Executive Summary : | The increasing population occupancy in urban areas is predicted to reach 70% by the middle of the century, leading to a 2% increase in energy consumption. This trend is largely due to the construction of high-rise buildings with glass facades, which underperforms building energy efficiency. To address climate change, new technologies such as thermochromic smart windows and radiative cooling are needed. This research focuses on the design and development of Vanadium dioxide (VO2) nanoparticles and their composites for new generation thermochromic smart windows and radiative cooling devices. VO2 is highly promising due to its remarkable metal to insulator transitions above a critical temperature, which can modulate solar heat radiation. These windows can significantly reduce building-related CO2 emissions by reflecting/scattering and emitting heat radiation passively without external energy. Radiant cooling devices reflect solar energy and emit heat radiation from the object to the earth's atmospheric window, reducing buildings' energy consumption through heating, ventilation, and air conditioning (HVAC), which accounts for 35-40% of total energy. The research will be executed in three main steps: design and manufacture, testing and optimization, and proposing scale-up strategies. The focus will be on tuning the nanoparticle shape and intrinsic strain through highly anisotropic and core-shell designs. The materials will be applied as a coating or retrofitted on windows in buildings and houses, with further outdoor testing and scale-up designs explored to modulate heat radiation and increase energy efficiency. |