Environmental Molecular Sciences Laboratory

About: Environmental Molecular Sciences Laboratory is a facility organization based out in Richland, Washington, United States. It is known for research contribution in the topics: Mass spectrometry & Ion. The organization has 1471 authors who have published 3010 publications receiving 169961 citations.

Nanovoid Incorporated IrxCu Metallic Aerogels for Oxygen Evolution Reaction Catalysis

Abstract: Ir-based nanomaterials are regarded as state-of-the-art cathode electrocatalysts in proton exchange membrane water electrolyzers (PEMWEs). Engineering the morphology of Ir-based three-dimensional architectures as electrocatalysts toward oxygen evolution reaction (OER) has been rarely studied. Here, we report the gelation of IrxCu metallic hydrogels self-assembled with ultrafine and nanovoid incorporated building blocks for enhancing the electrocatalytic performance toward OER. The composition-optimized Ir3Cu metallic aerogels exhibited improved catalytic activity and durability toward OER. The mesosized voids generated through the in situ galvanic replacement reaction and the macrosized porous systems make a great contribution to the increased number of active sites. First-principle calculations revealed the intrinsic optimized binding energy of Ir by alloying with Cu. The best catalytic performance necessities a balance of the adsorption and desorption energy. The well-defined morphology and enhanced OER...

Physisorption of CO on the MgO(100) Surface

Abstract: The ability to grow thin MgO(100) films of quality approaching that of vacuum-cleaved MgO(100) is demonstrated using low-energy electron diffraction and temperature-programmed desorption (TPD) of CO Highly ordered MgO(100) surfaces are used to study the adsorption and desorption of CO A linearly increasing sticking coefficient from 047 ± 003 to 090 is observed for relative CO coverages, θ, less than 08 monolayer (ML) For this coverage range, the total sticking coefficient is given by SMgO(1 − PCO) + SCOPCO, where SMgO (SCO) is the sticking on the bare (CO-covered) MgO and PCO is the probability of striking the CO-covered surface In TPD, the desorption of CO is dominated at very low coverages by desorption from sites influenced by defects At intermediate coverages (025−08 ML) the CO desorbs via first-order desorption At 08 ML where the monolayer peak saturates, the desorption energy is 17 ± 2 kJ/mol and the preexponential factor is 1 × 1015±2 s-1 The desorption energy increases linearly as co

Chemical Bonding between Cu and OxygenCopper Oxides vs O2 Complexes: A Study of CuOx (x = 0−6) Species by Anion Photoelectron Spectroscopy

Abstract: An extensive photoelectron spectroscopic study on the CuOx- (x = 0−6) species is presented. The photoelectron spectra of these species are obtained at four detachment photon energies: 2.33, 3.49, 4.66, and 6.42 eV. The spectra of the copper atom are included to show the dependence of the detachment cross sections on the photon energies. An intense two-electron transition to the 2P excited state of Cu is also observed in the 6.42 eV spectrum of Cu-. For CuO-, we observe an excited state of the anion, as well as photodetachment transitions to charge transfer excited states of CuO (Cu2+O2-). Six transitions are observed for CuO2- at 6.42 eV, revealing all six valence molecular orbitals of the linear OCuO molecule. CuO3- is observed to undergo photodissociation at 3.49 eV to give an internally hot CuO- plus O2. It is shown to have an OCuO2 type of structure, and its electronic structure can be viewed to be due to that of CuO perturbed by an O2. For CuO4-, two isomers are observed. One of them undergoes photo...