Photoassisted reduction of sulfur dioxide in nonaqueous solutions at p-type semiconductor electrodes

Journal Article · Wed May 25 04:00:00 EDT 1983 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic00153a015· OSTI ID:5750931

Calabrese, G S; Sobieralski, T J; Wrighton, M S

The electrochemical behavior of SO/sub 2/ has been investigated at illuminated (632.8 and 514.5 nm) p-type semiconducting silicon (Si) tungsten sulfide (WS/sub 2/), and indium phosphide (InP) in (tetra-n-butyl ammonium perchlorate n-Bu/sub 4/N)C1O/sub 4/ solutions. SO/sub 2/ is photoreducible at each of these materials to form S/sub 2/O/sub 4//sup 2 -/, but the electrical power savings efficiencies are variable. The best power savings efficiency, approx. 11% at 514.5 nm (100 mW/cm/sup 2/), is obtained with a p-type InP photocathode modified by photoelectrodeposition of approx. 5 x 10/sup -8/ mol/cm/sup 2/ of Pt onto the surface. Naked p-InP is considerably less efficient, owing to poor kinetics for the reduction of SO/sub 2/. The deposition of platinum (Pt) onto p-InP forms neither a uniform ohmic contract nor a Schottky barrier; rather, studies of platinized n-InP show directly that the Pt serves as a catalyst for SO/sub 2/ reduction. Power savings efficiencies for p-type WS/sub 2/ and textured Si are low, owing to small output voltages. Preparative, controlled-potential photoelectrochemical reduction of SO/sub 2/ at all three photoelectrodes and Pt in CH/sub 3/CN/0.1 M SO/sub 2//0.5 M (n-Bu/sub 4/N)ClO/sub 4/ has been demonstrated to give > 90% current efficiency for formation of S/sub 2/O/sub 4//sup 2 -/, which can be precipitated and collected as Na/sub 2/S/sub 2/O/sub 4/.

• OSTI ID: 5750931
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 22:11; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400400 -- Electrochemistry
400500 -- Photochemistry
ACETONITRILE
ALKANES
AMMONIUM COMPOUNDS
AMMONIUM PERCHLORATES
CATALYTIC EFFECTS
CATHODES
CHALCOGENIDES
CHEMICAL REACTIONS
CHLORINE COMPOUNDS
DATA
ELECTRODES
ELEMENTS
EXPERIMENTAL DATA
HALOGEN COMPOUNDS
HYDROCARBONS
INDIUM COMPOUNDS
INDIUM PHOSPHIDES
INFORMATION
METALS
NITRILES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PERCHLORATES
PHOSPHIDES
PHOSPHORUS COMPOUNDS
PHOTOCATHODES
PLATINUM
PLATINUM METALS
PNICTIDES
REDUCTION
SEMIMETALS
SILICON
SULFIDES
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
THIOSULFATES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN COMPOUNDS
TUNGSTEN SULFIDES
VOLTAMETRY