  Solvent engineering offers fine control over the photovoltaic efficiency,
film morphology, and crystallization quality of perovskite films and also
enables to optimize light transmittance and absorbance in solar cell
applications. In the present work, the band gap and reflectance were reduced
through solvent engineering. We found that perovskite thin films produced using
DMF (Dimethyl formamide) solvent had a band gap that was 0.24 eV less than
those produced using IPA (Isopropyl Alcohol) solvent. Perovskite thin films
produced using DMF solvent also exhibited considerably lower solar spectrum
reflectance.
