Double Active Sites in Co–N_x–C@Co Electrocatalysts for Simultaneous Production of Hydrogen and Carbon Monoxide

Abstract

The hydrogen evolution reaction (HER) by electrocatalytic water splitting is a prospective and economical route. However, the approach is severely hindered by the sluggish anodic OER, poor reactivity of electrocatalysts, and low-value-added byproducts at the anode. Herein, formaldehyde was added as an anode sacrificial agent, and a bifunctional Co–N x –C@Co catalyst containing abundant Co–N4 sites and Co nanoparticles was successfully fabricated and evaluated as both a cathodic and an anodic material for the HER and formaldehyde selective oxidation reaction (FSOR), respectively. Co–N x –C@Co displayed a remarkable electrocatalytic performance simultaneously for both HER and FSOR with high hydrogen (H2) and carbon monoxide (CO) selectivity. Density functional theory calculations combined with experiments identified that Co–N4 and Co nanoparticles were dominating active sites for CO and H2 generation, respectively. The coupling tactic of FSOR at the anode not only expedites the reaction rate of HER but also offers a high-efficiency and energy-saving means for the generation of valuable H2/CO syngas.

Sea-Urchin-Like Carbon Nanospheres for Electrocatalytic Dechlorination of 1,2-Dichloroethane

“…As can be seen from Figure S13, the SS-CNRs had a comparatively lower electrochemical surface area compared with CNRs and CNPs, whereas the SS-CNRs possessed the highest kinetics for electrocatalytic dechlorination of 1,2-DCA. Thus, it may be inferred that the high electrocatalytic performance of SS-CNRs benefits from their intrinsic catalytic activity rather than the electrochemical surface area. , Moreover, compared with the previous works (Tables S4 and S5), ,, the FE ethylene and production rate at −2.55 and −2.75 V in this work are relatively higher than previously reported ones, and this has proven that the as-synthesized sea-urchin-like carbon nanosphere catalyst exhibits outstanding electrocatalytic dechlorination performance of 1,2-DCA. Based on the different outcomes for the similar electrocatalytic reaction, it may be confirmed that the unique sea-urchin-like spherical superstructure has played an indispensable role.…”

Carbon-Encapsulated NCO4−β/C Hierarchical Nano-Microflowers for Electrocatalytic Dechlorination of Dichloromethane

“…Taking NCO 4−β /C 1 as an example, the value of I D / I G is 0.4, which indicated the successful coating of carbon on NCO 4−β . This result could be profitable to the electrocatalytic dechlorination of DCM . To further verify the functional groups contained in NCO 4−β and NCO 4−β /C x ( x = 0.5, 1, 2, 3), the Fourier transform infrared spectrare revealed in Figure d.…”

“…33 This result could be profitable to the electrocatalytic dechlorination of DCM. 34 To further verify the functional groups contained in NCO 4−β and NCO 4−β /C x (x = 0.5, 1, 2, 3), the Fourier transform infrared spectrare revealed in Figure 4d. Among them, the large peak around 1628 cm −1 was due to the stretching vibration of H 2 O molecules.…”

Coupling electrocatalytic cathodic nitrate reduction with anodic formaldehyde oxidation at ultra-low potential over Cu2O

“…Formaldehyde (HCHO) is the most reductive aldehyde and is expected to achieve ultra-low aldehyde oxidation via the EOD pathway. [31][32][33] In addition, HCHO has been reported to reduce Cu 2+ to metallic Cu when complexed by EDTA or tartrate and can rapidly reduce Cu(OH) 2 to form Cu 2 O. 34,35 The interaction between HCHO and Cu-based catalysts could satisfy the needs for a special anodic aldehyde oxidation reaction.…”