2D FeP Nanoframe Superlattices via Space‐Confined Topochemical Transformation

Deng, Yangyang; Xi, Xiangyun; Xia, Yan; Cao, Yangfei; Xue, Shuqing; Wan, Siyu; Dong, Angang; Yang, Dong

doi:10.1002/adma.202109145

Cited by 45 publications

(17 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Elemental mapping confirms the homogenous distribution of Fe, Co, P, C, and O in Co 0.42 Fe 0.58 P @ C superlattices (Figure 1k). Consistent with previous observations, [ 31 ] the formation of hollow CoFeP nanocages from solid CoFeO nanocrystals is attributable to the nanoscale Kirkendall effect, driven by the lower inward diffusion rate of P atoms relative to the outward diffusion rate of Fe, Co, and O atoms (Scheme 1b).…”

Section: Resultssupporting

confidence: 92%

Self‐Templated Synthesis of CoFeP @ C Cage‐In‐Cage Superlattices for Enhanced Electrocatalytic Water Splitting

Deng

Cao

Xia

et al. 2022

Advanced Energy Materials

Self Cite

View full text Add to dashboard Cite

bottleneck of the two half-cell reactions, i.e., hydrogen evolution reaction (HER) [3] and oxygen evolution reaction (OER) [4] .The key issue lies in developing highly efficient and stable electrocatalysts to reduce the overpotential, accelerate reaction kinetics, and thus improve the energy conversion efficiency. [1,2,5] Currently, Pt and RuO 2 (or IrO 2 ) are the benchmark electrocatalysts for the HER and OER, respectively. However, the high cost and scarcity of these precious metal-based catalysts greatly impede their commercialization. [6,7] Moreover, using two different catalysts for the respective half reaction is undesirable for actual electrolyzers requiring the same electrolyte environment, restrained by the incongruity of the optimum pH for each side. [8][9][10] Therefore, breakthroughs in the production of new bifunctional electrocatalysts will greatly facilitate the advancement of electrochemical water splitting.Among various nonprecious catalysts explored, transition metal phosphides (TMPs), such as FeP [11] , CoP [12] , NiP [13] , and MoP [14] , show distinct advantages for overall water splitting by virtue of their elemental abundance and favorable activity. However, monometallic phosphides often show good performance in a half reaction (HER or OER), with poor activity on the other side. [15,16] A number of strategies have therefore been proposed to boost the catalytic performance of TMPs toward overall water splitting. One strategy is to introduce secondary metals to afford heterometallic phosphides, which can optimize the electronic structure of TMPs and thus tailor the kinetic energy barriers, due to the synergistic effect between the two metal components. [9,[17][18][19] Engineering the micro/nanostructures of TMPs has also proven to be capable of effectively reducing the overpotential and facilitating the reaction kinetics. [15,20] To this end, hierarchical porous TMPs have attracted enormous attention owing to their interior voids and large surface area, which can substantially enhance the exposure of active sites, accelerate electrolyte penetration, and shorten ion/electron diffusion pathways during the electrochemical process. [5,20,21] In addition, hybridizing TMPs with conductive components such as carbon, which can facilitate charge transfer and prevent TMPs from aggregation and oxidation during electrocatalysis, has also been widely employed to boost the electrocatalytic performance. [22,23] Designing highly-efficient, cost-effective, and stable electrocatalysts for water splitting is of great significance for implementing renewable energy technologies. Herein, a self-templated strategy is employed to fabricate 2D porous electrocatalysts of heterometallic phosphides featuring a cage-in-cage superlattice architecture. The as-made heterometallic phosphide electrocatalysts, comprising a layer of close-packed CoFeP nanocages intimately embedded in an interconnected carbon-cage framework, are converted from carbon-coated CoFeO nanocrystal superlattices by one-step phosphidation. Benefiting f...

show abstract

Section: Resultssupporting

confidence: 92%

Self‐Templated Synthesis of CoFeP @ C Cage‐In‐Cage Superlattices for Enhanced Electrocatalytic Water Splitting

Deng

Cao

Xia

et al. 2022

Advanced Energy Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…[59][60][61] The P 2p 3/2 peak exhibits a slight shift to a lower energy level from elemental P ($130.2 eV), indicative of electron transfer from the metal to the P atom and the formation of a phosphide. 72,73 Such electron transfer plays a key role in hydrogen production because negatively charged (δ À ) P atoms act as proton acceptor sites that endow the TMPs with high HER activity. 21,23,26 Therefore, the metal-P bonding to phosphate ratio significantly affects the catalytic activity, as reported in previous studies.…”

Section: Resultsmentioning

confidence: 99%

“…The MoP spectra show a large peak (134.3 eV) and small doublets (130.4 and 129.5 eV) in the P 2p region, which can be assigned to phosphate (PO 4 3− ) and P bonded to a metal, respectively (Figure 5D). 59‐61 The P 2p 3/2 peak exhibits a slight shift to a lower energy level from elemental P (~130.2 eV), indicative of electron transfer from the metal to the P atom and the formation of a phosphide 72,73 . Such electron transfer plays a key role in hydrogen production because negatively charged (δ − ) P atoms act as proton acceptor sites that endow the TMPs with high HER activity 21,23,26 .…”

Section: Resultsmentioning

confidence: 99%

Transition‐metal‐incorporated molybdenum phosphide nanocatalysts synthesized through post‐synthetic transformation for the hydrogen evolution reaction

