Selective nanofunctionalization of graphene derivatives for catalytic degradation of organophosphates

• Grant number: 25/23397-0
• Support Opportunities: Scholarships in Brazil - Program to Stimulate Scientific Vocations
• Start date: June 22, 2026
• End date: July 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Elisa Souza Orth
• Grantee: Isadora Pires Gomes
• Host Institution: Setor de Ciências Exatas. Universidade Federal do Paraná (UFPR)

Abstract

Organophosphates are highly toxic and exhibit high chemical stability, justifying their use in pesticides and chemical weapons. Our group has focused on developing catalysts for the degradation of these compounds, as well as their detection. Carbon nanomaterials derived from graphene have proven promising supports for nanocatalysts. Graphene oxide's two-dimensional structure contains oxygenated groups such as carboxylic acids, found at the edge of the GO sheet, and epoxides, hydroxyls, and ketones, found in the basal plane of the sheet. These groups can be selectively functionalized, enhancing their properties and expanding their applications. Furthermore, studies show that the functionalization site influences its final catalytic properties, demonstrating that it has a synergistic effect and does not merely act as an inert support. For example, it has been shown that the free carboxylic acid groups of graphene oxide aid in catalysis, mimicking enzymatic active sites. Nanocatalysts can have multiple functions and also act in the adsorption of environmental contaminants or as active materials for pesticide sensors. Several parameters have been studied, such as the effect of changing the oxygenated sites of the functionalized graphene oxide, the nature and quantity of the anchored functional groups, and synthetic parameters (pH, reaction time, solvent, etc.). However, the functionalization of reduced graphene oxide, which can exhibit quite distinct properties, has not yet been focused on. An ongoing master's project by Gabriel Gomes focuses on obtaining graphene-derived nanocatalysts functionalized with amino acids and amine derivatives. These materials have demonstrated, in addition to catalytic capacity, a high capacity as adsorbents for contaminants such as the pesticide itself or nitrophenols. Thus, this plan proposes: (i) obtaining reduced graphene oxide; (ii) functionalization of this material with amino acids such as cysteine ¿¿and ethylenediamine amine derivative; (iii) evaluating the catalytic effect of the nanocatalyst (iv) evaluate the effect on the adsorption of contaminants. (AU)