Solar materials mainly include photovoltaic materials and solar thermal materials. In thermal energy storage, currently the main focus areas are cost reduction of storage material, cost reduction of operation and improvement in the efficiency of energy storage. Applications for the solar thermal materials can be classified as high, medium and low temperature areas. In high temperature side, inorganic materials like nitrate salts are the most used thermal energy storage materials, while on the lower and medium side organic materials like commercial paraffin are most used. Improving thermal conductivity of thermal energy storage materials is a major focus area. Cost effective manufacturing technologies for microencapsulated phase change materials and composite materials are being explored. Optimizing the thermophysical properties like melting point of thermal energy storage materials to suite a given requirement is also explored with techniques like eutectic mixtures and hydrocarbon chain length etc.
Photovoltaic materials, as the main components of solar cells, which help solar cells directly convert solar energy into electricity. Photovoltaic materials can be broadly classified into categories of organic, inorganic and organic-inorganic hybrid.
In light of the growing shortage of fossil fuels and the increase of environmental pollution, it is becoming extremely difficult to ignore the development of clean energy. In recent years, many solar materials with high absorption coefficient have emerged due to their low-cost and high power conversion efficiency potentials given that absorber layers with micron or even nanometer thickness can be fabricated making them suitable for thin-film solar cells on flexible substrates or as part of a tandem cell stack, thus becoming a competitive alternative or complimentary material to silicon solar cells. In conclusion, solar materials are presently regarded as a major component of the future new energy structure and have a very broad application prospect.