ROS generation and enhanced biocide activity of AgNbO3 semiconductor: an in-depth theoretical perspective

• Grant number: 22/16840-7
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: April 21, 2023
• End date: February 10, 2024
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Elson Longo da Silva
• Grantee: Marisa Carvalho de Oliveira
• Supervisor: Lourdes Gracia Edo
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Universitat de València, Spain
• Associated to the scholarship: 21/01651-1 - CDMF - Functional Materials Development Center: theoretical study of multifunctional materials with potential antiviral application, BP.PD

Abstract

The study of semiconductor nanomaterials is a vast and fascinating field that has endeared the science community's interest. An exciting direction to solve current challenges that attracted enormous interest in the last decade is focused on designing stimuli-responsive systems incorporating a wide range of effective biocide materials for their functionalization on surfaces capable of killing microorganisms by contact. These nanomaterials exert their effects by affecting the integrity of bacterial cell membranes, releasing metal cations, and leading to oxidative stress via the generation of reactive oxygen species (ROS) on the material surface, inhibiting enzyme activity and DNA synthesis. However, the experimental measures cannot characterize the ROS activity with spatiotemporal information and reveal the correlation between the activity of semiconductor and their specific composition and surface structure, being the theoretical perspective an essential tool to provide an atomic-level description of the fundamental steps associated with the ROS generation and its biocide activity. In this context, first-principles calculations within the density functional theory (DFT) framework will be employed to obtain atomic-level information on AgNbO3 geometry, energetics, and electronic and magnetic properties. In addition, its interactions with O2 and H2O to understand the formation and evolution of ROS from the new perspective of energy and charge transfer processes will be explored for the first time. Overall, this study will allow a complete picture of how ROS evolve and promote their further application in AgNbO3. (AU)