You are not really creating energy, but transforming it from one form to another. For example, many of the ways we generate electricity use the heat generated by combustion or nuclear decay to generate steam to drive generators. Thermocouples generate electricity directly from heat, but usually not much. Nevertheless, some nuclear batteries directly convert heat energy into electrical energy, but the efficiency is not high.Now researchers have developed A method of preparing materials that are better at transformation: tin selenide.
As we all know, tin selenide has good properties of converting heat into electrical energy in its crystal form. However, practical applications are more likely to use polycrystalline forms, whose conversion performance is known to decrease.
This material works well because its thermal conductivity is not very good, and it has a favorable energy band structure that allows multiple energy bands to participate in charge transport. However, in the polycrystalline configuration, the results are not good due to the higher thermal conductivity. However, crystalline tin selenide is difficult to manufacture and is not very stable in actual use.
The team found that the thermal properties of polycrystalline materials are caused by the tin oxide film on the surface. Using a specific construction method, you can remove tin oxide and improve performance, even better than the crystal version of tin selenide.
However, creating this material may be beyond the scope of your garage laboratory. You need a fused silica furnace that can achieve a very tight vacuum. Although you may be able to swing it. Otherwise, you may stick to more traditional methods.