Fabrication and characterization of NFMA/FTO electrochemical thin film by electrodeposition and immersion techniques: An effective detector for H2O2 and sunlight-driven MB degradation

Abstract

Surface-confined electroactive nanoscale materials (organometallic semiconductors) are being explored as promising alternatives to traditional inorganic semiconductors for redox processes. In response to widespread non-biodegradable dye pollution causing severe environmental threats, urgent and effective methods for dye elimination or conversion are crucially needed. In this study, we successfully fabricated an electrochemical thin film of N-(ferrocenylmethyl) aniline (NFMA) on a fluorine-doped tin oxide (FTO) electrode using immersion and electrochemical deposition techniques. To characterize the NFMA/FTO electrode, we employed XRD, SEM, and UV–Vis spectroscopy. Our results revealed that the deposited NFMA/FTO films exhibited an amorphous structure, as confirmed by XRD analysis. SEM images demonstrated a uniform distribution of small particles on the FTO surface. UV–Vis spectroscopy showed favorable optical properties, indicating a direct band gap of 2.4 eV for electrodeposition film. The NFMA/FTO thin film outperformed FTO electrodes, exhibiting hydrophobic surfaces with contact angles of 73.89° and 78° for immersion and electrodeposition, respectively. The NFMA/FTO electrode exhibited effective electrochemical catalysis for hydrogen peroxide (H2O2) utilizing ferrocene/ferricenium (Fc/Fc+) as an electron-transfer mediator. Under sunlight irradiation, the NFMA/FTO thin film exhibited remarkable degradation efficiency of Methylene Blue (MB), achieving 78% degradation within a reaction duration of 180 min at a concentration of 1 ppm in a 500 mL. The degradation kinetics were found to follow the pseudo-first-order reaction model, yielding rate constant (k) values of 0.0078 min−1. Our findings highlight the potential of surface-confined electroactive nanoscale materials, particularly the NFMA/FTO system, as a promising avenue for various electrochemical and photocatalytic applications.