text: Solar reflective and heat emissive surfaces can be of various material compositions. However, for widespread application to be feasible, PDRC materials must be low cost, available for mass production, and applicable in many contexts. Most research has focused on PDRC coatings and thin films, which tend to be more available for mass production, lower cost, and more applicable in a wider range of contexts, although other materials may provide potential for diverse applications.
  Some PDRC research has also developed more eco-friendly or sustainable materials, even if not fully biodegradable. Zhong et al. state "most PDRC materials now are non-renewable polymers, artificial photonic or synthetic chemicals, which will cause excessive  emissions by consuming fossil fuels and go against the global carbon neutrality goal. Environmentally friendly bio-based renewable materials should be an ideal material to devise PDRC systems."