Construction of honey bee hive-like CuO/PbO heterojunction photocatalysts with enhanced antibiotic and dye degradation activity under visible light†

Abstract

Effective removal of harmful water pollutants was achieved with the help of a hydrothermally synthesized visible light-activated CuO/PbO heterojunction material. Using a variety of advanced methods, composition and morphological and optical characteristics of the synthesised heterojunction catalyst were investigated. As seen in HRTEM images, the structure of the CuO/PbO heterojunction resembled a honey bee hive. As it is well known that the use of antibiotics and organic dyes has been expanding continuously and their release in water causes contamination of drinkable water, it is essential to create an effective removal strategy for these harmful pollutants. The ability of the synthetic heterojunction to remove amoxicillin (AMX) antibiotic and malachite green dye (MG) from wastewater was tested in the presence of direct sunlight. With the aid of a UV-visible spectrophotometer and the LC-MS technique, experimental tests were carried out to track changes in the target pollutant's concentration over time, and to pinpoint the intermediates formed during the degradation reaction. With rate constant values of 0.0785 min⁻¹ and 0.0989 min⁻¹, the complete removal of AMX and MG pollutants was accomplished in 60 min and 40 min, respectively. Reusability tests showed outstanding photocatalytic activity that was maintained for five consecutive cycles. These results validated the development of an excellent sunlight-activated heterojunction for the removal of wastewater toxins.