Characterization of photocatalytic TiO₂ powder under varied environments using near ambient pressure X-ray photoelectron spectroscopy.

ABSTRACT: Consecutive eight study phases under the successive presence and absence of UV irradiation, water vapor, and oxygen were conducted to characterize surface changes in the photocatalytic TiO₂ powder using near-ambient-pressure X-ray photoelectron spectroscopy (XPS). Both Ti 2p and O 1s spectra show hysteresis through the experimental course. Under all the study environments, the bridging hydroxyl (OH_br) and terminal hydroxyl (OH_t) are identified at 1.1-1.3 eV and 2.1-2.3 eV above lattice oxygen, respectively. This enables novel and complementary approach to characterize reactivity of TiO₂ powder. The dynamic behavior of surface-bound water molecules under each study environment is identified, while maintaining a constant distance of 1.3 eV from the

SUBMITTER: Krishnan P 

PROVIDER: S-EPMC5327435 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature