Molecular adsorption behavior and photoelectric properties of SnO2 (221) crystal plane.

In this paper, the molecular adsorption behavior of the SnO 2 (221) crystal plane is simulated by density functional theory, and the photoelectric properties of the crystal plane are studied. Through theoretical simulation, H 2 O, O 2 , and N 2 molecules are located on three different adsorption active sites of the crystal plane. The individual adsorption of the three molecules reduces the conductivity of the crystal plane. The conductivity increases when the molecules are co-adsorbed. The characteristic adsorption species (CAS) of the crystal plane are H 2 O and O 2 molecules. This is consistent with the experimental results of electrochemical impedance spectroscopy (EIS). The O 2 molecule shifts the response peak of the photocurrent spectrum to a low wavelength. Understanding the CAS of the crystal plane and its influence on the optical and electrical properties of materials has enlightening significance for further analysis of the photoelectric behavior of materials, and is helpful to provide the theoretical and experimental basis for the controllable design and synthesis of gas-sensitive materials. [Display omitted] • The characteristic adsorption species of the SnO 2 (221) crystal plane are H 2 O and O 2 molecules. • H 2 O, O 2 , and N 2 molecules have different adsorption active sites. • The individual adsorption of the three molecules alone decreases the crystal plane conductivity, but the co-adsorption increases it. • The response peak of the photocurrent spectrum for O 2 molecule adsorption shifts to a lower wavelength. [ABSTRACT FROM AUTHOR]