Diamond Publications - Search Results

Search Again...

These results only include publications that have been reviewed and processed by Diamond Light Source. To also view papers that have not yet been processed click here.

You can use the folder icon under Actions to collate papers as required. You can then click on View Folder in the left-hand navigation to review and/or download your folder.

One item found (0 items not approved).

Instruments / Technical Area	Publication Details	Published	Actions
B18-Core EXAFS	Correlating orbital composition and activity of LaMnxNi1–xO3 nanostructures toward oxygen electrocatalysis Mohammed A. Alkhalifah , Benjamin Howchen , Joseph Staddon , Veronica Celorrio , Devendra Tiwari , David J. Fermin Journal Of The American Chemical Society DOI: 10.1021/jacs.1c11757 Diamond Proposal Number(s): [10306] Show Abstract ▼ Abstract: The atomistic rationalization of the activity of transition metal oxides toward oxygen electrocatalysis is one of the most complex challenges in the field of electrochemical energy conversion. Transition metal oxides exhibit a wide range of structural and electronic properties, which are acutely dependent on composition and crystal structure. So far, identifying one or several properties of transition metal oxides as descriptors for oxygen electrocatalysis remains elusive. In this work, we performed a detailed experimental and computational study of LaMnxNi1–xO3 perovskite nanostructures, establishing an unprecedented correlation between electrocatalytic activity and orbital composition. The composition and structure of the single-phase rhombohedral oxide nanostructures are characterized by a variety of techniques, including X-ray diffraction, X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, and electron microscopy. Systematic electrochemical analysis of pseudocapacitive responses in the potential region relevant to oxygen electrocatalysis shows the evolution of Mn and Ni d-orbitals as a function of the perovskite composition. We rationalize these observations on the basis of electronic structure calculations employing DFT with HSE06 hybrid functional. Our analysis clearly shows a linear correlation between the OER kinetics and the integrated density of states (DOS) associated with Ni and Mn 3d states in the energy range relevant to operational conditions. In contrast, the ORR kinetics exhibits a second-order reaction with respect to the electron density in Mn and Ni 3d states. For the first time, our study identifies the relevant DOS dominating both reactions and the importance of understanding orbital occupancy under operational conditions.	Mar 2022

Instruments / Technical Area

Publication Details

Published

Actions

B18-Core EXAFS

Correlating orbital composition and activity of LaMnxNi1–xO3 nanostructures toward oxygen electrocatalysis

Mohammed A. Alkhalifah , Benjamin Howchen , Joseph Staddon , Veronica Celorrio , Devendra Tiwari , David J. Fermin

Journal Of The American Chemical Society

DOI: 10.1021/jacs.1c11757

Diamond Proposal Number(s): [10306]

Show Abstract ▼

Mar 2022