Superlattices formed by interaction of hydrogen bromide and hydrogen chloride with Pt(111) and Pt(100) studied by LEED, Auger and thermal desorption mass spectroscopy

Garwood, Gerald A.; Hubbard, Arthur T.

doi:10.1016/0039-6028(81)90376-9

Cited by 56 publications

(27 citation statements)

References 45 publications

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“…Combining Eqs. (6) and (9) and neglecting the effect of chloride adsorption on Q 1 we can express the measured charge number l in terms of:…”

Section: Charge Numbers Per Adsorbed Anionmentioning

confidence: 99%

“…In situ surface scattering techniques [6], the CO displacement method [7] and a combination of cyclic voltammetry and ex situ techniques such as Auger electron spectroscopy (AES) and low energy electron diffraction (LEED) [8,9] have been employed to study chloride adsorption at a Pt(1 1 1) electrode surface. There is a significant amount of information concerning adsorption of chlorine [10][11][12] and HCl [13] or MgCl 2 [14] at Pt single crystal surfaces under UHV conditions.…”

Section: Introductionmentioning

confidence: 99%

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Thermodynamic studies of chloride adsorption at the Pt(111) electrode surface from 0.1 M HClO4 solution

Garcı́a-Aráez

Climent

Herrero

et al. 2005

Journal of Electroanalytical Chemistry

101

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“…Combining Eqs. (6) and (9) and neglecting the effect of chloride adsorption on Q 1 we can express the measured charge number l in terms of:…”

Section: Charge Numbers Per Adsorbed Anionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Thermodynamic studies of chloride adsorption at the Pt(111) electrode surface from 0.1 M HClO4 solution

Garcı́a-Aráez

Climent

Herrero

et al. 2005

Journal of Electroanalytical Chemistry

101

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“…Bromide adsorption on Pt(111) was subject of investigation by Hubbard’s group − providing precious information about the characterization of the formed adlayers. UHV measurements by LEED and Auger spectroscopy were employed to characterize the adlayer, and these works opened the way for further similar investigations. ,− The Pt(111)-Br ads adlayer was also characterized by STM , and surface X-ray scattering .…”

Section: Introductionmentioning

confidence: 99%

Bromide Adsorption on Pt(111) over a Wide Range of pH: Cyclic Voltammetry and CO Displacement Experiments

et al. 2018

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Bromide adsorption on Pt (111) is investigated by means of cyclic voltammetry and CO displacement experiments at different pH values. In acidic pH bromide adsorption is strongly overlapped with hydrogen desorption process. However, as the pH increases, hydrogen adsorption process displaces towards negative potentials while bromide adsorption remains nearly in the same potential region. In consequence, both processes decouple at higher pH values. The structural transition from Pt(111)-(1×1) to Pt(111)(3×3)-4Br is pH independent, in the SHE scale, and not observed for pH > 9.1. Values of pztc are extracted from the combination of voltammetric and CO displacedcharges. An alternative approach to obtain charge curves is based on the coincidence of the curves the structural transition characteristic of the bromide adlayer completion.Pztc values obtained from different approaches with and without bromide are compared and their dependence on pH discussed. A thermodynamic analysis is carried out to obtain hydrogen Gibbs excess and charge number from the Esin Markov analysis.or "commensurate" depending on what type of interaction is stronger, as pointed out by Lucas et al. 15 On the one hand, if the interaction between nearby adatoms is stronger, the structural adlayer will be "incommensurate". On the other hand, if the adatomsubstrate interaction is stronger, then structural adlayer will be "commensurate".Bromide adsorption on Pt(111) was subject of investigation by Hubbard's group [16][17][18] providing precious information about the characterization of the formed adlayers.UHV measurements by LEED and Auger spectroscopy were employed to characterize the adlayer, and these works opened the way for further similar investigations. 3,19-22 The Pt(111)-Br ads adlayer was also characterized by STM 3,23 and surface X-ray scattering. 19 The bromide adlayers can be formed either from bromide solutions or bromide vapors. 3 A structural transition at 0.25 V vs. RHE in 0.1 M HClO 4 was observed. 3,18,23 It was first proposed that this feature corresponds to the change from a Pt(111)-(3×3)-4Br adlattice at high potentials to a Pt(111)-(4×4)-7Br adlattice at low potentials, 18 but Itaya et al. observed an incommensurate Pt(111)-(1×1) structure instead of Pt(111)-(4×4)-7Br. 23 Independently of the technique used for the characterization of the Pt(111)-Br ads adlayer, it was shown that the Pt(111)-(3×3)-4Br structure is dense and the bromine adatoms are arranged in a closed-packed hexagonal layer, where the Br-Br distance is close to van der Waals diameter of bromine. They pointed out also that these adlayers are ordered preferentially along the directions of the substrate densest rows. 3,[16][17][18]24 Lucas et al. 19 proposed similar observations, although in these studies they observed that the (3×3) adlayer structure was incommensurate, whereas Orts et al. 3 proposed it as commensurate.In the present work, the knowledge about bromide adsorption on Pt(111) is extended by performing cyclic voltammetry and CO displacement experiments...

