Single crystalline pyrochlore nanoparticles with metallic conduction as efficient bi-functional oxygen electrocatalysts for Zn–air batteries

Abstract

We have shown that highly efficient metallic pyrochlore oxide nanoparticles (Pb2Ru2O6.5) exhibit outstanding activity as bi-functional electrocatalysts in aqueous Zn–air batteries for ORR and OER.

Recent Advances in Materials and Design of Electrochemically Rechargeable Zinc–Air Batteries

“…c) Schematic illustrations of the synthesis of highly pure single crystalline pyrochlore oxide nanoparticles. Reproduced with permission . Copyright 2017, RSC.…”

CuCo2S4 Nanosheets@N‐Doped Carbon Nanofibers by Sulfurization at Room Temperature as Bifunctional Electrocatalysts in Flexible Quasi‐Solid‐State Zn–Air Batteries

“…The largely unsatisfactory performance in quasi-solid-state ZABs can be attributed to three main factors: i) limited catalytic activities arising from the sluggish ion/electron transport kinetic because of the relativity poor conductivity of BOs, especially in solid state electrolytes; ii) usage of polymer additives, such as polypyrrole [20] and polyimide (PI), [24] which are commonly employed to improve the flexibility of air electrodes, which however not only increase the "dead mass" for the electrodes and thus limit the energy density of the full devices, but also lead to the enlarged interfacial impedance with poor stability; iii) likely detachment of the weakly bound catalysts (BOs) from the N-doped carbon materials, which have been commonly prepared by physical mixed methods, such as ball milling and blending, and often occur at the frequent and large deformation conditions. The largely unsatisfactory performance in quasi-solid-state ZABs can be attributed to three main factors: i) limited catalytic activities arising from the sluggish ion/electron transport kinetic because of the relativity poor conductivity of BOs, especially in solid state electrolytes; ii) usage of polymer additives, such as polypyrrole [20] and polyimide (PI), [24] which are commonly employed to improve the flexibility of air electrodes, which however not only increase the "dead mass" for the electrodes and thus limit the energy density of the full devices, but also lead to the enlarged interfacial impedance with poor stability; iii) likely detachment of the weakly bound catalysts (BOs) from the N-doped carbon materials, which have been commonly prepared by physical mixed methods, such as ball milling and blending, and often occur at the frequent and large deformation conditions.…”

“…[1][2][3][4][5][6][7][8] In principle, the advancement of flexible ZABs is critically dependent on the availability of desired air electrodes with excellent bifunctional electrocatalysis for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), together with robust flexibility and mechanical strength. [19][20][21][22][23][24][25][26][27] For example, CuCo 2 O 4 quantum dots attached on N-doped carbon nanotubes (CuCo 2 O 4 @NCNTs) were shown to be an impressively bifunctional electrocatalyst including a good positive half-wave potential (0.80 V) for ORR and a low overpotential (467 mV@10 mA cm −2 ) for OER, which can contribute to an energy density of 659 W h kg −1 (in liquid state) for ZAB. Bimetallic oxides (BOs)@heteroatom-doped carbon hybrids have drawn considerable attentions, because of their high catalytic efficiency, derived from the synergetic effects between the nanostructured BOs (for OER) and N-doping in carbon materials (for ORR).…”

“…[9][10][11][12][13][14][15][16][17][18] For this purpose, several types of cathode materials have been explored. [23] Although great progress has been made recently with BOs@NC-based ZABs in liquid state, [19][20][21][22][23][24][25][26][27] the overall performances in quasi-solid-state are still far away from those key The performance of quasi-solid-state flexible zinc-air batteries (ZABs) is critically dependent on the advancement of air electrodes with outstanding bifunctional electrocatalysis for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), together with the desired mechanical flexibility and robustness. [19][20][21][22][23][24][25][26][27] For example, CuCo 2 O 4 quantum dots attached on N-doped carbon nanotubes (CuCo 2 O 4 @NCNTs) were shown to be an impressively bifunctional electrocatalyst including a good positive half-wave potential (0.80 V) for ORR and a low overpotential (467 mV@10 mA cm −2 ) for OER, which can contribute to an energy density of 659 W h kg −1 (in liquid state) for ZAB.…”

Fingerprint of local disorder in long range ordered isometric pyrochlores

“…: Li-ion battery 8,9 , photoluminescence 10,11 , laser materials 12 , solid oxide fuel cells 13,14 …). They possess exotic physical properties 15–18 exuding a strong interest in their modelling and simulation 19,20 .…”