Bi-functional NiFe2O4/SrTiO3 S-scheme heterojunction for eminent performance photocatalytic treatment of sewage effluent and electrochemical hydrazine determination

Abstract

Devising of materials that afforded dual applicability in decontamination and pollutant detection were still a towering challenge owing to the increasing flux of discharge toxic contaminants over the years. Herein, the NiFe2O4 nanoparticles-loaded on cube-like SrTiO3 (NiFe2O4/SrTiO3) composite was fabricated by a two-step hydrothermal approach providing remarkable photocatalytic treatment and electrochemical sensing of noxious pollutants in wastewater. The material traits of the fabricated composite were scrutinized by myriad characterization approaches. The NiFe2O4/SrTiO3 hybrid material demonstrated high surface area of 19.81 m2/g, adequate band gap energy of 2.75 eV, and prominent photoluminescence characteristics. In the presence of visible light, the NiFe2O4/SrTiO3 exhibited profound photocatalysis capability to eliminate sewage effluent-bearing chlortetracycline hydrochloride (CTCH) with 88.6% COD removal in 120 min, outperforming other pure materials. Meanwhile, the toxicity examination of effluent, the possible degradation pathway of CTCH and the proposed photocatalysis mechanism were also divulged. More importantly, the glassy carbon electrode was modified with synergized NiFe2O4/SrTiO3 (NiFe2O4/SrTiO3−GCE) was adopted for the precise quantification of Hydrazine (Hz). The NiFe2O4/SrTiO3−GCE obeyed first-order response for the Hz detection within the range of 1–10 mM: cyclic voltametric: limit of detection (LOD) of 0.119 μM with sensitivity of 18.9 μA μM−1 cm−2, and linear sweep voltametric: LOD of 0.222 μM with a sensitivity of 12.05 μA μM−1 cm−2. The stability and interference of modified electrode were also inspected. This work furnished valuable insights to yield a composite with the prominent S-scheme heterojunction system for quenching of charge carrier recombination and consequently contributing to the future realization into the domains of environmental clean-up and toxic chemical detection.