Innovation and Development

Patent of New Solar Coatings Granted

Spinel transition metal oxide is an important kind of pigment widely used in solar-thermal energy conversion system. The material with the appropriate energy gap Eg is transparent in the infrared region with lower energy and can absorb energy in visible and near infrared range of sunlight. Novel spinel transition metal oxide was synthesized through the sol-gel self-propagating combustion method by the researchers of Prof. Liu Gang's team in the Lanzhou Institute of Chemical Physics, CAS. The spinel pigment was achieved after heat treatment of this as-burnt powder at a certain temperature. Then spectrally selective paint coatings with this pigment were fabricated by the simple coating technique. The technology obtained the invention patent authorization recently (A preparation method of solar selective coatings using spinel pigment, patent no. : ZL2011102601 89.4). For the sake of homogeneous distribution, the mixture of spinel pigment in nano size, resin, solvents and additives were treated by the ball mill method. After that were achieved after curing process with the mix of curing agent on metal substrate at the room temperature. This spectrally selective coatings exhibit the optimum spectral selectivity (as=0.93~0.95, eT=0.18~0.30), excellent weatherability, good mechnical performance, while the service life is 25 years.