Green construction of biochar@NiFeO nanocomposite for highly efficient photocatalytic remediation of pesticides from agriculture wastewater.

The world's attention is drawn to the widespread ingestion, toxicity, and bioaccumulation of the Atrazine (AT) and Endosulfan (ES). Pesticides have been proven to have endocrine-disrupting, genotoxic, and persistent characteristics. In this work, the structural design of green synthesized NiFeO is incorporated in rice husk biochar to form BC@NiFeO nanocomposite. Powder X-ray diffraction and microscopic analysis confirmed the semi-crystalline nature of BC@NiFeO reduced due to the incorporation of amorphous BC. The green BC@NiFeO nanocomposite degraded AT and ES up to 98 % and 92 %, respectively. The maximum degradation achieved by BC@NiFeO nanocomposite with minimum pollutants concentration (50 mg L) with 10 mg catalyst dose at acidic pH in natural sunlight because of the higher negative value of zeta potential (-26.4 mV) and lower band gap (2.5 eV). The degradation process involves first-order kinetics followed by initial Langmuir adsorption. The presence of various radical quenchers (t-BuOH, p-BZQ, NaEDTA) has led to the conclusion that hydroxyl radicals play a significant role in the degradation of the toxic substances AT and ES. Additionally, a green-fabricated BC@NiFeO nanocomposite has exhibited exceptional efficiency in degrading AT and ES pollutants in actual wastewater samples. Furthermore, this nanocomposite has demonstrated outstanding sustainability and cost-effectiveness, maintaining its effectiveness for up to eight cycles without a noticeable reduction in activity. In summary, due to its favorable surface characteristics, the environmentally friendly BC@NiFeO nanocomposite holds excellent promise as a unique and potential photocatalyst for various industrial applications.