CuO Nanoplatelets with Highly Dispersed Ce-Doping Derived from Intercalated Layered Double Hydroxides for Synergistically Enhanced Oxygen Reduction Reaction in Al–Air Batteries

Abstract

Development of highly efficient, low-cost, and durable electrocatalysts for the oxygen reduction reaction (ORR) is still a major obstacle that is preventing widespread commercialization of Al−air batteries. Herein, a cost-effective CuCe-layered double hydroxide (CuCe-LDH) was synthesized using a facile and scalable method of separate nucleation/growth steps, followed by an anion exchange process. The CuCe-LDH was successfully used as a precursor for the mass production of Ce-doped CuO nanoplatelets (Cu−Ce−O) as a Pt-free efficient electrocatalyst, which exhibited not only comparable electrocatalytic activity and durability in the ORR test but also a higher discharge voltage plateau when used in Al−air batteries compared to the benchmark Pt/C catalysts. A combination of structural characterizations and electrochemical analyses showed that the high ORR activity of the Cu−Ce−O catalyst was attributed to its high content of active species combined with their synergetic interactions. These results may provide an option for cost-effective production of ORR electrocatalysts at a large scale for practical applications of Al−air cathodes.

Confinement Synthesis Based on Layered Double Hydroxides: A New Strategy to Construct Single‐Atom‐Containing Integrated Electrodes

“…The Tafel slopes obtained from the LSV curves (Figure 3c) further demonstrate that SAC(PA+MA) had good ORR kinetics with a low Tafel slope of 59 mV dec −1 (η L ; where the overall ORR rate was determined by the surface reaction rate on the catalyst) and a high Tafel slope of 133 mV dec −1 (η H ; where the overall ORR rate is dependent on oxygen diffusion). [ 18 ] Notably, this slope was lower than those for SAC(PA) (η L = 102 mV dec −1 ; η H = 174 mV dec −1 ), SAC(MA) (η L = 64 mV dec −1 ; η H = 146 mV dec −1 ), and Pt/C (η L = 123 mV dec −1 ; η H = 246 mV dec −1 ). Moreover, the SAC(PA+MA) sample had a high electron transfer number (>3.8) and a low HO 2− yield (<10%) calculated on the basis of the RDE and rotation ring‐disk electrode curves (Figure S11, Supporting Information).…”

Co(II) or Cu(II) Schiff Base Complex Immobilized onto Carbon Nanotubes as a Synergistic Catalyst for the Oxygen Reduction Reaction

“…Besides Fe and Co doped hybrid materials, Ce‐doped CuO nanoplatelets also showed comparable electrocatalytic activity and durability in the ORR to the benchmark Pt/C catalyst . In addition, silver supported on nitrogen‐doped carbon sheets (Ag/NC) showed higher activity than NC in terms of onset potential and half‐wave potential .…”

Elucidating the Role of Oxide–Oxide/Carbon Interfaces of CuOx–CeO2/C in Boosting Electrocatalytic Performance

“…The two main reactions involved in such energy conversion/storage devices are the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), due to which O 2 electrochemistry is of tremendous interest to researchers . The slow kinetics, large overpotential, and complex mechanism due to the multielectron transfer of ORR/OER finally reduce the activity of such energy devices for practical utility . Pt and Pt-based materials , are still considered as the state-of-the-art electrocatalysts (ECs) for ORR, while RuO 2 and IrO 2 , are pre-eminent benchmarks for OER.…”

“…6 The slow kinetics, large overpotential, and complex mechanism due to the multielectron transfer of ORR/OER finally reduce the activity of such energy devices for practical utility. 7 Pt and Pt-based materials 8,9 are still considered as the state-of-the-art electrocatalysts (ECs) for ORR, while RuO 2 and IrO 2 10,11 are pre-eminent benchmarks for OER. However, these benchmark ECs suffer from drawbacks like dissolution during the reaction, lack of stability in both acidic and basic electrolytes, and scarcity, along with the high price.…”