Electron-redistributed Ni–Co oxide nanoarrays as an ORR/OER bifunctional catalyst for low overpotential and long lifespan Li–O₂ batteries

Abstract

Lithium-oxygen batteries with extra-high energy density attracted increasing attention. However, their development is limited by sluggish oxygen redox kinetics, resulting in large overpotential and low cyclic life. Herein, N-NiCoO2/CoO array...

Geometric and Electronic Engineering in Co/VN Nanoparticles to Boost Bifunctional Oxygen Electrocatalysis for Aqueous/Flexible Zn‐Air Batteries

“…At present, transition metal‐based materials (Co, [5] Ni, [6] Cu, [7] and Mn [8] ) for multiple electrochemical reactions have been inspired by a fast‐evolving research field due to the virtues of plentiful reserves and promising activity. Among them, Co features a similar d ‐electron configuration to Pt and thereby has a breathtaking affinity for oxygen‐containing intermediates, which is conducive to the elementary reaction in the oxygen‐catalyzed process [9] .…”

Designing Ag@NiO as Air Electrode Catalysts with Synergistic Interface and Doping Engineering Strategies for High-Performance Lithium–Oxygen Batteries

“…14 Unfortunately, due to the poor electronic conductivity and limited active sites of NiO, it usually leads to high overvoltage and poor cycle performance of Li−O 2 batteries. 15 A few recent studies have shown that heteroatom doping can tune the surface electronic structure in order to improve electronic conductivity and build interface defects to expose more active sites, which are beneficial for enhancing catalytic activity. 16,17 Noble metal catalysts (such as Pt, Au, Ag, etc.)…”

“…In particular, nickel oxide has many advantages, such as low cost, abundant resources, environment-friendliness, distinctive 3d electron number, extraordinary e g orbitals, and high electron transmission efficiency; hence, NiO catalysts have been considered as an ideal substitute for the ORR and OER process. , Wang et al successfully prepared the novel flower-like NiO as an air electrode catalyst for Li–O 2 batteries, which showed excellent ORR and OER catalytic activity in order to promote cycling performance . Unfortunately, due to the poor electronic conductivity and limited active sites of NiO, it usually leads to high overvoltage and poor cycle performance of Li–O 2 batteries . A few recent studies have shown that heteroatom doping can tune the surface electronic structure in order to improve electronic conductivity and build interface defects to expose more active sites, which are beneficial for enhancing catalytic activity. , Noble metal catalysts (such as Pt, Au, Ag, etc.)…”

Synergy of Carbon Nanotube-Supported Bimetallic Nanoalloy Catalysts in Rechargeable Lithium–Oxygen Batteries

“…In the OER process, the Co site may facilitate the transfer of the oxygenated species to the Pt site for activation and subsequent oxidation to molecular oxygen. 13,21,22 Co n /CNT catalysts were synthesized by a hydrothermal method in which the two metal precursor feeding ratio was controlled (e.g., 25, 50, and 75% Co). Briefly, 100 mg of CNTs was dispersed into 50 mL of DMF by sonicating for 0.5 h. Then, platinum acetylacetonate and cobalt acetylacetonate in a controlled molar ratio were added to the above suspension, followed by sonicating for another 0.5 h and stirring for 15 min.…”

“…The presence of Co and Pt atoms in a random surface alloy state could produce a bifunctional catalytic synergy in which the Pt site activates molecular oxygen whereas the Co site enables the removal or relocation of the intermediate −OLi species on the surface in the ORR process. In the OER process, the Co site may facilitate the transfer of the oxygenated species to the Pt site for activation and subsequent oxidation to molecular oxygen. ,, Despite the significant progress, a key problem in rechargeable Li–air batteries is the lack of understanding of how a solid catalyst catalyzes the formation and decomposition of solid Li 2 O 2 , especially the confronting passivation and loss of catalyst–Li 2 O 2 contact, in the discharging/charging processes. Recently, the structural change at the RuO 2 (catalyst)/Li 2 O 2 interface during discharging and charging is examined by an operando scanning transmission electron microscopy (STEM) study in a Li–O 2 microbattery .…”