Engineering rhodium encapsulated indium doped fullerene for NH3, NO, and NO2 sensing

Nitrogenous gas pollutants, such as NH₃, NO, and NO₂, contribute significantly to environmental degradation, driving water pollution, biodiversity loss, and impaired air quality while posing critical risks to human health. Despite advancements in gas sensing technologies, materials with enhanced sensitivity and selectivity remain crucial for reliable pollutant detection. In this work, we investigate the gas sensing properties of rhodium-encapsulated indium-doped carbon-based fullerene (In-Rh@C₆₀) via DFT/PW6B95-D3/GenECP and ωB97X-D/LANL2DZ computational methods. The energy gap values were found to range from 0.705 to 1.537 eV and 3.980 to 5.166 eV for the respective methods. Upon adsorption of NH₃, NO, and NO₂, the energy gap decreases, indicating enhanced sensitivity. The observed chemisorption phenomena exhibit adsorption energies between -13.49 and -8.397 eV. Notably, adsorption of NO at the O-site and N-site leads to the most pronounced energy gap reductions (-0.515 eV and -0.389 eV). The green regions observed in the 3D non-covalent interaction plots signify strong van der Waals interactions, contributing to the stability of the adsorbent-adsorbate systems. This tailored system demonstrates suitability as an adsorbent material for gas pollutants, with adsorption site specificity taken into account. The findings suggest that the modified In-Rh@C₆₀ system holds potential as an adsorbent material for integration into sensor devices aimed at detecting NH₃, NO, and NO₂ gas pollutants.