Functionalization of carminic acid, the study of its electrochemical, linear, and nonlinear optical properties as a potential material for optoelectronic applications

A new material obtained from the functionalization of the carminic acid molecule (MCA) with attractive optical and electrochemical properties is reported. The material was obtained by methylation of carminic acid (CA) previously extracted from Dactylopius coccus. MCA was chemically characterized using Fourier transform infrared spectroscopy (FT-IR), electron impact mass spectrometry (EMEI). Linear optical properties were studied through UV?Vis, fluorescence spectroscopies in solution and film, the non-linear optical properties were studied by the Z-scan technique, and the electrochemical characterization was studied by cyclic voltammetry. The results show a decrease in absorption properties and a slight increase in emission of MCA compared to CA. The study by Z scan of CA and MCA denotes a non-linear response with the behavior of saturable absorbers for both molecules. The estimation of the electrochemical bandgap by voltammetry shows a similar value for CA and MCA around 3.07 eV, but with a displacement of the energy levels highest occupied molecular orbital (HOMO)???6.90 eV and lowest unoccupied molecular orbital (LUMO)???3.83 eV, these values indicate that MCA is compatible with the architecture of a typical perovskite cell as an electron transport layer material (ETL). MCA is an attractive material to be used as an additive in optoelectronic devices.