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“…23 Bromide adsorption on Pt(111) has been the object of study in several works using UHV measurements and in-situ electrochemical investigations. [24][25][26][27][28][29][30][31][32][33] The most characteristic feature is the structural transition from a Pt(111)-(3 × 3)-4Br adlattice at high potentials to a Pt(111)-(1 × 1) at low potentials, which is reflected in cyclic voltammetry experiments by a pH-independent sharp peak at 0.185 V vs. SHE. 27,32,34 A recent work in phosphate buffer solutions with different pH shows that the relative strength of bromide adsorption in comparison with OH adsorption becomes weaker as the pH is increased and that pH ca.…”

mentioning

confidence: 99%

Understandings on the Inhibition of Oxygen Reduction Reaction by Bromide Adsorption on Pt(111) Electrodes at Different pH Values

Briega-Martos¹,

Mello²,

Arán‐Ais³

et al. 2018

J. Electrochem. Soc.

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Oxygen reduction reaction (ORR) is studied on Pt(111) in the presence of different concentrations of bromide anions at different pH values ranging from very acidic to neutral solutions. While adsorbed bromide inhibits the ORR, the strength of the inhibition decreases when the pH is increased. This is a consequence of the lower relative adsorption energy of bromide at higher pH values, caused by the lower absolute applied potential. This is reflected in a shift of the onset of the ORR (as measured with the hanging meniscus rotating disc electrode, HMRDE) to higher values as the pH is increased. HMRDE measurements reveal that the limiting current density (j lim) coincides with the theoretical value for two electrons only at very acidic solutions. However, when pH is increased, j lim tends toward the value for a four electrons reaction. From pH > 3 j lim coincides both in the presence and in the absence of bromide despite the specific anion adsorption. Experiments in solutions with different ionic strength and hydrogen peroxide reduction measurements suggest that the formation of a reaction intermediate different from H 2 O 2 is favored at neutral pH values.

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Superlattices formed by interaction of hydrogen bromide and hydrogen chloride with Pt(111) and Pt(100) studied by LEED, Auger and thermal desorption mass spectroscopy

Cited by 56 publications

References 45 publications

Thermodynamic studies of chloride adsorption at the Pt(111) electrode surface from 0.1 M HClO4 solution

Thermodynamic studies of chloride adsorption at the Pt(111) electrode surface from 0.1 M HClO4 solution

Bromide Adsorption on Pt(111) over a Wide Range of pH: Cyclic Voltammetry and CO Displacement Experiments

Understandings on the Inhibition of Oxygen Reduction Reaction by Bromide Adsorption on Pt(111) Electrodes at Different pH Values

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