Development of photocatalytic coupled zinc–iron oxide nanoparticles via solution combustion for bisphenol-A removal

• Synthesized coupled zinc–iron oxide via solution combustion technique.
• Coupled zinc–iron oxide with 1:4 ratio of zinc to iron exhibits highest surface area and smallest particle size.
• 35% of BPA removal achieved under UV-A illumination.

Photocatalytic degradation is one of the advance oxidation processes (AOPs) that holds promising potential to solve the existing environmental issues, especially for hazardous wastewater treatment. In this study, solution combustion process is carried out to prepare coupled zinc–iron oxide nanoparticles that endowed with synergetic photocatalytic properties. The p–n junction created through the coupling of zinc oxide and iron (III) oxide is the key feature to maximize the photocatalytic activity of the resultant photocatalyst. The particle size of the synthesized coupled zinc–iron oxide photocatalysts falls in the range of 21–27 nm and the band gap has been reduced from 3.2 eV to 2.07 eV compared to the pristine zinc oxide nanoparticles. The results obtained also indicated that the increase of iron content in the coupled zinc–iron oxide could effectively reduce the band gap of the resultant photocatalyst. The prepared coupled zinc–iron oxide demonstrated promising photodegradation of bisphenol-A upon the irradiation of UV light.