Synergistic electrocatalysis of N,Nʹ-bis(salicylidene)-ethylenediamine-cobalt(II) and conductive carbon black (BP) for high efficient CO2 electroreduction

Abstract

Gas diffusion electrodes (GDEs) modified with N, N -Bis(salicylidene)-ethylenediamine-cobalt(II) (Cosalen) and conductive carbon black (BP) have been prepared. It is demonstrated that modified BP-Cosalen/GDE electrode is able to catalyze CO 2 reduction in a more efficient and selective manner than that of bulk Cosalen/GDE in 0.5 M KHCO 3 solution. In the presence of 60 wt% of BP, the as-prepared BPCosalen/GDE electrode exhibits the highest activity for catalyzing CO 2 reduction reaction, wherever increase or decrease the amount of BP do not benefit to CO 2 reduction. Compared to other BP-Cosalen/GDE electrodes, the BP-Cosalen/GDE60 shows the most positive onset potential, and the maximum current density reaches 21 mA cm −2 . The improved catalytic activity is largely due to the excellent electrical conductivity and the developed pore structure of BP which provides more active phases for the electrochemical reduction of CO 2 . Further analysis of reduction product reveals that the product on BP-Cosalen/GDE60 electrode is formate in 0.5 M KHCO 3 electrolyte. The highest faradaic efficiency reached 27 % along with the production rate of formate as much as 0.44 mM.

Chemically modified electrode based on dihexadecyl hydrogen phosphate and carbonaceous materials: improvement of analytical and electrochemical features applied to uranium determination

“…The image obtained from the dispersion containing DHP and CB (Fig. 1a) shows the presence of combined spherical particles forming agglomerates, as already reported by Fu et al [40]. Through the SEM image depict in Fig.…”

“…Therefore, DHP has been widely used in the development of sensors, biosensors, and modified electrodes [27,[29][30][31] combined with nanomaterials such as multi-walled carbon nanotubes (MWCNT) [31,32], carbon black (CB) [33][34][35], and metallic nanoparticles [26,30] improving the methods analytical performance. Among these materials, CB stands out for electrochemistry point of view once present high surface area, high conductivity, low background current, wide potential window, thermal and electrical stability, and a very low cost [36][37][38][39][40].…”

Recent advances in catalytic CO2 reduction by organometal complexes anchored on modified electrodes

“…These salen ligand complexes showed long stability and produced more quantity of hydrocarbons and CO at a 10-25% less overpotential than their respective metals, with a total Z value of 74% for the Ni complex and 25% for Cu the complex at À1.5 V and À1.8 V vs. Ag/AgCl, respectively. The catalyst (N,N-bis(salicylidene)-ethylenediamine-Co) was dispersed in carbon black, 32 and the mixture was covered with Nafion over the GDE. The electrode with 60 wt% exhibited the best activity for CO 2 reduction in aqueous solution, due to the right balance of porosity and conductivity of the carbon black mixture.…”