Noble metal-free catalysts supported on carbon for CO 2 electrochemical reduction

Abstract

In the present work, a wide variety of electrocatalysts, involving different metals, synthesis routes and oxidation states, have been prepared and the response towards the CO2 reduction on carbon-supported established. In particular, catalysts based on non-noble metals (Cu, Co, Fe and Ni) supported on carbon black (Vulcan XC-72R) were tested in the electrochemical reduction of CO2. Amorphous oxides of magnetite/maghemite and crystalline CuO and Cu2O oxides obtained by different methodologies were also studied. Previously, the efficiency of the catalysts for the hydrogen formation was evaluated in 0.1M NaHCO3 since it takes place as a competitive reaction during CO2 reduction in aqueous electrolytes. By comparison of the voltammograms in the absence and presence of CO2, an inhibition of the hydrogen evolution was showed for all (metal and oxide-based) catalysts due to the adsorption of species from CO2 reduction (CO2,red). Interestingly, the CO2,red formation on Co and Fesurfaces operating under these conditions has not been stated before. A strong current decrease, and consequently, a higher adsorbate amount, was observed on copper-oxides (75-85 %) vs. the metal catalyst (45 %).

Synthesis, Characterization and Adsorptive Performances of a Composite Material Based on Carbon and Iron Oxide Particles

“…The recorded XRD spectra obtained for three synthesized materials are depicted in Figure 5. By analyzing the presented spectra we can observe that the synthesized materials are heterogeneous containing two different phases: carbon and magnetite [36,37].…”

Electrochemical Carbon Dioxide Reduction in Methanol at Cu and Cu2O-Deposited Carbon Black Electrodes

“…The Faradaic efficiencies for methane and ethylene were similar or better than those obtained with previous works. The reason could not be clarified, and it maybe seems due to the enhancement of the electron transfer mobility [3][4][5][6][7][8][9][11][12][13][14][15][16][17][18][19][20][21][22].…”

“…Guo et al [21] explored the efficient and tunable CO 2 reduction at Co 3 O 4 -carbon dots-C 3 N 4 catalysts. Pérez-Rodríguez et al [22] tested the electrochemical reduction of CO 2 in water at various non-noble metal (Ni, Cu, Co, and Fe) catalysts deposited on commercially carbon black (Vulcan XC-72R).…”

Fe-Based Nano-Materials in Catalysis

“…Tartaj and co-workers [ 16 ] describe in their article entitled “The Iron Oxides Strike Back: …” how the exciting properties of iron oxides, coupled to their low toxicity, stability and economic viability, make them ideal for applications in a broad range of emerging fields. As one of the most significant earth oxides, iron oxide can be employed in the development of active and stable catalytic materials for reforming reactions to produce syngas [ 17 , 18 , 19 , 20 , 21 ], for production of chemicals [ 22 , 23 , 24 ], such as allyl alcohol [ 25 , 26 ], as an active component for catalytic oxidation in exhaust converters [ 27 , 28 ], for hydrodeoxygenation [ 29 , 30 ] and hydrogenation [ 31 , 32 ] reactions, for hydrogen sulfide removal from sewage [ 33 ], for electrochemical reduction of CO 2 [ 34 ], in batteries [ 35 ], in chemical looping processes [ 36 , 37 , 38 , 39 , 40 ], in water gas shift reaction [ 41 , 42 , 43 , 44 ], etc. The use of iron in the proton exchange membrane (PEM) fuel cells [ 43 , 45 ] has also attracted special interest.…”