Electrodes Based on Carbon Aerogels Partially Graphitized by Doping with Transition Metals for Oxygen Reduction Reaction

Abstract

A series of carbon aerogels doped with iron, cobalt and nickel have been prepared. Metal nanoparticles very well dispersed into the carbon matrix catalyze the formation of graphitic clusters around them. Samples with different Ni content are obtained to test the influence of the metal loading. All aerogels have been characterized to analyze their textural properties, surface chemistry and crystal structures. These metal-doped aerogels have a very well-developed porosity, making their mesoporosity remarkable. Ni-doped aerogels are the ones with the largest surface area and the smallest graphitization. They also present larger mesopore volumes than Co- and Fe-doped aerogels. These materials are tested as electro-catalysts for the oxygen reduction reaction. Results show a clear and strong influence of the carbonaceous structure on the whole electro-catalytic behavior of the aerogels. Regarding the type of metal doping, aerogel doped with Co is the most active one, followed by Ni- and Fe-doped aerogels, respectively. As the Ni content is larger, the kinetic current densities increase. Comparatively, among the different doping metals, the results obtained with Ni are especially remarkable.

Ultrasmall Iron Fluoride Nanoparticles Embedded in Graphitized Porous Carbon Derived from Fe‐Based Metal Organic Frameworks as High‐Performance Cathode Materials for Li Batteries

“…The I D /I G ratio of the graphitized carbon obtained from the MIL‐53 sintered at 900 °C is 0.923. This result confirms that the carbon obtained by carbonizing MIL‐53 is highly graphitized . And for comparison we also sintered MIL‐53 at a lower temperature (500 °C) and the Raman spectra presenting typical amorphous carbon shape (Figure S3).…”

Hierarchical Doped Gelatin-Derived Carbon Aerogels: Three Levels of Porosity for Advanced Supercapacitors

“…For materials with a narrow hysteresis loop, the modeling of either the adsorption and desorption branches of nitrogen isotherms will produce similar pore size distributions, whereas the latter results will be notably different for materials with a prominent hysteresis loop. Figure 3 b shows the representative pore distribution for the aerogels where the curve is the result of the modeling of the desorption isotherm using the Cohan equations following the Barrett−Joyner−Halenda method, an approach previously used to model the pore distribution for similar graphene-based and other carbon aerogels [ 34 , 35 , 36 , 37 ].…”

“…The Barrett–Joyner–Halenda (BJH) model was used to calculate the pore size distribution within the 3D framework. The nitrogen isotherms were used to determine the pore size distributions in the meso- (2–50 nm) and micropore (<2 nm) regimes as a function of the temperature treatment following the approach previously reported for similar graphene-based and other carbon aerogels [ 34 , 35 , 36 , 37 ]. The electrochemical performance of the synthesized electrode materials was characterized by cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS).…”

Binary and Ternary 3D Nanobundles Metal Oxides Functionalized Carbon Xerogels as Electrocatalysts toward Oxygen Reduction Reaction

“…Metal-doped carbon xerogels were prepared from resorcinol and formaldehyde monomers through the sol–gel method published elsewhere [ 31 ]. Briefly, resorcinol (R) and formaldehyde (F) were mixed together with a molar ratio of 1:2 in the presence of water (W) as a solvent and metal acetate salt as the dopant (C).…”