Cobalt‐Based MOF‐Derived CoP/Hierarchical Porous Carbon (HPC) Composites as Robust Catalyst for Efficient Dehydrogenation of Ammonia‐Borane

Abstract

Transition‐metal phosphides (TMP), particularly cobalt phosphide (CoP) has drawn considerable attention in heterogeneous catalysis during the past few years due to their robust stability, corrosion resistance and low cost. In this work, a series of hierarchically porous carbon supported non‐precious CoP NPs by using Co–MOF‐74 as self‐sacrificed templates have been synthesized through a stepwise calcinations and phosphorization method. The catalytic performance of the resulted CoP@HPC−T composites toward the hydrolytic dehydrogenation of ammonia‐borane (AB) has been systematically investigated, of which, the resultant CoP@HPC−T calcinated at 500 °C showed the best catalytic performance with a TOF value of 27.7 min−1, and relatively low activation energy (42.55 kJ/mol) even comparable to those reported noble metal catalysts. Furthermore the robust structure of CoP@HPC−T compared to the Co@HPC−T counterpart in the recycle tests, demonstrating their great potential for practical application.

Defective Ehanced Subnano-Rh Catalyst Supported on an Ni@Ni-N-C Substrate for Highly Efficient Hydrolytic Dehydrogenation of Ammonia Borane

“…According to refs − , five characteristic peaks could be ascribed to pyridine nitrogen (398.4 eV), Ni–N (399.5 eV), pyrrole nitrogen (400.3 eV), graphitization (401.1 eV), and nitrogen oxide (403.2 eV). The peaks for C 1s at 284.2, 285.2, and 288.7 eV correspond to C–N, CC/C–C, and C–O bonds (Figure e), respectively. − Compared with the support of Ni@Ni-N-C, the binding energies of Ni 2p 3/2 , Ni 2p 1/2 , and nitrogen oxide of Rh/Ni@Ni-N-C (0.74% wt Rh) catalysts have a certain degree of positive deviation, indicating the existence of characteristic electron deficiency in Rh/Ni@Ni-N-C (0.74% wt Rh), and the binding energy of pyridine nitrogen for Rh/Ni@Ni-N-C (0.74% wt Rh) also exhibits a certain negative deviation, indicating that its electron density was significantly higher than that of the support of Ni@Ni-N-C. Furthermore, the relative content of pyridine nitrogen in Rh/Ni@Ni-N-C (0.74% wt Rh) was significantly lower than that in Ni@Ni-N-C, which may attribute to the interaction between Rh and parts of pyridine nitrogen in the carrier, thereby reducing the content of unstable pyridine nitrogen .…”

Cobalt-Based Metal-Organic Frameworks and Their Derivatives for Hydrogen Evolution Reaction

“…MOFs and MOFs-derived materials are excellent catalytic materials (Pan et al, 2018 ; Ma X. C. et al, 2020 ; Ma Y. et al, 2020 ). They have attracted much attention because of their designability and adjustability.…”

“…Recent years, transition metal phosphides (TMPs) have attracted wide attention due to their excellent HER activity, low cost and stability in acidic environments (Tabassum et al, 2017 ; Wang Q. et al, 2018 ; Wang X. et al, 2018a ; Zhang et al, 2018 ; Ma X. C. et al, 2020 ). Unlike the typical layer-structured metal sulfides, TMPs tend to form more isotropic crystal structures.…”

“…During the past few years, a variety of electrocatalysts have been studied for HER, mainly including metals (Xiu et al, 2020 ), metal sulfides (Huang H. et al, 2020b ), metal phosphides (Zhou et al, 2020 ), metal carbides (Ma X. C. et al, 2020 ; Yu H. et al, 2020 ; Yu Y. et al, 2020 ) and carbon-based materials (Wang H.-F. et al, 2020 ; Wang J. et al, 2020 ; Wang X. et al, 2020 ). In general, the electrocatalysis properties could be improved through increasing the number of active sites and the intrinsic activity of each active site (Huang H. et al, 2020b ; Huang Z. et al, 2020 ).…”

Metal–organic framework‐derived phosphide nanomaterials for electrochemical applications

“…In this overview, the advances made to date in terms of MOF‐derived phosphides in energy‐related electrocatalysis, including ingenious‐modulated strategies, various synthetic methods to prepare NiCo bimetallic phosphide MOF‐74 materials, 66 CoP/Fe 2 P@mC nanocomposites, 67 NiFe phosphide nanorods derived from MIL‐88‐Fe 2 Ni MOF (MIL = materials of Institute Lavoisier), 68 bimetallic Ni 0.4 Mn 1.6 P derived from Ni@Mn‐MOF, 69 Ru‐doped bimetallic phosphide derived from 2D MIL‐53 MOF (Figure 6A,B), 70 MOF‐71‐derived layered Co‐CoP/C, 71 Co MOF‐derived CoP@HPC‐T (HPC = hierarchical porous carbon), 72 M16‐ZIF‐67‐CNT‐P (ZIF = zeolitic imidazolate framework, CNT = carbon nanotube), 73 CuP 2 @C from a Cu‐MOF‐derived Cu@C composite, 74 and so on are elaborated. For example, Hou and his team fabricated a superstructure consisting of ultra‐fine CoP x nanoparticles that decorated carbon nanosheets (NSs) with a porous nickel foam (NF) template, which also shows outstanding electron transport properties, mass transport, and trifunctional electrocatalytic activity 75 .…”