Comparative theoretical study of Al- and Ga-doped T-graphene for enhanced NO sensing

The development of high-performance toxic gas sensors is critical for environmental monitoring and human health protection. In this study, we present a theoretical investigation into the efficacy of pristine and Al/Ga-doped T-graphene monolayers for nitric oxide (NO) detection. First-principles calculations reveal that pristine T-graphene exhibits limited reactivity and sensitivity toward NO, making it unsuitable for sensing applications. In contrast, Al- and Ga-doped T-graphene demonstrate markedly enhanced NO adsorption, with significantly higher binding energies and substantial electronic property modulations upon gas adsorption. Notably, Ga-doped T-graphene exhibits a strong adsorption energy of –19.20 kcal/mol and a negative Gibbs free energy (–8.39 kcal/mol), confirming spontaneous NO capture with a chemisorption nature. Furthermore, the ultra-fast recovery time (0.01 s) suggests excellent reversibility, positioning Ga-doped T-graphene as a highly promising candidate for practical NO sensing. These findings underscore the potential of doped T-graphene as an efficient, sensitive, and reusable material for next-generation gas sensors.