A Theory/Experience Description of Support Effects in Carbon-Supported Catalysts

Abstract

Fermi level in vii) are shown in purple in ii)-vi) with an iso-value of ±0.003 a.u. Reprinted with permission from ref 57 . Copyright 2014 from the Royal Society of Chemistry; b) Molecular model of a corannulene-like element functionalized with three carboxylic groups from two different perspectives in the cpk representation (on the left). The final structure (190 elements in a cubic cell of 60 Å in size) obtained from random packing of the individual elements (on the right). Cyan: carbon, red: oxygen, white: hydrogen. Reprinted with permission from ref 59 Copyright 2017 from Elsevier; c) Side-views of Ru13 adsorbed on Gr-DV-2COOH site before (on left panel) and after a proton jump (right panel). C atoms are in black, O in red, H in with white and Ru in mocha. Reprinted with permission from ref 60 Copyright 2014 from Elsevier; and d) Spin-density projection in µB/a.u. 2 on the graphene plane around i) the hydrogen chemisorption defect (∆) and ii) the vacancy defect in the a sublattice. Carbon atoms corresponding to the a sublattice (o) and to the b sublattice (•) are distinguished. Simulated STM images of the defects are shown in iii) and iv), respectively. Reprinted with permission from ref 61 .

3D Ruthenium Nanoparticle Covalent Assemblies from Polymantane Ligands for Confined Catalysis

“…The effects of confinement in carbon materials have been identified as possible levers to modify catalytic performances. 95 It has been shown that soft confinement effects, such as reactant enrichment or rapid diffusion, will directly affect the kinetics of the reaction. Hard effects, like the charge transfer between the metal and the support, will also affect activity/selectivity and stability.…”

Directing nitrogen-doped carbon support chemistry for improved aqueous phase hydrogenation catalysis

“…20,21 The ability to direct N-containing functionality on a porous carbon structure is potentially advantageous with regard to NP size/distribution, NP support attachment as well as NP electronic structure. [22][23][24][25][26] Furthermore, N-doping can also lead to improved oxidation and catalyst stability. 27 Using HTC to produce carbon materials is also attractive with respect to directing material properties (e.g.…”

Hydrogen Spillover in the Fischer‐Tropsch Synthesis on Carbon‐supported Cobalt Catalysts

“…In addition to the influence of Co particle size and crystalline structure, many complex phenomena occurring on the catalyst surface affect the catalytic performance, one of them being the migration of H atoms from metallic particles to the support. This phenomenon, called hydrogen spillover, has been widely discussed in the literature for catalysts supported on oxides or carbon materials . In FTS, hydrogen spillover has been only invoked to explain the role of noble metals (Pt, Ru, Au) as promoters for Co reduction in Co/Al 2 O 3 or Co/C catalysts .…”