Eur. Phys. J. Plus (2020) 135: 66
https://doi.org/10.1140/epjp/s13360-019-00025-y

Regular Article

Correlation of heat treatment and the impurities accompanying Ag nanoparticles

¹ Physics Department, Faculty of Science, Cairo University, Giza, Egypt
² Basic Science Department, Higher Institute of Applied Arts 5th Settlement, New Cairo, Egypt
³ Physics Department, Higher Institute of Engineering & Technology, New Cairo Academy, New Cairo, Egypt

^* e-mail: asmaa@sci.cu.edu.eg

Received: 20 May 2019
Accepted: 17 September 2019
Published online: 13 January 2020

Abstract

A facile and rapid wet chemical flash method has been used for the formation of silver nanoparticles (Ag NPs). Silver nitrate, chromium nitrate and urea were used to form the as-prepared Ag NPs and two types of silver chromium oxide impurities due to the energy used in preparation (250 °C) is not enough to decompose these impurities. The types of impurities accompanied by Ag NPs were depended on the heat treatment. The experimental results show that the structural properties of the as-prepared Ag NPs at 250 °C, were accompanied by AgCrO₂ and Ag₂CrO₄, however, at higher annealing temperature 400 °C, Ag NPs were accompanied by AgCrO₂ only. X-ray diffraction patterns showed single-phase spinel structure of both samples. The morphology and the chemical composition of the samples are found out using field emission scanning electron microscopy with energy-dispersive X-ray analysis. The crystallite size and the particle size were found to increase with the increase of the annealing temperature. The magnetic behavior, using a vibrating sample magnetometer, indicated a decrease in the exchange bias happened in the hysteresis loop by increasing the annealing temperature. Moreover, the magnetization (M_s) of Ag NPs was improved by increasing the annealing temperature. The antimicrobial studies of Ag NPs at both temperatures showed strong effect against tested bacteria. The as-prepared Ag NPs showed a strong effective treatment against Candida albicans fungi. On the other hand, Ag NPs at 400 °C showed no effect on the tested fungi. Thus, heat treatment had a correlation on the impurities accompanied by Ag NPs, and also on the magnetic and antimicrobial studies.