Kim

Park

Lee

et al. 2022

Intl J of Energy Research

View full text Add to dashboard Cite

Summary Post‐synthetic chemical transformation is a recently emerging nanomaterial manufacturing method for obtaining materials with precisely modulated properties. Through post‐synthetic transformation methods, foreign elements are exchanged or incorporated into presynthesized nanoparticles (NPs). However, metal phosphides have not been primarily used as starting materials because of their strong bonding characteristics. In this study, we synthesized bimetallic transition metal phosphide (TMP) NPs through a cation addition reaction using amorphous molybdenum phosphide (MoP) as the starting material, which is a promising catalyst for the hydrogen evolution reaction (HER). The additional metal elements, namely Co and Ni, were successfully incorporated into the parent MoP NPs, which led to only marginal changes in size or shape, even after 12 hours of reaction. Because morphological factors strongly influence catalytic activity, nanocatalysts with identical morphologies provide a direct comparison among NPs with various chemical properties. The Co‐ and Ni‐incorporated MoP NPs exhibited significantly enhanced catalytic activities for the HER, with similar electrochemically active surface areas. In particular, Co‐1.5 h‐MoP showed the highest HER activity (167 mV at −10 mA cm−2) and durability among the samples in 0.5 M H2SO4. Such an improvement in catalytic activity through the cation addition reaction may be ascribed to the difference in the electronegativities of the original and newly added metal cations, as confirmed by X‐ray photoelectron spectroscopy (XPS), resulting in abundant metal‐P bonding and oxidation resistivity. This study provides a new advanced platform for directly analyzing the inherent characteristics of nanomaterials for diverse applications, especially electrocatalysis.

show abstract

“…[21] Iron-based metal phosphides (IMPs) illustrate excellent activity toward water dissociation and can quickly generate protons during the alkaline hydrogen evolution reaction (HER). [22,23] Besides, IMPs are also considered as promising OER catalysts. [24][25][26] Unsupported transition metal phosphides have low conductivity, easily being agglomerated and deactivated.…”

Section: Introductionmentioning

confidence: 99%

Wood‐Derived Monolithic Catalysts with the Ability of Activating Water Molecules for Oxygen Electrocatalysis

Zhang

Liu

Wang

et al. 2022

Small

View full text Add to dashboard Cite

advantages of zinc-air batteries (ZABs), such as high energy density and theoretical capacity, low cost, high safety, and stability, endow them with huge application potential in the field of energy storage and conversion. [4,5] During the charging and discharging process of ZABs, oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play a crucial role in determining the energy conversion efficiency. [6] Both of ORR and OER involve complex multiple electron transfer processes. [7] The inherently slow kinetics of ORR and OER leads to lofty overpotentials, resulting in low energy efficiency, and low power density of ZABs. [8] Noble metal-based electrocatalysts (such as Pt/C, RuO 2 , IrO 2 ) exhibit superior oxygen electrocatalytic activity, while the high cost and deficient stability hinder their industrial-scale application in the rechargeable ZABs. [9,10] Therefore, it is urgent to develop stable and efficient nonnoble metal-based ORR/OER bifunctional electrocatalysts to facilitate the development of ZABs. [11] In alkaline solution, the favorable four-electron ORR for ZABs follows: 1) O 2 (g)where * denotes the active site. [12] The second and fourth steps both involve the coupling process of activated Oxygen reduction reaction (ORR) is the key reaction on cathode of rechargeable zinc-air batteries (ZABs). However, the lack of protons in alkaline conditionslimits the rate of ORR. Herein, an activating water strategy is proposed to promote oxygen electrocatalytic activity by enhancing the proton production from water dissociation. FeP nanoparticles (NPs) are coupled on N-doped wood-derived catalytically active carbon (FeP-NWCC) to associate bifunctional active sites. In alkaline, FeP-NWCC possesses outstanding catalytic activities toward ORR (E 1/2 = 0.86 V) and Oxygen evolution reaction (OER) (overpotential is 310 mV at 10 mA cm −2 ). The liquid ZABs assembled by FeP-NWCC deliver superior peak power density (144 mW cm −2 ) and cycle stability (over 450 h). The quasi-solid-state ZABs based on FeP-NWCC also display excellent performances. Theoretical calculation illustrates that the superb bifunctional performance of FeP-NWCC results from the elevated dissociation efficiency of water via FeP NPs to assist the oxygen catalytic process. The strategy of activating water provides a new perspective for the design of ORR/OER bifunctional catalysts. This work is a model for the application of forest biomass.

show abstract

2D FeP Nanoframe Superlattices via Space‐Confined Topochemical Transformation

Cited by 45 publications

References 52 publications

Self‐Templated Synthesis of CoFeP @ C Cage‐In‐Cage Superlattices for Enhanced Electrocatalytic Water Splitting

Self‐Templated Synthesis of CoFeP @ C Cage‐In‐Cage Superlattices for Enhanced Electrocatalytic Water Splitting

Transition‐metal‐incorporated molybdenum phosphide nanocatalysts synthesized through post‐synthetic transformation for the hydrogen evolution reaction

Wood‐Derived Monolithic Catalysts with the Ability of Activating Water Molecules for Oxygen Electrocatalysis

Contact Info

Product

Resources

About