2Te3/Si
heterojunctions and the defects in Bi2Te3 thin films lower the conversion
efficiency of the cells. It is also demonstrated that the resistivity of Si and
the thickness of Bi2Te3 thin films have important effects on Bi2Te3/Si
thermophotovoltaic cells. Although the cells' output power is small, this work
provides a possible way to utilize the low temperature radiation.

Applied Physics