CoNi Nanoparticle-Decorated ZIF-67-Derived Hollow Carbon Cubes as a Bifunctional Electrocatalyst for Zn–Air Batteries

Abstract

CoNi nanoparticle-decorated hollow carbon cubes (CoNi-HCCs) were synthesized using ZIF-67 as a sacrificial template. The synthesis utilizes the thermal instability of ZIF-67, creating hollow carbon nanostructures while facilitating carbonization and introducing metal nanoparticles (e.g., CoNi). Prototype Zn–air batteries equipped with CoNi-HCCs exhibited a promising discharge potential of 1.21 V and a charge potential of 2.04 V at 20 mA cm–2. These values are superior to those of Pt–Ru, whose discharge and charge potentials were 1.20 and 2.08 V, respectively. CoNi-HCCs also displayed a high peak power density of 159.6 mW cm–2, which is significantly higher than the value for Pt–Ru (120.2 mW cm–2). After 90 h of bifunctional cycling at 10 mA cm–2, CoNi-HCCs only experienced an efficiency loss of 3.4% and maintained 55.3% battery efficiency, much more durable than Pt–Ru (41.7% after only 60 h).

Unveiling the unprecedented catalytic capability of micro-sized Co-ZIF-L for the thermal decomposition of RDX by 2D-structure-induced mechanism reversal

“…Synthesis and characterization of SL-Co-ZIF-L SL-Co-ZIF-L was rst synthesized by a straightforward aqueousphase reaction at room temperature. Similar to ZIF-67, which is widely used as a MOF-based catalyst or catalyst precursor in the areas of thermocatalysis, 35,36 photocatalysis 37,38 and electrocatalysis, [39][40][41] Co(NO 3 ) 2 $6H 2 O and 2-MI were chosen as the metal source and organic ligand, respectively. Nevertheless, deionized water was selected to substitute methanol for the dissolution of the two reactants.…”

Cobalt Nanoparticles Encapsulated with N-Doped Bamboo-Like Carbon Nanofibers as Bifunctional Catalysts for Oxygen Reduction/Evolution Reactions in a Wide pH Range

“…Recently, zeolitic imidazole frameworks with cobalt nodes (i.e., ZIF-67) are revealed as an ideal precursor for Co-based catalysts. They have a uniform distribution of Co-nodes, a high content of carbon and nitrogen, and adequate porosity, which led to homogeneously distributed N-doped sites and Co-containing sites, large surface area, and well-defined architecture. , …”

“…They have a uniform distribution of Co-nodes, a high content of carbon and nitrogen, and adequate porosity, which led to homogeneously distributed N-doped sites and Co-containing sites, large surface area, and well-defined architecture. 23,24 Most of the ZIF-67-derived catalysts employed the ZIF-67 precursor with a 3D polyhedron morphology, 25−27 while the 2D structure of ZIF-67 receives relatively less attention. 2D ZIF-67 (e.g., nanosheet and nanoleaves) has layered structures that enrich the accessible active sites and shorten the diffusion path for reactants and charges.…”

Efficient Low Temperature Performance of All Solid‐State Zinc‐Air Batteries with MnCo2O4/Carbon Fiber Bifunctional Electrocatalyst and Poly(Acrylic Acid) (PAA) Gel Polymer Electrolyte

“…Transition metal oxides (TMOs), carbonaceous materials like graphite and carbon nanotubes, and precious metals like Pt, Ir and Ru are the most important materials that have shown promising catalytic behavior towards ORR and/or OER. [8][9][10][11][12][13][14] The cost, scarcity, and instability (in terms of battery cycling performance) of precious metals have made their widespread use in ZABs impractical. [15] Although TMOs have proven to be active towards ORR/OER, their insulating nature is an issue for energy storage devices.…”

“…Carbon-based materials are used as conductive substrates for TMOs to improve charge transfer and conductivity issues. [5,10,14,[16][17][18] Carbon fibers have been shown to be excellent candidates for use in energy storage devices; they can be used as the conductive substrate for TMOs. Carbon fibers can be synthesized from various precursors like food scraps, polyaniline (PANI), and asphaltene.…”