title: Enhanced Photocatalytic Activity of Bismuth Precursor by Rapid Phase and Surface Transformation Using Structure-Guided Combustion Waves.
abstract: The development of an efficient method for manipulating phase and surface transformations would facilitate the improvement of catalytic materials for use in a diverse range of applications. Herein, we present the first instance of a submicrosecond time frame direct phase and surface transformation of Bi(NO3)3 rods to nanoporous β-Bi2O3 rods via structure-guided combustion waves. Hybrid composites of the prepared Bi(NO3)3·H2O rods and organic fuel were fabricated by a facile preparation method. The anisotropic propagation of combustion waves along the interfacial boundaries of Bi(NO3)3·H2O rods induced direct phase transformation to β-Bi2O3 rods in the original structure due to the rapid pyrolysis, while the release of gas molecules enabled the formation of nanoporous structures on the surfaces of rods. The developed β-Bi2O3 rods showed improved photocatalytic activity for the photodegradation of rhodamine B in comparison with Bi(NO3)3·H2O rods and α-Bi2O3 rods due to the more suitable interdistance and the large contact areas of the porous surfaces. This new method of using structure-guided combustion waves for phase and surface transformation may contribute to the development of new catalysts as well as the precise manipulation of diverse micronanostructured materials.
authors.affiliation: School of Mechanical Engineering, Korea University (BK21+) , Seoul 136-701, Korea.
authors.forename: Kang Yeol
authors.initials: KY
authors.lastname: Lee
authors.affiliation: School of Mechanical Engineering, Korea University (BK21+) , Seoul 136-701, Korea.
authors.forename: Hayoung
authors.initials: H
authors.lastname: Hwang
authors.affiliation: Department of Chemistry and Research Institute of Natural Science, Gyeongsang National University , Jinju 660-701, Korea.
authors.forename: Tae Ho
authors.initials: TH
authors.lastname: Kim
authors.affiliation: School of Mechanical Engineering, Korea University (BK21+) , Seoul 136-701, Korea.
authors.forename: Wonjoon
authors.initials: W
authors.lastname: Choi
keywords: bismuth oxide; combustion waves; nanoporous surfaces; phase transformation; photocatalytic activity; thermopower waves