The impact of platinum modification on the characteristics and optoelectronic properties of ordered mesoporous Titania

In this work, we report on the structural and morphological modifications, and their subsequent influence on the optoelectronic properties of platinum modified ordered mesoporous platinum-doped Titania (Pt-OMT). We found that higher Pt contents (>1 %Pt) lead to the destruction of the ordered structure and thus exhibit complex electrical conductivity behavior, which is intrigued by the grain boundary approximation model. The comprehensive investigation of temperature dependent resistance measurements (R-T curves) indicates a robust response to various gas environments and strong relationship between resistance, temperature and intergranular potential barrier eVs. The samples showed low eVs values in without gas (eVs∼0.26–0.45 eV) and nitrogen environment (eVs∼0.30–0.45 eV), while higher (eVs∼0.33–0.57 eV) values in the oxygen environment. Interpreting the adsorption mechanism relies on the eVs values in the oxygen environment, as well as the optical band gap, resistance values, and structural changes. This exploration provides a basis that researchers can extend to other ordered mesoporous metal oxides, paving the way for enhanced gas sensors and beyond.