Tuning the Adsorption Energy of Methanol Molecules Along Ni‐N‐Doped Carbon Phase Boundaries by the Mott–Schottky Effect for Gas‐Phase Methanol Dehydrogenation

Abstract

Engineering the adsorption of molecules on active sites is an integral and challenging part for the design of highly efficient transition-metal-based catalysts for methanol dehydrogenation. A Mott-Schottky catalyst composed of Ni nanoparticles and tailorable nitrogen-doped carbon-foam (Ni/NCF) and thus tunable adsorption energy is presented for highly efficient and selective dehydrogenation of gas-phase methanol to hydrogen and CO even under relatively high weight hourly space velocities (WHSV). Both theoretical and experimental results reveal the key role of the rectifying contact at the Ni/NCF boundaries in tailoring the electron density of Ni species and enhancing the absorption energies of methanol molecules, which leads to a remarkably high turnover frequency (TOF) value (356 mol methanol mol Ni h at 350 °C), outpacing previously reported bench-marked transition-metal catalysts 10-fold.

Simultaneously Realizing Rapid Electron Transfer and Mass Transport in Jellyfish‐Like Mott–Schottky Nanoreactors for Oxygen Reduction Reaction

“…Besides, the C 1s peaks in HPCM‐5 exhibits a slight shift to lower one compared to MPCM (Figure 2e). These results further indicated that electrons transfer from Fe to N doped graphitic C at the heterojunction interfaces 6,9a,10,18. Overall, the charge regulation by Mott–Schottky effect in HPCM‐5 effectively causes electrons redistribution, forming a fast electron transfer path and enhancing ORR performance, which will be further discussed latter.…”

“…N heteroatom‐doping in carbon can change the charge or spin distribution, which is beneficial to facilitate the O 2 adsorption and then improve the ORR performance 16. What is more, N doping could open the band gap of C by raising the conduction band bottom and lowering the valence band top 3h,9,10. The introduced N atoms are mainly pyridinic‐N (398.6 eV) and graphitic‐N (401.1 eV) in HPCM‐5, as revealed by the N 1s high‐resolution spectra (Figure 2d).…”

“…As a result, the dyadic catalysts have substantially improved the chemical reactivity, selectivity, and stability than their single counterpart. Thus, the concept of Mott–Schottky effect has been applied in many catalyst fields, such as photo‐catalytic,7 nitrogen fixation,8 organic reaction,5a,9 methanol dehydrogenation,10 oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) 6,11. However, to our knowledge, this advanced concept is rarely proposed in ORR electrochemistry.…”

Cobalt Entrapped in N,S‐Codoped Porous Carbon: Catalysts for Transfer Hydrogenation with Formic Acid

“…Researchers have been attempting to replace precious metal catalysts with transition metal catalysts. Recently, transition‐metal‐based N‐doped carbon catalysts (M–N–C, M=Co, Fe, Ni) have received worldwide attention, because they exhibit similar properties to those of noble metal catalysts and can promote number of organic reactions . Subsequently, several efficient M–N–C catalysts have been developed for active and selective hydrogenation of functionalized of nitroarenes with FA .…”

“…Recently,t ransitionmetal-based N-doped carbon catalysts (M-N-C, M = Co, Fe, Ni) have received worldwide attention, [21] because they exhibit similar properties to those of noble metal catalysts and can promote number of organic reactions. [22][23][24][25][26][27] Subsequently,s everal efficient M-N-Cc atalysts have been developed for active and selectiveh ydrogenation of functionalized of nitroarenes with FA. [23,[28][29][30][31] It hasb een provent hat N-dopedc arbon shells play avital role in promoting the catalytic activity and selectivity of these catalysts through as ynergistic effect with cobalt nanoparticles (NPs).…”