Photon-enhanced thermionic emission solar cells based on Si, GaAs, and InP

Photovoltaic energy conversion at high temperatures can be realized with photon-enhanced-thermionic-emission (PETE) solar cells. This characteristic allows them to be combined in tandem with thermal concentrated solar power systems. The cathode, which absorbs photons and works as the emitter electrode, is a crucial component of the PETE device. We investigate the utilization of Si, GaAs, and InP as the cathode materials using numerical device models. Simulated absorber characteristics and device efficiencies are presented and discussed. Our simulations show that Si, GaAs, and InP are all promising materials for PETE solar cells, if surface recombination, electron affinities, and thermal stability of these materials can be optimized. GaAs and InP show higher efficiencies than Si due to their higher band gaps and strong photon absorption characteristics