Enhanced electrical potential of thermoelectric power waves by Sb ₂Te₃-coated multiwalled carbon nanotube arrays

Thermoelectric power waves, where multiwalled carbon nanotubes coated with cyclotrimethylene trinitramine (MWCNT/TNA) directly convert chemical energy to electricity, have received considerable attention recently. However, the low Seebeck coefficient of carbon nanotubes has been regarded as a hurdle to increasing the electrical potential. Here, we present Sb₂Te ₃-coated MWCNT arrays prepared by a sputtering method. An analytical model predicts an increase in Seebeck coefficient of the annular multishell structure by ∼75%. The heterostructure coupled with exothermic chemical reaction of TNA demonstrates an increase in peak electrical potential of 175% (∼198 mV), compared with typical outputs of bare MWCNT/TNA (∼72 mV). A serial connection of two repeating units increased the peak potential by up to 406 mV.