Fe, Cu‐Coordinated ZIF‐Derived Carbon Framework for Efficient Oxygen Reduction Reaction and Zinc–Air Batteries

Abstract

Zeolitic imidazole frameworks (ZIFs) offer rich platforms for rational design and construction of high-performance nonprecious-metal oxygen reduction reaction (ORR) catalysts owing to their flexibility, hierarchical porous structures, and high surface area. Herein, an Fe, Cu-coordinated ZIF-derived carbon framework (Cu@Fe-N-C) with a well-defined morphology of truncated rhombic dodecahedron is facilely prepared by introducing Fe 2+ and Cu 2+ during the growth of ZIF-8, followed by pyrolysis. The obtained Cu@Fe-N-C, with bimetallic active sites, large surface area, high nitrogen doping level, and conductive carbon frameworks, exhibits excellent ORR performance. It displays 50 mV higher half-wave potential (0.892 V) than that of Pt catalysts in an alkaline medium and comparable performance to Pt catalysts in an acidic medium. In addition, it also has excellent durability and methanol resistance ability in both acidic and alkaline solutions, which makes it one of the best Pt-free catalysts reported to date for ORR. Impressively, when being employed as a cathode catalyst in zinc-air batteries, Cu@Fe-N-C presents a higher peak power density of 92 mW cm −2 than that of Pt/C (74 mW cm −2 ) as well as excellent durability.

Mixed Copper/Copper‐Oxide Anchored Mesoporous Fullerene Nanohybrids as Superior Electrocatalysts toward Oxygen Reduction Reaction

“…Importantly, the reported Cu‐carbon based nanomaterials, not only contain Cu and carbon but also other codopants such as nitrogen, phosphorous, and cobalt. Previous studies on the ORR electrocatalysts shown in Table , inform that the Cu moieties (mostly as 2+ or + ions) are coordinated or chemically linked to the codopants (nitrogen or phosphorous) to result in multiple centered (Cu‐N‐C or Cu‐P‐C) structures and the Cu contents were limited such as 0.7%, 1.01% . Hence, our results are unique in the sense that the electrocatalysts synthesized in this work contain mainly Cu species without involving in chemical linking and MFC 60 exists as the support matrix for Cu species.…”

“…State‐of‐the‐art ORR electrocatalyst studies have been reported on the development of catalysts utilizing Cu nanostructures into various forms of carbon such as nitrogen‐doped onion‐like graphite nanoshells, n‐doped carbon shells, pyrolytic nitrogen doped carbon, nitrogen codoped graphene, nitrogen doped hierarchical porous carbon, phosphorous doped hierarchically porous carbon, Ketjenblack carbon, zeolitic imidazole derived carbon frame work, and N‐enriched mesoporous carbon . Despite the different synthetic approaches and forms of nanocarbons utilized for the incorporation of Cu NPs, the ORR activity of these catalysts have been attributed to the chemical state of Cu (interior), Cu (surface), and Cu (edge), synergistic contribution from pyridinic N, the hierarchical porous structure and enhanced electrical conductivity tuned by the dopants, higher density of the Cu@Px active sites, facilitation of charge transfer from the inner Cu NPs to the outer N‐doped C shells and favorable electronic interactions with adsorbates in the ORR .…”

Designing a bioinspired synthetic tree by unidirectional freezing for simultaneous solar steam generation and salt collection

“…N 2 adsorption/desorption isotherms were used to characterize the porosity of the PVA‐based synthetic tree (Figure 2F). The sample had a Type III isotherm with no obvious saturated adsorption platform, indicating that the pore size distribution (inset) was irregular 35 . PPy particle with a diameter approximately 400 nm were successfully deposited on the surface of the PVA matrix as shown in Figure 2E and Figure S2.…”

2D Metal–Organic Framework Derived CuCo Alloy Nanoparticles Encapsulated by Nitrogen‐Doped Carbonaceous Nanoleaves for Efficient Bifunctional Oxygen Electrocatalyst and Zinc–Air Batteries

“…[11,[67][68][69][70][71][72][73] Recently,Z heng and co-workers re-portedC u,Co@NC derivedf rom ZIF-67 and Cu(OH) 2 .I nstead of CuCo alloy nanoparticles,t he Cu and Co nanoparticles were separately but homogeneously distributed in NC framework. [75] To date, it is still difficult to prepareaCu-based bimetallic alloy@NC based electrocatalysts for both ORR and OER. Fe was homogeneously distributed throughout the entire architecture, whereas Cu was distributed in the form of dispersed nanoparticles throughout the NC nanoparticles.…”