Pyrolytic Carbon‐coated Cu‐Fe Alloy Nanoparticles with High Catalytic Performance for Oxygen Electroreduction

Abstract

Well-dispersed carbon-coated or nitrogen-doped carbon-coated copper-iron alloy nanoparticles (FeCu@Co r FeCu@CÀN) in carbon-based supports are obtained using a bimetallic metal-organic framework (Cu/Fe-MOF-74)o ra mixture of Cu/Fe-MOF-74 and melamine as sacrificial templates and an active-component precursor by using apyrolysis method.T he investigation resultsa ttest formation of CuÀ Fe alloy nanoparticles. The obtained FeCu@Cc atalyst exhibits ac atalytic activity with ah alf-wave potential of 0.83 Vf or oxygen reduction reaction (ORR) in alkalinem edium, comparable to that on commercial Pt/C catalyst (0.84 V).T he cata-lytic activity of FeCu@CÀNf or ORR (E half-wave = 0.87 V) outshinesa ll reported analogues. The excellent performance of FeCu@CÀNs hould be attributedt oachange in the energy of the d-band center of Cu resulting from the formationo f the copper-iron alloy,t he interaction between alloy nanoparticlesa nd supports and N-dopingi nt he carbon matrix. Moreover,F eCu@C and FeCu@CÀNs how better electrochemicals tability and methanol tolerance than commercial Pt/C and are expected to be widely used in practical applications.

Impact of Heterometallic Cooperativity of Iron and Copper Active Sites on Electrocatalytic Oxygen Reduction Kinetics

“…[3][4][5]17 The improvement of the 4eselectivity is crucial for developing practical non-PGM catalysts. To improve the ORR activity and selectivity of Fe-N-C, heterometal-doped Fe-N-C catalysts of (M,Fe)-N-C (M = Mn, 18 Co, [19][20] Ni 21 or Cu [22][23][24][25][26][27][28][29][30] ) have been synthesized. [31][32] In nature, a highly selective non-PGM ORR catalysts with heterobimetallic active sites is known: a metalloenzyme of cytochrome c oxidase (CcO).…”

“…16,[37][38][39][40] Cu-doped Fe-N-C, (Cu,Fe)-N-C, electrocatalysts have also been synthesized for the ORR and synergistic effects of the copresence of iron and copper active sites on the ORR activity have been found. [22][23][24][25][26][27][28][29][30] Furthermore, the suppression of the H2O2 production was also observed for (Cu,Fe)-N-C electrocatalysts, compared with the corresponding Cu-N-C and Fe-N-C catalysts. 28 However, heterobimetallic effects of Cu and Fe active sites on the ORR kinetics remain unclear although intensive kinetic studies have been done for single metallic M-N-C catalysts such as Fe-N-C. [41][42][43] Herein, we report synthesis, characterization and kinetic analysis of Cu-, Fe-and N-doped carbon nanotubes, (Cu,Fe)-N-CNT, for the ORR in acidic media.…”

Trace FeCu@PC Derived from MOFs for Ultraefficient Heterogeneous Electro-Fenton Process: Enhanced Electron Transfer and Bimetallic Synergy

“…For FeCu@PC-800/6, the peak at −0.59 V belonged to the reduction reaction between H 2 O 2 and Fe or Cu in the N 2 -saturated condition, whereas no reduction peaks appeared in the CV curves of Fe@PC-800/6 (Figure a), indicating that FeCu@PC-800/6 exhibited better catalytic activity . And the anodic peaks at −0.30 and 0.47 V of FeCu@PC-800/6 in the N 2 -saturated electrolyte were assigned to redox reactions of Fe and Cu species . R ct at high frequency from fitting of Nyquist was obtained to evaluate the rate of electron transfer and electrocatalytic activity (Figure b).…”

Efficient Trimetallic Metal‐Organic‐Framework Derived Cu/Fe3C/N−C Electrocatalysts for Oxygen Reduction

“…Among various choices of second metal, Cu heteroatom has sparked considerable interest due to its unique catalytic or promoting role toward ORR [27,32–43] . For instance, Wang's group designed an outstanding Cu−Fe−N−C electrocatalyst simulating the cytochrome c oxidase (CcO), in which the Cu‐N x active site exhibits synergism with the Fe−N x active site during ORR [27] .…”

“…Among various choices of second metal, Cu heteroatom has sparked considerable interest due to its unique catalytic or promoting role toward ORR. [27,[32][33][34][35][36][37][38][39][40][41][42][43] For instance, Wang's group designed an outstanding CuÀ FeÀ NÀ C electrocatalyst simulating the cytochrome c oxidase (CcO), in which the Cu-N x active site exhibits synergism with the FeÀ N x active site during ORR. [27] Mu's team reported a Cu, Fe-embedded carbon composite (Cu@FeÀ NÀ C) from ZIF-8 (ZIF = Zeolitic Imidazolate Frameworks), which shows a superior ORR performance over the FeÀ NÀ C counterpart owing to the multiple roles of Cu atom.…”