Evaluation of combined pyroelectric/thermoelectric figures of merit in a novel nanocomposite KNNS-Bi2Te3 material

Thermoelectric and pyroelectric materials exhibit top properties for technological applications in electronic, energy conversion, and heat dissipation devices. For the first time, a new equation combining the pyroelectric (F v,sink) and thermoelectric (ZT) figures of merit is reported, which exhibits values of F v,sink = 9.05 × 10 5 V W −1 and ZT = 0.48, respectively. The R&D reported in this article demonstrated the development of a new transformational nano-composite material based on K 0.5 Na 0.5 Nb 0.97 Sb 0.03 O 3 (KNNS)-Bi 2 Te 3 . This novel material exhibits combined pyroelectric and thermoelectric properties separately controlled by a common variable factor, i.e., temperature ( T) . The Seebeck coefficient of the KNNS-Bi 2 Te 3 (50-50) wt% material is S = 1240 μV K −1 , far superior to the Seebeck coefficient S = 122 μV K −1 of pure Bi 2 Te 3 ; this increase in thermoelectric performance for the composite material KNNS-Bi 2 Te 3 (50-50) wt% is due to the incorporation of the ferroelectric component KNNS. In addition, the Bi 2 Te 3 component enables a relaxor effect on the nanocomposite (KNNS)-Bi 2 Te 3 . In summary, the developed nano-composite KNNS-Bi 2 Te 3 (50-50) wt% represents a promising new material with a unique combination of pyroelectric/thermoelectric properties. • Development a new transformational material K 0.5 Na 0.5 Nb 0.97 Sb 0.03 O 3 -Bi 2 Te 3 material. • The pyroelectric/thermoelectric figures of merit for the nanocomposite were calculated. • Values of figures of merit were F v,sink = 9.05x105 V/W and ZT = 0.5 respectively. • New equation combining the pyroelectric-F v,sink and ZT-thermoelectric figures of merit is reported.