The application of ZnO nanoparticles as a photocatalyst for wastewater treatment: A review

Journal of Nanoanalysis

مقالات آماده انتشار، پذیرفته شده، انتشار آنلاین از تاریخ 20 فروردین 1401

نوع مقاله: Review Paper

شناسه دیجیتال (DOI): 10.22034/jna.2022.1952953.1295

نویسندگان

Mahdi Sanavi Fard¹؛ Aref Shokri^{* 2}

¹tafresh university

²Jundi-Shapur Research Institute, Dezful, Iran.

چکیده

Ever-increasing environmental pollutions and water scarcity are highly challenging issues that pose formidable obstacles to human beings on all fronts. Hetero-photocatalytic methods which utilized semiconductors as photocatalysts are highly promising and green technologies for the degradation of recalcitrant organic pollutants which cannot be completely removed by conventional treatment processes. In the view of the current scenario, zinc oxide nanostructures have been demonstrated to be predominant photocatalyst candidates for photodegradation because of their cost-effectiveness, non-toxicity, strong oxidation capability, flexibility in synthesizing, earth-abundance nature, easy crystallization, and high performance in the absorption over an extensive fraction of solar spectrum in comparison with titanium dioxide. Nevertheless, bare zinc oxide possesses several intrinsic limitations, like high recombination rate of the photogenerated charge carriers, limited solar light application, photo corrosion, broad bandgap and limited visible light absorption. Moreover, photocatalysts separation from remediated solutions restricts their large-scale applications. In this review paper, the authors briefly discussed basic principles of the zinc oxide photocatalytic process besides various modifications such as coupling with low bandgap semiconductors like metal and non-metal doping, synthesizing with graphene oxide, or reduced graphene oxide and their integration in magnetic materials to successfully addressing aforesaid disconcerting challenges. Moreover, hybridized photocatalytic and membrane systems are explored. Finally, challenges and future research directions are proposed for giving profound and well-defined insights toward reaching fully exploited zinc oxide-based nanoparticles in the field of water and wastewater treatments.

کلیدواژه‌ها

photocatalytic method؛ bandgap؛ electron-hole pairs؛ wastewater treatment؛ zinc oxide and graphene oxide