Enhanced Crystallinity Behavior of Egg White Mediated h-MoO3 Using Acid Precipitation Method for Improved Anti-Bacterial Properties against Multi Drug Resistant Bacteria

Hexagonal molybdenum trioxide (h-MoO3) was synthesized using egg white with MoO3 precursor, which was further treated with nitric acid (HNO3) by solution-based chemical precipitation technique for comparison without treatment. The XRD analysis confirms the formation of metastable phase with hexagonal crystal system for h-MoO3 with and without HNO3 treatment. Subsequently, the result indicate that the HNO3 treated h-MoO3 shows enhanced crystalline behavior compared to untreated h-MoO3. Raman and FTIR analysis confirmed the formation of h-MoO3 where the variation in intensity of the peaks were observed when comparing h-MoO3 with and without HNO3 treatment as well as due to the changes in the crystalline structure of the samples. The band gaps obtained from Tauc plot for the synthesized h-MoO3 with and without HNO3 treatment were 3.17 eV and 3.26 eV, respectively. Observations by HRSEM and HRTEM allowed confirming the formation of nanorod and nanoplate like structures for h-MoO3 treated with and without HNO3, respectively. In addition, the increased crystallinity of the HNO3 treated h-MoO3 was displayed higher anti-bacterial activity than untreated h-MoO3 with zones of inhibition values of 14 ± 1 and 12 ± 1 mm against multi drug resistant (MDR) E. coli and K. pneumoniae, respectively. Subsequently, the quantitative analysis of HNO3 treated h-MoO3 demonstrated 94