Exploring the potential of Bi2S3 nanoribbons in low temperature NO2 sensing: Experimental and theoretical insights by DFT studies

• A facile hydrothermal synthesis approach for 1D Bi 2 S 3 nanoribbons (NRBs). • 1D Bi 2 S 3 NRBs sensor shows selectivity towards NO 2 gas at 30 °C. • 1D Bi 2 S 3 NRBs sensor is capable of detecting trace-levels of 500 ppb NO 2 at 30 °C. • DFT studies explored interactions between Bi 2 S 3 NRBs and NO 2 , focusing on binding energies and charge transfer mechanisms. • DFT studies revealed that NO 2 interacts with the Bi 2 S 3 NRBs sensor surface via physisorption, primarily driven by charge transfer. In this study, one-dimensional (1D) bismuth sulfide nanoribbons (Bi 2 S 3 NRBs) were synthesized using a simple hydrothermal method and evaluated for room temperature gas sensing applications. Comprehensive characterization of 1D Bi 2 S 3 NRBs confirmed their high crystallinity, orthorhombic structure, and unique morphology, consisting of horizontally aligned, strip-like structures that resemble NRBs with lengths exceeding 10 µm, and a specific surface area of ∼51 m 2 /g. These structural features make Bi 2 S 3 NRBs highly suitable for gas sensing, offering enhanced surface interactions. When utilized as gas sensing materials, the Bi 2 S 3 NRBs demonstrated selectivity for nitrogen dioxide (NO 2 ) at room temperature, with a detection range from 500 ppb to 100 ppm. The sensor achieved a maximum response of 4.50 to 100 ppm NO 2 and a detection limit as low as 500 ppb. Density functional theory (DFT) calculations supported these experimental results, revealing that NO 2 molecules have a favorable adsorption energy on the Bi 2 S 3 surface compared to other gases. The sensing interaction was primarily governed by charge transfer during physisorption. Overall, these findings highlight the potential of Bi 2 S 3 NRBs as an effective room temperature NO 2 gas sensing materials, offering good selectivity, and low detection limits, supported by favorable surface interactions elucidated through DFT analysis.