Wanli Peng

Parametric design criteria of an updated thermoradiative cell operating at optimal states

An updated mode of the thermoradiative cell (TRC) with sub-band gap and non-radiative losses is proposed, which can efficiently harvest moderate-temperature heat energy and convert a part of heat into electricity. It is found that when the TRC is operated between the heat source at 800 K and the environment at 300 K, its maximum power output density and efficiency can attain 1490 W m−2 and 27.2%, respectively. Moreover, the effects of some key parameters including the band gap and voltage output on the performance of the TRC are discussed. The optimally working regions of the power density, efficiency, band gap, and voltage output are determined. The maximum efficiency and power output density of the TRC operated at different temperatures are calculated and compared with those of thermophotovoltaic cells (TPVCs) and thermionic energy converters (TECs), and consequently, it is revealed that the maximum efficiency of the TRC operated at the moderate-temperature range is much higher than that of the TEC or t...

Using a multi-layer graphene-based emitter to improve the performance of a concentrated solar thermionic converter

A new model of the concentrated solar thermionic converter (CSTIC) with a multi-layer graphene (MLG)-based emitter is established. Based on the formulas of the thermionic emission from the MLG with ABA and ABC stacking orders, the power output and the efficiency of the CSTIC are derived. The performance characteristics of the CSTIC are discussed. It is revealed that the maximum efficiency of the CSTIC with the MLG-based emitter is higher than that with the single layer graphene (SLG)-based emitter, and the operating temperature of the MLG-based cathode is lower than that of the SLG-based cathode. It is important to find that the performances of the CSTIC with the ABA stacked graphene are better than those with the ABC stacked graphene. The optimum surface work function of the MLG-based cathode at the maximum efficiency is larger than the work function of the SLG-based cathode so that the CSTIC with the MLG-based emitter can be experimentally implemented more easily than the CSTIC with the SLG-based emitter.A new model of the concentrated solar thermionic converter (CSTIC) with a multi-layer graphene (MLG)-based emitter is established. Based on the formulas of the thermionic emission from the MLG with ABA and ABC stacking orders, the power output and the efficiency of the CSTIC are derived. The performance characteristics of the CSTIC are discussed. It is revealed that the maximum efficiency of the CSTIC with the MLG-based emitter is higher than that with the single layer graphene (SLG)-based emitter, and the operating temperature of the MLG-based cathode is lower than that of the SLG-based cathode. It is important to find that the performances of the CSTIC with the ABA stacked graphene are better than those with the ABC stacked graphene. The optimum surface work function of the MLG-based cathode at the maximum efficiency is larger than the work function of the SLG-based cathode so that the CSTIC with the MLG-based emitter can be experimentally implemented more easily than the CSTIC with the SLG-based emitter.