Thermophotovoltaic Cells Based on Low‐Bandgap Compounds Available to Purchase

High efficiency TPV GaSb and Ge based cells fabricated by a non‐toxic and inexpensive Zn‐diffusion technique have been developed. GaSb based cells optimised for operation with solar powered photon emitter allowed increasing the efficiencies up to 27–28% at black body temperature > 2000 K assuming 90% reflection of sub‐bandgap photons. Combination of the MOCVD technique or LPE growth and Zn diffusion from the gas phase allows fabricating Ge photocells on the base of the GaAs/Ge heterostructures, which are characterized by high photocurrent and open circuit voltage values. Efficiencies of 13% were obtained in GaAs/Ge TPV cells under the black‐body (1700–2100 K) irradiation assuming the achieved 90% reflection of sub‐bandgap photons.