Microenvironment Effects in Electrocatalysis: Ionic‐Liquid‐Like Coating on Carbon Nanotubes Enhances the Pd‐Electrocatalytic Alcohol Oxidation

Abstract

A new catalyst consisting of ionic liquid (IL)-functionalized carbon nanotubes (CNTs) obtained through 1,3-dipolar cycloaddition support-enhanced electrocatalytic Pd nanoparticles (Pd@IL(Cl(-))-CNTs) was successfully fabricated and applied in direct ethanol alkaline fuel cells. The morphology, structure, component and stability of Pd@IL(Cl(-))-CNTs were systematic characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Raman spectra, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The new catalyst exhibited higher electrocatalytic activity, better tolerance and electrochemical stability than the Pd nanoparticles (NPs) immobilized on CNTs (Pd@CNTs), which was ascribed to the effects of the IL, larger electrochemically active surface area (ECSA), and greater processing performance. Cyclic voltammograms (CVs) at various scan rates illustrated that the oxidation behaviors of ethanol at all electrodes were controlled by diffusion processes. The investigation of the different counteranions demonstrated that the performance of the IL-CNTs hybrid material was profoundly influenced by the subtly varied structures of the IL moiety. All the results indicated that the Pd@IL(Cl(-))-CNTs catalyst is an efficient anode catalyst, which has potential applications in direct ethanol fuel cells and the strategy of IL functionalization of CNTs could be available to prepare other carbonaceous carrier supports to enhance the dispersivity, stability, and catalytic performance of metal NPs as well.

Modification of a Pd-loaded electrode with a carbon nanotubes–polypyrrole interlayer and its dechlorination performance for 2,3-dichlorophenol

“…The electrochemical active surface areas (EASA) of the prepared electrodes were calculated in light of the literatures. [45][46][47] EASA z Q/Km, where charge Q is based on the charge of hydrogen atoms adsorption/desorption in the CV test, m is the mass of Pd of the prepared electrodes and K is the Pd conversion factor which is 210 mC cm À2 . The calculated EASA values were shown in Table 1, the EASA of Pd/CNTs-PPy/Ti electrode was improved to 16.35 m 2 g À1 , which increased 58.7% compared with that of the Pd/Ti electrode, 10.30 m 2 g À1 .…”

Nanocatalysts for Electrocatalytic Oxidation of Ethanol

“…Therefore, finding appropriate supports that are stable under given electrochemical www.chemsuschem.org conditions is highly desired. In this regard,c arbon nitrides (CN); [252][253][254][255] metal oxides; [27,[256][257][258] titanium nitrides (TiN); [259] tungstenc arbide (W x C); [260] conducting polymers; [261] carbon nanotubes (CNTs); [262] graphiticm esoporousc arbon (GMC); [263] N-doped carbon; [264] carbon containing Ni, N, andS ; [265] ionicliquid-functionalized carbon nanotubes (IL-CNTs); [266] and nitrogen-doped truncated carbon nanotubes inserted into nitrogen-doped graphene nanosheets (NCNTs@NGS), [267] instead of conventional carbon black, have been employed as supports for noble-metal nanoparticles to enhancet heir durability and corrosion tolerance during electrocatalytic ethanol oxidation.…”

Beyond solvents and electrolytes: Ionic liquids-based advanced functional materials

“…[297] Furthermore, the solubility of the IL-functionalized MWCNTs in water and organic solvents could be reversibly switched by anion exchange. [298] The counterions in IL-modified carbon materials can be further extended to functional anions such as photoactive, [305] electrochemically active, [299,304] and metal-containing anions, [302,303] which may enable their potential applications in lubrication, [306] catalysis, [302,307,308] electrochemistry, [299] and so on. as-prepared hybrids can be directly explored as electrocatalysts for methanol oxidation reactions and exhibit higher electrocatalytic activity than the commercial C/Pt catalyst.…”