title: Enzyme-assisted reforming of glucose to hydrogen in a photoelectrochemical cell.
abstract: Hydrogen gas has been produced by reforming glucose in a hybrid photoelectrochemical cell that couples a dye-sensitized nanoparticulate wide band gap semiconductor photoanode to the enzyme-based oxidation of glucose. A layer of porphyrin sensitizer is adsorbed to a TiO2 nanoparticulate aggregate sintered to a conducting glass substrate to form the photoanode. Excitation of the porphyrin results in electron injection into the TiO2, and migration to a microporous platinum cathode where hydrogen is produced by hydrogen ion reduction. The oxidized sensitizer dye is reduced by NADH, regenerating the dye and poising the NAD+/NADH redox couple oxidizing. The NAD+ is recycled to NADH by the enzyme glucose dehydrogenase, which obtains the necessary electrons from oxidation of glucose. The reforming of glucose produces gluconolactone, which hydrolyzes to gluconate; the electrochemical potential necessary to overcome thermodynamic and kinetic barriers to hydrogen production by NADH is provided by light. The quantum yield of hydrogen is approximately 2.5%.
authors.affiliation: Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-1604, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Hambourger
authors.forename: Alicia
authors.initials: A
authors.lastname: Brune
authors.forename: Devens
authors.initials: D
authors.lastname: Gust
authors.forename: Ana L
authors.initials: AL
authors.lastname: Moore
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Moore
mesh_terms: D004563:Electrochemistry; D005947:Glucose / Q000378:metabolism*; D042843:Glucose 1-Dehydrogenase / Q000378:metabolism*; D006859:Hydrogen; D008027:Light; D009243:NAD / Q000378:metabolism; D010777:Photochemistry
chemical_list: D009243:NAD; D006859:Hydrogen; D042843:Glucose 1-Dehydrogenase; D005947:Glucose