Effect of (Fe0.8Cr0.2)2O3 pigment on the optical properties of ZnO–B2O3–SiO2 glass-based coatings for double-glass photovoltaic modules

Abstract

Solving technical issues of light pollution, thermal protection, color aesthetics, and weathering resistance for the coating layer used in double-glass photovoltaic modules of a solar panel, new coating materials were produced using ZnO–B2O3–SiO2 glass frit and (Fe0.8Cr0.2)2O3 pigment. In this work, the crystal structure, the microstructure, the distribution of Fe and Cr elements, the diffusion of element Fe, the adhesion and the optical properties of the coatings have been characterized. The surface roughness of the coatings has a more significant alteration when the (Fe0.8Cr0.2)2O3 content is greater than 49 wt%. For the coating doped with 46 wt% (Fe0.8Cr0.2)2O3, the amount of Fe diffused into the glassy phase gradually increases from 0.17 wt% to 0.54 wt% as the heat-treatment temperature increased from 650 °C to 720 °C. The effects of (Fe0.8Cr0.2)2O3 pigment content and heat-treatment temperature on the optical properties of coatings were explained mainly from the coatings surface roughness, Fe-redox induced pore formation, Fe-diffusion, and formation of large defects surfaced for the coatings.