Ambipolar Enhanced Oxygen Evolution Reaction in Flexible van der Waals LaNiO₃ Membrane

Abstract

The atomic-level catalysis mechanism of various electrochemical processes can be achieved via the perovskite transition metal oxide (TMO) thin film with accurate stoichiometry and lattice ordering, which boosts the design and engineering of further promising catalysts. In the oxygen evolution reaction (OER), owing to the correlation nature of the TMO, strain can effectively tune the OER performance by modulating the electron occupancy and strengthening the exchange/coupling. However, the surface strain condition declines along with the rapid release of the interfacial lattice mismatch in conventional rigid TMO thin film. This not only restricts obtaining the most prominent strain tunability toward OER but also hinders understanding the fundamental mechanism. Here in this study, we have employed a van der Waals LaNiO 3 (LNO) membrane to determine the in situ strain effect on OER performance. We found that the OER activity is dramatically improved with both compressive and tensile strains exhibiting an ambipolar trend. Under only 0.2% compressive and tensile strains, the current densities are, respectively, enhanced ∼121% and ∼92% at 400 mV overpotential, compared with the unstrained LNO scenario. The weakened Ni−O chemisorption and enhanced charge transfer of LNO under varied strain conditions are responsible for this OER enhancement.

Recent advances in interface engineering strategy for highly‐efficient electrocatalytic water splitting

“…Consequently, the electrocatalytic performance is significantly enhanced. 151,152 For tensile strain, the increase in the interatomic distances of the late transition metals and early transition metals at the heterointerface can cause the d-band center to shift up and down, respectively. 153 Importantly, the upward shift of the d-band center increases the antibonding state energy in the catalyst-adsorbate system (Figure 13A) and reduces the antibonding state filling, which in turn enhances the interaction between the catalyst and the reactants (or reaction intermediates).…”

“…These strains modulate the d‐bandwidth of the material by affecting the overlap degree of the wave function, optimizing the adsorption capacity of the catalytic site for reaction intermediates. Consequently, the electrocatalytic performance is significantly enhanced 151,152 . For tensile strain, the increase in the interatomic distances of the late transition metals and early transition metals at the heterointerface can cause the d‐band center to shift up and down, respectively 153 .…”

Freestanding complex-oxide membranes

“…The new tools described in this review to produce freestanding complex-oxide membranes would enable: (a) Increasing the surface-to-volume ratio by (e.g. by using rolled-up nanomembrane tubes [56,95], (b) Accessing extreme-strain states where theory predicts increasing favorability of surface oxygen dissociation [256] but are not accessible in epitaxial heterostructures, (c) Actively tuning the catalytic activity via mechanical actuation [257], (d) Using mechanical detection methods to identify strains associated with catalytic processes [258], (e) Fabricating electrocatalytic cells to characterize the atomic and electronic structure of metal-oxide compounds interfaced with gases and liquids, using ambient pressure conditions (figure 8(c)) [259,260].…”

Magnetic Field‐Enhanced Electrocatalytic Oxygen Evolution on a Mixed‐Valent Cobalt‐Modulated LaCoO3 Catalyst

“…[28,29] Lanthanum cobaltate (LaCoO 3 , LCO) is a typical and representative perovskite cobalt oxide with the general formulation of ABO 3 , which has received the most attention in electrocatalytic OER due to its simple preparation process, distinctive electrical, structural, magnetic and catalytic characteristics. [30][31][32][33] However, the electrocatalytic activity of LCO is severely restricted, which is the result of the dissatisfactory adsorption of oxygen-containing intermediate due to inappropriate spin configuration of Co ions. [34] Previous work demonstrated that more than one A-site and/or B-site cation can be admitted into the perovskite structure since it possessed the admirable tolerance of lattice heterogeneity and mismatch between different metal (A/B)À O bond lengths.…”