Synthesis and characterization of chitosan/silver/lignin matrix as host for multiferroic nanoparticles

Multiferroic bio composites are a big propeller in the Materials Engineering field due to their low cost, non-toxicity, and multifunctional properties such as ferroelectricity, ferromagnetism, and ferro elasticity. Lately, multiferroic films have gained researchers’ attention because of their ability to convert solar energy. Their polarization-driven carrier separation and above-band gap generated photovoltages causes such ability. This research entails the synthesis of bio composite thin films made of chitosan/silver/lignin, to develop a host for multiferroic nanoparticles. The chitosan/silver and chitosan/silver/lignin continuous matrix were synthetized via sol casting. Then, multiferroic bismuth ferrite (BFO) nanoparticles were incorporated at various calcium dopant levels: 2%, 5%, and 7%. Our results indicated that the latter was the most favorable weight percentage. Diverse applications are possible due to chitosan’s properties such as antibacterial behavior, high viscosity, and water solubility. Moreover, silver nanoparticles exhibited other properties that can lead to electrical and optical applications. Lignin is a plant-based polymer that contributes to the structural reinforcement of the biomatrix. Mixing the chitosan/silver/lignin matrix allows characterizing the multiferroic nanoparticles. Several measurements such as light absorption and bioluminescence (PL) spectra, electric conductivity, mechanical properties, and band gap measurements is helping us define specific application in energy harvesting and the biomedical field. Furthermore, PL photoluminescence was observed at 363nm for all chitosan/nanoparticle films. The addition of the BFO nanoparticles caused a quenching effect in photoluminescence for 7% nanoparticles. Also, silver/chitosan films content characteristic photoluminescence band of silver were observed at 513 nm. The minimum conductivity obtained was 1.660ms/cm at Tc=20.7C for 7% multiferroic nanoparticles. Bandgap measurements ranged from 4.42ev to 4.23ev at levels of multiferroic nanoparticles were from 0% to 7%, respectively. This research aims to make better functioning materials utilizing bioinspired technology for energy harvesting solution.