Functional materials for solar thermophotovoltaic devices in energy conversion applications : a review

Abstract

In recent years, the demand for energy that caters for the socio-economic needs on Earth has led to the use of fossil fuels which currently satisfy over 80% of this demand, however, the drawback of this source of energy includes; lack of economical sustainability and environmental pollution. Consequently, renewable energy sources such as wind, biomass, hydro, geothermal, tidal and solar energy were introduced as alternative consumable fuels to mitigate detrimental climate changes caused by fossil fuels. Furthermore, the abundance of direct sunshine amongst these renewable sources has made solar energy one of the most preferred alternative sources of renewable energy. Solar energy can supply the Earth with the energy it needs because radiant solar energy moves at 186,000 miles per second hence, the energy produced comprising helium and hydrogen gas that touches the Earth in an hour is enough to supply the Earth for an entire year. However, only less than 1% of this energy is extracted and converted to generate electricity, attributed to the challenges of the solar cells. Notably, the conventional conversion of solar energy to electricity is through solar thermal systems and photovoltaics. Nonetheless, there are difficulties in converting the solar energy extracted from these systems to electricity. This literature reviews a comprehensive study of solar thermophotovoltaic devices and the high-tech material used in solar thermophotovoltaic systems as a solution to the conversion challenge by converting the solar energy to heat first, before converting the heat to electricity as opposed the conventional conversion techniques of the direct conversion to electricity.