TY - JOUR

T1 - Engendering Unprecedented Activation of Oxygen Evolution via Rational Pinning of Ni Oxidation State in Prototypical Perovskite

T2 - Close Juxtaposition of Synthetic Approach and Theoretical Conception

AU - Pittkowski, Rebecca

AU - Divanis, Spyridon

AU - Klementova, Mariana

AU - Nebel, Roman

AU - Nikman, Shahin

AU - Hoster, Harry

AU - Mukerjee, Sanjeev

AU - Rossmeisl, Jan

AU - Krtil, Petr

PY - 2021/1/15

Y1 - 2021/1/15

N2 - Rational optimization of the OER activity of catalysts based on LaNiO3 oxide is achieved by maximizing the presence of trivalent Ni in the surface structure. DFT investigations of the LaNiO3 catalyst and surface structures related to it predict an improvement in the OER activity for these materials to levels comparable with the top of the OER volcano if the La content is minimized while the oxidation state of Ni is maintained. These theoretically predicted structures of high intrinsic OER activity can be prepared by a templated sprayfreeze freeze-drying synthesis followed by a simple postsynthesis exfoliation-like treatment in acidic media. These nanocrystalline LaNiO3-related materials confirm the theoretical predictions, showing a dramatic improvement in OER activity. The exfoliated surfaces remain stable in OER catalysis, as shown by an in-operando ICP-OES study. The unprecedented OER activation of the synthesized LaNiO3 based materials is related to a close juxtaposition of the theoretical conception of ideal structural motifs and the ability to engender such motifs using a unique synthetic procedure, both principally related to stabilization and pinning of the Ni oxidation state within the local coordination environment of the perovskite structure.

AB - Rational optimization of the OER activity of catalysts based on LaNiO3 oxide is achieved by maximizing the presence of trivalent Ni in the surface structure. DFT investigations of the LaNiO3 catalyst and surface structures related to it predict an improvement in the OER activity for these materials to levels comparable with the top of the OER volcano if the La content is minimized while the oxidation state of Ni is maintained. These theoretically predicted structures of high intrinsic OER activity can be prepared by a templated sprayfreeze freeze-drying synthesis followed by a simple postsynthesis exfoliation-like treatment in acidic media. These nanocrystalline LaNiO3-related materials confirm the theoretical predictions, showing a dramatic improvement in OER activity. The exfoliated surfaces remain stable in OER catalysis, as shown by an in-operando ICP-OES study. The unprecedented OER activation of the synthesized LaNiO3 based materials is related to a close juxtaposition of the theoretical conception of ideal structural motifs and the ability to engender such motifs using a unique synthetic procedure, both principally related to stabilization and pinning of the Ni oxidation state within the local coordination environment of the perovskite structure.

KW - electrocatalysis

KW - oxygen evolution

KW - rational catalyst design

KW - DFT

KW - ELECTROCATALYTIC ACTIVITY

KW - RECENT PROGRESS

KW - WATER

KW - ALKALINE

KW - LANIO3

KW - CATALYSTS

KW - NICKEL

KW - NANOCRYSTALS

KW - RUO2

KW - NANOPARTICLES

U2 - 10.1021/acscatal.0c04733

DO - 10.1021/acscatal.0c04733

M3 - Journal article

VL - 11

SP - 985

EP - 997

JO - ACS Catalysis

JF - ACS Catalysis

SN - 2155-5435

IS - 2

ER -