Synthesis of Interface-Driven Tunable Bandgap Metal Oxides
Chemistry; Ames Laboratory; Microelectronics Research Center (MRC); Electrical and Computer Engineering; Materials Science and Engineering
Ames Laboratory, Chemistry, Materials Science and Engineering, Electrical and Computer Engineering, Microelectronics Research Center (MRC)
ACS Materials Letters
Mixed bandgap and bandgap tunability in semiconductors is critical in expanding their use. Composition alterations through single-crystal epitaxial growth and the formation of multilayer tandem structures are often employed to achieve mixed bandgaps, albeit with limited tunability. Herein, self-assembled one-dimensional coordination polymers provide facile synthons and templates for graphitic C-doped mesoporous oxides, gC-β-Ga2O3 or gC-In2O3 via controlled oxidative ligand ablation. These materials have mixed bandgaps and colors, depending on amount of gC present. The carbon/oxide interface leads to induced gap states, hence, a stoichiometrically tunable band structure. Structurally, a multiscale porous network percolating throughout the material is realized. The nature of the heat treatment and the top-down process allows for facile tunability and the formation of mixed bandgap metal oxides through controlled carbon deposition. As a proof of concept, gC-β-Ga2O3 was utilized as a photocatalyst for CO2 reduction, which demonstrated excellent conversion rates into CH4 and CO.
DOE Contract Number(s)
Iowa State University Digital Repository, Ames IA (United States)