title: Nanoporous delafossite CuAlO2 from inorganic/polymer double gels: a desirable high-surface-area p-type transparent electrode material.
abstract: Nanoporous structures of a p-type semiconductor, delafossite CuAlO(2), with a high crystallinity have been fabricated through an inorganic/polymer double-gel process and characterized for the first time via Mott-Schottky measurements. The effect of the precursor concentration, calcination temperature, and atmosphere were examined to achieve high crystallinity and photoelectrochemical properties while maximizing the porosity. The optical properties of the nanoporous CuAlO(2) are in good agreement with the literature with an optical band gap of 3.9 eV, and the observed high electrical conductivity and hole concentrations conform to highly crystalline and well-sintered nanoparticles observed in the product. The Mott-Schottky plot from the electrochemical impedance spectroscopy studies indicates a flat-band potential of 0.49 V versus Ag/AgCl. It is concluded that CuAlO(2) exhibits band energies very close to those of NiO but with electrical properties very desirable in the fabrication of photoelectrochemical devices including dye-sensitized solar cells.
authors.affiliation: Department of Chemistry and Biochemistry, Arizona State University , Tempe, Arizona 85287-1604, United States.
authors.forename: Barun
authors.initials: B
authors.lastname: Das
authors.forename: Adèle
authors.initials: A
authors.lastname: Renaud
authors.forename: Alex M
authors.initials: AM
authors.lastname: Volosin
authors.forename: Lei
authors.initials: L
authors.lastname: Yu
authors.forename: Nathan
authors.initials: N
authors.lastname: Newman
authors.forename: Dong-Kyun
authors.initials: DK
authors.lastname: Seo
mesh_terms: D003460:Crystallization; D058266:Dielectric Spectroscopy; D004553:Electric Conductivity; D004566:Electrodes; D005782:Gels; D046529:Microscopy, Electron, Transmission; D058608:Nanopores / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D012666:Semiconductors; D013056:Spectrophotometry, Ultraviolet; D013499:Surface Properties
chemical_list: C574001:CuAlO(2); D005782:Gels; D010087:Oxides