Fig. 7From: A New Phase Change Material Based on Potassium Nitrate with Silica and Alumina Nanoparticles for Thermal Energy StorageSEM images at ×50,000 magnification. SEM images of the nanofluids based on KNO3 with 1.0 wt.% of a silica, b alumina, and c silica-alumina nanoparticlesBack to article page