Cu, Co‐Embedded N‐Enriched Mesoporous Carbon for Efficient Oxygen Reduction and Hydrogen Evolution Reactions

Abstract

Rational synthesis of hybrid, earth‐abundant materials with efficient electrocatalytic functionalities are critical for sustainable energy applications. Copper is theoretically proposed to exhibit high reduction capability close to Pt, but its high diffusion behavior at elevated fabrication temperatures limits its homogeneous incorporation with carbon. Here, a Cu, Co‐embedded nitrogen‐enriched mesoporous carbon framework (CuCo@NC) is developed using, a facile Cu‐confined thermal conversion strategy of zeolitic imidazolate frameworks (ZIF‐67) pre‐grown on Cu(OH)2 nanowires. Cu ions formed below 450 °C are homogeneously confined within the pores of ZIF‐67 to avoid self‐aggregation, while the existence of CuN bonds further increases the nitrogen content in carbon frameworks derived from ZIF‐67 at higher pyrolysis temperatures. This CuCo@NC electrocatalyst provides abundant active sites, high nitrogen doping, strong synergetic coupling, and improved mass transfer, thus significantly boosting electrocatalytic performances in oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER). A high half‐wave potential (0.884 V vs reversible hydrogen potential, RHE) and a large diffusion‐limited current density are achieved for ORR, comparable to or exceeding the best reported earth‐abundant ORR electrocatalysts. In addition, a low overpotential (145 mV vs RHE) at 10 mA cm−2 is demonstrated for HER, further suggesting its great potential as an efficient electrocatalyst for sustainable energy applications.

Single‐Atom to Single‐Atom Grafting of Pt1 onto FeN4 Center: Pt1@FeNC Multifunctional Electrocatalyst with Significantly Enhanced Properties

“…So far, few strategies have been provided to improve the FeNC PEMFC stability meanwhile deliver a high power density. We noticed that all proposed mechanisms for FeNC deterioration are related with the atomically dispersed active moieties FeN 4 and their close neighborhoods. Therefore, a modulation of FeN 4 moiety at the atomic level may offer an opportunity to improve its stability and put an insight into its degradation mechanism.…”

“…We noticed that all proposed mechanisms for FeNC deterioration are related with the atomically dispersed active moieties FeN 4 and their close neighborhoods. Therefore, a modulation of FeN 4 moiety at the atomic level may offer an opportunity to improve its stability and put an insight into its degradation mechanism. However, no effective approach has been proposed to tune the active moiety of FeNC and its catalytic properties yet.…”

Cobalt–Nitrogen‐Doped Helical Carbonaceous Nanotubes as a Class of Efficient Electrocatalysts for the Oxygen Reduction Reaction

“…TheC o content of l-CCNTs-Co-800 is about 0.4 wt %m easured with the inductively coupled plasma mass spectrometry (ICP-MS). [13] Thecontent of N% and C% in the l-CCNTs-Co-800 measured by an elemental analyzer is 8.6 % and 77.3 %, further indicating the formation of N-doped carbon rather than carbon nitride. [13] Thecontent of N% and C% in the l-CCNTs-Co-800 measured by an elemental analyzer is 8.6 % and 77.3 %, further indicating the formation of N-doped carbon rather than carbon nitride.…”

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

“…The PXRD pattern of the CuCo@NC material has the same diffraction peaks as those of Co@NC ( Figure 2g). [74] To furtheri nvestigate the differenceb etween ZIF-L-Co and ZIF-67 used in this system, thermogravimetric analyses (TGA) of Cu(OH) 2 @ZIF-L-Co andC u(OH) 2 @ZIF-67i nN 2 were performed ( Figure 2i). As shown in the high-angle annular dark field-scanningt ransmission electron microscopy (HAADF-STEM) image and the corresponding EDSm apping of CuCo@NC, the Ne lementw as homogeneously distributed throughout the whole nanoleaf ( Figure S5 in the Supporting Information), whereas Cu and Co were specifically located on the metal nanoparticles( Figure 2h).…”