Tailored solar collector coatings: Synthesis and characterization of CuFe2O4/PANI nanocomposites

Abstract

This work successfully synthesized CuFe2O4 nanoparticles and CuFe2O4/PANI nanocomposites via a simple chemical precipitation method followed by in-situ polymerization. The main objective is to investigate the solar selective properties of these novel nanomaterials for solar collector applications. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy were used to characterize phase structure and crystallite sizes. Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDS), transmission electron microscopy (TEM), atomic force microscopy (AFM), and UV–vis spectroscopy were performed to examine the morphology and optical characteristics of the nanostructures. XRD confirmed the development of spinel copper ferrite nanoparticles and copper ferrite/PANI nanocomposites with average crystallite sizes of 20.64 ± 4.04 nm, consistent with FT-IR and Raman results. Optical direct band gaps, estimated using Tauc plots, ranged from 2.7 eV to 3.3 eV for copper ferrite nanoparticles and reduced to 2.5 eV–3.0 eV with polyaniline inclusion. Reflectance spectra showed that CuFe₂O₄/PANI nanocomposites exhibited strong solar absorptance (αs) of 95 % in the visible spectrum and reduced emittance (εt) of 1 % in the infrared region, with a superior selectivity of 96.28 %. These nanocomposites can emerge as a novel class of selective coating materials with outstanding selective optical properties.