Anodic oxide film on antimony: II. Parameters of film growth and dissolution kinetics in neutral and alkaline media

The photoelectrochemical behavior of GaSb has been investigated in aqueous NaOH, NaC1, and HC1 solutions. Despite the relatively narrow bandgap, the photo-oxidation and dissolution process dominated the behavior of n-GaSb at potentials positive of the flatband potential (V~). At high pH and sufficient solution agitation, the etch rate was proportional to light intensity. At potentials 0.5 V positive of Vn, a tunneling oxidation current developed resulting in an etch process that was independent of the light intensity. XPS analysis of the etched surface suggested that an increase in the dissolution rate of antimony oxides took place at high pH and solution agitation. The formation of an antimony oxide film resulted in surface passivation. Because of the relatively negative flatband potential of n-GaSb, oxygen was reduced at the same potential that n-GaSb was photo-oxidized. Thus, at the flatband potential, an open-circuit photoetch rate of 1 i~m/min was observed in an air-saturated solution.

Section: Xps Analysis--a Surface Science (Mountain View Ca)mentioning

confidence: 99%

Photoelectrochemical Etching of GaSb

Propst

Vogt

Kohl

1993

“…A proposed scheme for the processes represented by Peak II is Sb(HS)~ds ~ Sb(S)ads + H + + e- [3] Sb(S)ad~ + HS-~ HSbS2- [4] yielding a hydro-sulfo Sb complex as an intermediate. This complex could then either dissolve or participate in a rapid electron-transfer reaction resulting in bulk antimony sulfide film formation HSbS2-~-HSbS2 + e- [5] 2HSbS~ ~ Sb~S3 + H~S [6] A similar mechanism has been proposed for the anodic formation of an oxide film on antimony (20,21). It was re- ported that the current efficiency for oxide formation is nearly 100% in acidic media, whereas extensive metal dissolution occurs during oxidation in alkaline solutions.…”

Section: Resultsmentioning

confidence: 87%

“…HSbS2-~-HSbS2 + e- [5] 2HSbS~ ~ Sb~S3 + H~S [6] A similar mechanism has been proposed for the anodic formation of an oxide film on antimony (20,21). It was re- ported that the current efficiency for oxide formation is nearly 100% in acidic media, whereas extensive metal dissolution occurs during oxidation in alkaline solutions.…”

Section: Resultsmentioning

confidence: 94%

See 1 more Smart Citation

Formation and Reduction of Anodic Sulfide Films on Antimony Electrodes

Viehbeck

Hackerman

1984

The growth and reduction of anodic Sb2S3 films on antimony electrodes in alkaline sulfide solutions has been investigated using potentiodynamic, galvanostatic, and potentiostatic techniques. The sulfidation mechanism and the efficiency of charge storage in the sulfide film ave dependent on the electrode potential and current density. The initial stages of film formation follow a high field growth process involving ionic transport through the sulfide film. The growth of thicker films is controlled by coupled electrochemical and chemical reactions involving mass transport and nucleation. Metal dissolution accompanies film formation under most growth conditions. The anodic and cathodic behavior of these films is consistent with their rectification or n-type semiconductor properties. a mercury/mercuric sulfide (red) slurry in contact with ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 129.115.103.99 Downloaded on 2015-06-14 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 129.115.103.99 Downloaded on 2015-06-14 to IP

“…Unfortunately, the question cannot be answered unequivocally. Studies of the electrochemistry of antimony reported in the literature do not provide an answer (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27). Superposition of the cathodic polarization curves for tin (Fig.…”

Section: Discussionmentioning

confidence: 99%

The Effect of Antimony on the Corrosion of Tin in Deaerated Citric Acid

Leidheiser

Rauch

Ibrahim

et al. 1982

The purpose of these studies is to obtain a better understanding of the role which antimony plays in accelerating the corrosion of tin. Tin-antimony alloys were prepared by electrodeposition and the corrosion rates were determined from polarization data obtained in deaerated 0.33M citric acid. The corrosion rates were linearly related to the antimony concentration in the alloy and were described by the following equation Corrosion rate in A/m s = 0.0003 + 0.000079X whereX is the antimony concentration in the tin in ppm. A mechanism is proposed in which small amounts of antimony oxide on a tin substrate catalyze the hydrogen evolution reaction. Nitrite additions to deaerated citric acid greatly accelerated the corrosion rate of unalloyed tin. The effects of nitrite were described by the following equationwhere Y is the nitrite concentration in the citric acid in ppm. The nitrite results and the great effect of antimony on the corrosion rate were attributed to the fact that a partially oxidized surface serves as a remarkably effective catalyst for the hydrogen evo]ution reaction on tin.Seweral isolated studies have shown that antimony has an accelerating effect on the corrosion of tin in aqueous solutions (1, 2) and in the oxidation of metallic tin (3). A satisfying explanation of the effects of antimony has not been offered. It is also well known that nitrite and nitrate greatly accelerate the corrosion of tin (4-6). In the latter case there is a better understanding since it is well recognized that oxidizing species accelerate the cathodic reaction on tin. Much work has been done in understanding those factors that lead to increased tin corrosion under conditions simulating food storage in tinned containers (7-11). Albu-Yaron and Semel (12), for example, have emphasized the importance of nitrate in increasing the corrosion rate of containers for stored food products.The purpose of the research reported herein is to obtain a better understanding of the role that antimony plays in accelerating the corrosion of tin. Experiments were also carried out in nitrite solutions with the hope that experimental data with nitrite might assist in interpreting data obtained with antimony additions to tin. ExperimentalAll measurements were carried out in 0.33M citric acid prepared from CP reagent grade and distilled water. Tin rods, 9.5 mm in diameter, and antimony rods, 12.7 mm in diameter, were used as electrodes in polarization work. Both materials were supplied by Alfa Products. Tin-antimony alloys were prepared by electrodeposition on the tin rods with an apparent surface area of 5 cm 2. The plating bath contained Na2SnO8 9 3H20, 25 g/liter; and NaOH, 4 g/liter. Antimony additions to the plating bath were made from a solution of antimony chloride containing 1000 ppm antimony as determined by atomic absorption analysis. 9 Electrochemical Society Active Member.Plating conditions were 60~ stirred solution, 15(}-200 A/m 2, 3-4 hr. Plating baths containing low concentrations of antimony were prepared from a solution formed by dis...