Metallophthalocyanine-Based Polymer-Derived Co₂P Nanoparticles Anchoring on Doped Graphene as High-Efficient Trifunctional Electrocatalyst for Zn-Air Batteries and Water Splitting

Abstract

Covalent organic polymers (COPs) provide an interesting platform for constructing the low-cost and highly efficient multifunctional electrocatalysts in view of their tailorable structures and properties. Herein, Co-phthalocyanine-based COPs (CoPc-COPs) are constructed using cobalt tetraaminophthalocyanine (CoPc­(NH2)4) as the organic building unit and phosphonitrilic chloride trimer (Cl6N3P3) as the linker group, which serve as the self-carrier enriched with Co, P, N, and C to derive Co2P nanoparticles anchored on the N, P codoped graphene after carbonization treatment. Benefiting from the unique construction and the metallic property confirmed by density functional theory (DFT) calculations, the Co2P/NPG displays high-efficient trifunctional electrocatalytic performance toward oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER), including excellent oxygen electrocatalytic activity (overpotential of 0.32 V at 10 mA cm–2 for OER, half-wave potential of 0.81 V for ORR) and outstanding stability (98% over 12 h for OER, 89% over 17 h for ORR). Impressively, rechargeable Zn-air batteries (ZABs) that employed Co2P/NPG as the cathode electro-catalyst display a peak power of up to 103.5 mW cm–2 along with a good cycle stability after 55 h. Moreover, the constructed ZABs can be used to power the overall water splitting. Therefore, function-oriented design of metallophthalocyanine-based COPs provides new ways to strategically construct multifunctional electrocatalysts for the wider integrated green energy system.

Activity Promotion of Core and Shell in Multifunctional Core–Shell Co2P@NC Electrocatalyst by Secondary Metal Doping for Water Electrolysis and Zn‐Air Batteries

“…Besides, the electrocatalytic HER/OER/ORR activity of Fe-Co 2 P@Fe-N-C catalyst can be comparable to that of most reported transition metal-based trifunctional electrocatalysts (Figure 3a; Tables S1-S3, Supporting Information), [13,[35][36][37][38][39][40][41][42][43][44][45][46] showing its considerable potential for future electrocatalytic applications. Generally, a good long-term electrochemical stability is also extraordinarily important for electrocatalysis.…”

Phosphate‐Assisted Dispersion of Iron Phosphide in Carbon Nanosheets towards Efficient and Durable ORR Catalysts in Acidic and Alkaline Media

“…In addition, high-resolution XPS spectra of N, P and Fe are also executed. As exhibited in Figure 2c, N 1s has four separated peaks at binding energy (BE) of 398.2, 400.1, 400.9 and 402.7 eV, which represent for pyridinc-N, pyrrolic-N, graphitic-N and oxidized-N. [19,35] The deconvolution of the highresolution P 2p includes five peaks, among which 129.2 and 130.0 eV can be allocated to P 2p 3/2 and P 2p 1/2 of the PÀ Fe bond (Figure 2d). Compared to elemental P (130.2 eV), the P 2p of 129.2 eV is negatively shifted, suggesting that P carries a partial negative charge (δ À ) in iron phosphide compounds.…”

“…In addition to TMPs, recent advances demonstrate that the synergetic effect between carbon matrix and TMPs plays an important role in enhancing the ORR performance, by improvement of electrical conductivity and prevention of nanoparticles' agglomeration. [19][20][21] Moreover, reports and calculations have revealed that heteroatom-doping in carbon materials introduce vacancy defects, and the heteroatom sites synergized with vacancy defects act as the active sites towards ORR. [22][23][24][25] Therefore, combining TMPs with heteroatom-doped carbon is a promising strategy for producing more active sites in ORR catalyst.…”

Self-catalyzed growth of Zn/Co-N-C carbon nanotubes derived from metal-organic frameworks as efficient oxygen reduction catalysts for Zn-air battery

“…2e) is divided into four peaks, which are associated with carbon atom bonds: C-sp 2 (284.6 eV), C-sp 3 (285.5 eV), C-N (286.9 eV), and C=O/C=N (288.9 eV). In the case of N-species, four types of N-containing groups for Zn-NC and Zn-NGC have been verified, including pyridinic (398.5 eV), pyrrolic (400.2 eV), graphitic (401.1 eV), and oxidized (404.3 eV) nitrogen species [40]. The N 1s spectra of ZnCo-NC and ZnCo-NGC can be well-fitted to four peaks located at 398.5, 399.6, 400.2, and 401.2 eV, which correspond to pyridinic-N, Zn/Co-N x , pyrrolic-N, and graphitic-N, respectively (Fig.…”