A simple approach for the synthesis of bi-functional p-n type ZnO@CuFe2O4 heterojunction nanocomposite for photocatalytic and antimicrobial application

Abstract

Photocatalysis is the versatile process that can be applied for water treatment, environmental remediation etc. A facile sonochemical-co-precipitation technique was adopted to prepare CuFe 2 O 4 decorated ZnO heterojunction nanocomposites (NCs). The characterization was done using UV–vis-DRS, TEM, EDAX, SAED , XRD, BET, PL and FTIR . The TEM reveals that the fabricated NCs were cubic in shape. The XRD and SAED analysis confirmed the crystalline nature of prepared NCs. The NCs band gap was determined to be 2.34 eV that facilitates enhanced performance of photocatalysis in visible region. The photocatalytic activity of NCs when irradiated with visible light was evaluated on basis of methylene blue (MB) dye degradation . The t½ for the degradation of 10 mg/L dye by 3 mg of NCs by photocatalysis was determined to be 77 min. The apparent rate constant of NCs was 4–5.1 times higher in NCs than CuFe 2 O 4 and ZnO respectively. At the end of 6 th recycle, the XRD pattern and NCs photocatalytic activity were retained the same as 1 st that denotes the high stable nature of NCs. The results indicate the enhanced activity of fabricated NCs relative to individual ZnO and CuFe 2 O 4 NPs. A possible photocatalysis mechanism was elucidated using charge carriers and free radicals scavengers. It was evident that ⋅OH radical and holes play the major role in dye degradation. The NCs acted as excellent antimicrobial agent against Bacillus subtilis and Escherichia coli . Hence, the investigation reports that ZnO@CuFe 2 O 4 NCs can be used as an efficient photocatalyst and as an antibacterial agent. • p-n type ZnO@CuFe 2 O 4 NCs was synthesized by chemical co-precipitation with ultrasonic assisted method. • The NCs were characterized by UV–vis-DRS, TEM, EDAX, SAED, XRD, BET, PL and FTIR analysis. • The photocatalytic activity was enhanced by 4–5.1 times than individual counter parts. • The mechanism of degradation was elucidated based on scavengers' responses. • The particles exhibited excellent antibacterial activity.