Sol-gel synthesis of nanostructured ZnO/SrZnO2 with boosted antibacterial and photocatalytic activity

• Published in: Ceramics international 2022-01, Vol.48 (2), p.2394-2405
• Main Authors: Ahmad, Shakoor, Aadil, Muhammad, Ejaz, Syeda Rabia, Akhtar, Muhammad Usman, Noor, Hadia, Haider, Sajjad, Alsafari, Ibrahim A., Yasmin, Ghazala
• Format: Article
• Language: English
• Subjects: Antimicrobial; Congo red; Nanocomposite; Photocatalysis; Sol-gel
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2021.10.020

Due to extensive industrialization, toxic dyes and pathogenic microbes are contaminating water supplies at an alarming rate. This situation is alarming for humans and all other living organisms that directly or indirectly depend upon water. Photocatalysis is the best technique for eliminating harmful dyes and pathogenic microbes from drinking water since it is cost-effective and ecologically acceptable. To improve the effectiveness of the photocatalysis technique, materials researchers must develop an ideal photocatalyst with a narrow-bandgap, a broad absorption range, and efficient charge separation. Here, we adopted a facile sol-gel technique to synthesize a nanostructured ZnO/SrZnO2 composite that acts as an efficient visible light-triggered photocatalyst. The prepared photocatalyst mineralized the azo dye (Congo red, CR) and destroyed the bacterial strain (Escherichia Coli, E-Coli) under visible-light-irradiation. The photocatalytic test findings revealed that the as-prepared ZnO/SrZnO2 composite exhibited a higher photocatalytic efficiency of mineralizing 92.4% of the CR dye as compared to SrZnO2 (57.9%) and ZnO (34.6%). Kinetic analysis revealed that the CR dye degradation rate over ZnO/SrZnO2 nanocomposite was 5.6 times faster than pure ZnO while 2.5 times faster than SrZnO2. Scavenger's experiments proposed that the peroxide free-radical play a key role, while the positively charged holes play a minor role in the mineralization of CR dye. Additionally, the ZnO/SrZnO2 composite also shows better antibacterial action, as it kills E.coli more effectively by interfering with its essential cellular activities/functions. The photocatalytic and antibacterial properties of our manufactured ZnO/SrZnO2 nanocomposite indicate that it has significant potential to mineralize the poisonous dyes and kill pathogenic microbes. [Display omitted]