The potential of Chitosan-gr-Polysulphanilic acid as a sensor for phenol detection has been thoroughly investigated using quantum mechanical calculations in both gas and aqueous phases. The results demonstrate that Chitosan-gr-Polysulphanilic acid exhibits high sensitivity and a strong affinity for phenol molecules. The adsorption energy of its most stable configuration is approximately − 14.69 kcal/mol in the gas phase and − 12.88 kcal/mol in the aqueous phase, indicating a favorable binding interaction. The adsorption of phenol significantly reduces the material's band gap, which enhances its electrical conductivity, suggesting that Chitosan-gr-Polysulphanilic acid could be an effective candidate for phenol detection, particularly in electronic sensor applications. The material’s electronic properties, including the HOMO and LUMO energy levels, also indicate that phenol adsorption leads to a substantial reduction in the band gap, which can be leveraged for more sensitive and efficient detection of phenol. Additionally, the interaction between Chitosan-gr-Polysulphanilic acid and phenol has been shown to induce a notable change in the material's work function, further supporting its potential for use as a work function-based sensor for phenol detection. The material's ability to alter its electronic properties upon adsorption of phenol highlights its potential as a responsive and adaptable sensing material. In terms of practical application, the desorption of phenol from Chitosan-gr-Polysulphanilic acid was found to be remarkably efficient, with a rapid recovery time of approximately 4.09 ms. This fast recovery time suggests that the material is highly suitable for real-time sensor applications, where quick adsorption and desorption cycles are essential for effective phenol monitoring. In conclusion, Chitosan-gr-Polysulphanilic acid shows significant promise as a phenol sensor, offering high sensitivity, rapid response times, and reversible adsorption-desorption behavior, making it an excellent candidate for environmental monitoring and industrial applications where phenol detection is critical.