A unique in-situ synthesis approach of formation-deformation-reformation routes lead to high crystalline core-shell Calcium Fluoride (CaF₂) nanoparticles. They were tuned by the solvothermal process to achieve superior antireflection property (>95%) in the broadband region (400–1500 nm) after fabricating films by a dip coating method. These nanoparticles capped by cetyltrimethylammonium bromide (CTAB), to increase the porosity in single layer antireflective (AR) film to reduce the refractive index. This efficient antireflection layer with glass implemented on the c-Si solar cell to measure the efficiency and found out to be an improved performance (>5.7% net enhancement) compared to uncoated glass. In addition, the AR coatings exhibited a good mechanical strength which gives us the direction of future development for practical applications like highly transparent window coatings, optical and solar energy conversion applications.