Crystal growth mediated physicochemical properties enhancement of CoMnO3 perovskite nanomaterials and its efficient degradation of organic dyes and pathogenic bacteria under mechanical stimuli

Abstract

Addressing water resource depletion from microbial colonies and pollutants, piezo-catalysis, through mechanical energy harvesting, emerges as a promising advanced oxidation process. This work reports the successful synthesis of rhombohedral CoMnO3 (CMO) perovskite (R3) piezo-catalyst with varying calcination time (2–6 hours), amongst which CMO4 exhibited exceptional performance in degrading organic contaminants and microorganisms. Conventional characterizations through XRD, FTIR, XPS, and Raman spectroscopy established pure-phase formation, supported by Rietveld refinement. The synthesis method facilitated irregular spherical agglomerated morphology with an impressive surface area (41.13 m2g−1). Controllable-sized CMO (5–9 nm) semiconductor-nanoparticles enabled unique physicochemical properties, corroborated with ab initio studies, and were suitable for various optoelectronic applications. Furthermore, the elevation in polarization was confirmed by the remarkable dielectric response in CMO4 at low-frequency (∼0.1 M@40 Hz), explained via the IBLC model and LFDD mechanism. The underlying excellent polarizability of CMO4 led to attaining a high piezo-catalytic efficiency, efficiently removing ∼95% of Congo red within 180 minutes under mechanical stimuli, with a significant rate constant (0.00754 min−1), primarily due to ·OH ROS-generation, suggesting a rapid and effective degradation process. Inspired by this, we applied a piezo-catalytic process for nearly 95% E. faecalis bacterial eradication, marking a first-time use of manganese-based perovskite oxide in piezo-dynamic dye degradation and bacterial elimination.