Ab initio computational modeling of the electrochemical reactivity of quinones on gold and glassy carbon electrodes

Quantum Simulations and Experimental Insights into Glyphosate Adsorption Using Graphene-Based Nanomaterials

The increasing global demand for food and agrarian development brings to light a dual issue concerning the use of substances that are crucial for increasing productivity yet can be harmful to human health and the environment when misused. Herein, we combine insights from high-level quantum simulations and experimental findings to elucidate the fundamental physicochemical mechanisms behind developing graphene-based nanomaterials for the adsorption of emerging contaminants, with a specific focus on pesticide glyphosate (GLY). We conducted a comprehensive theoretical and experimental investigation of graphene-based supports as promising candidates for detecting, sensing, capturing, and removing GLY applications. By combining ab initio molecular dynamics and density functional theory calculations, we explored several chemical environments encountered by GLY during its interaction with graphene-based substrates, including pristine and punctual defect regions. Our results unveiled distinct interaction behaviors: physisorption in pristine and doped graphene regions, chemisorption leading to molecular dissociation in vacancy-type defect regions, and complex transformations involving the capture of N and O atoms from impurity-adsorbed graphene, resulting in the formation of new GLY-derived compounds. The theoretical findings were substantiated by FTIR and Raman spectroscopy, which proposed a mechanism explaining GLY adsorption in graphene-based nanomaterials. The comprehensive evaluation of adsorption energies and associated properties provides valuable insights into the intricate nature of these interactions, shedding light on potential applications and guiding future experimental investigations of graphene-based nanofilters for water decontamination.

Electrochemiluminescence for Characterizing the Polymerization Process during Graphitic Carbon Nitride Synthesis

The physicochemical properties and application performances of graphitic carbon nitride (g‐CN) are highly dependent on its polymerization degree, thus a facile method for screening the polymerization degree is highly desired. Here, electrochemiluminescence (ECL) is creatively employed as an effective tool to achieve this goal. Extension of π‐system and change in pedant groups during g‐CN polymerization process are characterized by g‐CN nanosheets/dissolved oxygen (CNNS/O2) and Ru(bpy)32+/CNNS co‐reactant ECL systems, respectively. Linear intensity enhancement along with positive shift in the onset and peak potentials of cathodic CNNS/O2 ECL, as well as linear intensity decreasing in anodic Ru(bpy)32+/CNNS ECL, are observed during polymerization of dicyandiamide to g‐CN, suggesting the feasibility of ECL on studying the polymerization degree. The ECL method would provide a promising prospect for novel properties exploration and application performances optimization of g‐CN.