Adsorption and desorption of acetone by TiO2 clusters: Transition state theory and sensing analysis

TiO2 cluster sensitivity to acetone adsorption using transition state theory is investigated. Ti10O20 cluster is used to perform the calculations using density functional theory with dispersion corrections. Adsorption state and transition state are calculated via thermodynamic energies, i.e., Gibbs free energy of adsorption and activation. Reaction rate, response, response time, and recovery time as a function of temperature and acetone concentration are calculated. Acetone burning in the air due to autoignition is considered using a logistic function. The results of the theory are compared with available experimental findings that revealed the quality of both theoretical and experimental results. The response time decreases with respect to acetone concentration. On the other hand, the recovery time in the desorption phase increases with acetone concentration. The temperature of maximum response is 356 °C, while the maximum response value is 2.9.