Volume 3, Issue 5, Pages 812-821 (November 2017) Spin-State Regulation of Perovskite Cobaltite to Realize Enhanced Oxygen Evolution Activity  Yun Tong, Yuqiao Guo, Pengzuo Chen, Haifeng Liu, Mengxing Zhang, Lidong Zhang, Wensheng Yan, Wangsheng Chu, Changzheng Wu, Yi Xie  Chem  Volume 3, Issue 5, Pages 812-821 (November 2017) DOI: 10.1016/j.chempr.2017.09.003 Copyright © 2017 Elsevier Inc. Terms and Conditions

Chem 2017 3, 812-821DOI: (10.1016/j.chempr.2017.09.003) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 1 Schematic Illustration and HRTEM Images of LCO Films Schematic illustration of the synthetic process (A) and high-resolution TEM images of as-prepared LCO (100) (B), LCO (110) (C), and LCO (111) (D) films. See also Table S1 and Figure S1. Chem 2017 3, 812-821DOI: (10.1016/j.chempr.2017.09.003) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 2 XRD Patterns, Elemental Mapping, and Magnetic and Elecronic Behaviors (A and B) θ/2θ symmetric (A) and ω-scan (B, rocking curve) XRD patterns for LCO (100), (110), and (111) films. See also Figures S2–S4. (C) The corresponding EDS spectrum and elemental mapping images of LCO (100) film. See also Figures S5 and S6. (D) Single cobalt magnetic moment depends on the magnetic field at the temperature of 10 K. See also Figure S10. (E) Average eg electrons of different oriented LCO films. (F) Temperature-dependent conductivity for three oriented LCO films. Chem 2017 3, 812-821DOI: (10.1016/j.chempr.2017.09.003) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 3 XANES Spectra and Schematic Illustration of IS State Transition (A and B) Co L-edge (A) and O K-edge (B) XANES spectra for LCO (100), (110), and (111) films. (C) Schematic illustration of the transition of electrons from t2g to eg orbital and the evolution of IS state. See also Figure S11. Chem 2017 3, 812-821DOI: (10.1016/j.chempr.2017.09.003) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 4 The Reaction Mechanism and DFT Caculation of Adsorption Free Energy (A) The reaction mechanism of LCO films during the OER process. (B–D) The OER free-energy diagrams of (B) LCO (100), (C) LCO (110), and (D) LCO (111) films for the OER process depending on the reaction coordinates. Chem 2017 3, 812-821DOI: (10.1016/j.chempr.2017.09.003) Copyright © 2017 Elsevier Inc. Terms and Conditions

Figure 5 OER Performance and the Relationship between OER Activity and Spin Configuration (A) The OER polarization curves of the LCO films. (B) The corresponding Tafel plots for LCO films. (C) Chronoamperometric response of differently oriented LCO films at the overpotential of 470 mV. (D) Direct comparison of the activity (solid line) and Tafel slope (dashed line) for as-obtained LCO films. (E) The relationship between OER activity and spin configuration (free energy, conductivity as well as eg electrons filling status) of differently oriented LCO films. Chem 2017 3, 812-821DOI: (10.1016/j.chempr.2017.09.003) Copyright © 2017 Elsevier Inc. Terms and Conditions