S-Doped Ni^II-Triazolate Derived Ni–S–C Catalyst for Electrochemical CO₂ Reduction to CO

Abstract

Metal heteroatom doped carbon materials display remarkable catalytic performance in the electrochemical CO 2 reduction (ECR) because the doped heteroatoms can significantly change the local density of state and electronic structure of carbon, which induces charge polarization or structural defects. Herein, we synthesized S-doped Ni II -triazolate precursors with high purity and crystallinity through a simple one-step hydrothermal method. The high-temperature pyrolysis process produced a series of Ni−S−C T (T = 800, 900, 1000 °C) materials with Ni 3 S 2 as the main component. It resulted in significant carbon structure defects in the catalyst, which increased the specific surface area and pore volume, providing a basis for improving the ECR activity. Through the structural characterizations of powder X-ray diffraction (PXRD), Raman, X-ray photoelectron (XPS), Brunauer−Emmett−Teller (BET), transmission electron microscopy (TEM), and electrochemical characterizations of linear sweep voltammetry (LSV), chronoamperometry (i−t curve), electrochemical impedance spectroscopy (EIS), and electrochemical active surface area (ECSA), as well as gaseous product analysis, we can build the structural-performance relationship. Ni−S−C T catalysts all reached the highest CO Faraday efficiency at −1.5 V vs Ag/AgCl potential, among which Ni−S−C 1000 exhibited the best catalytic activity (FE CO of 66.6% and j CO of 1.28 mA/ cm 2 ). It also displayed excellent stability and recyclability, which could realize the efficient reuse of the catalyst. In addition, the density functional theory (DFT) calculation was carried out on Ni 3 S 2 to illustrate the ECR activity origination. It is the first report on Ni 3 S 2 -based catalysts in the application of ECR.

MOF-derived transition metal-based catalysts for the electrochemical reduction of CO2to CO: a mini review

“…7a). 25 Ni–S–C 1000 was revealed to exhibit the best CO 2 RR catalytic performance with 66.6% FE CO and good stability. The high temperature caused numerous defects and increased the pore volume.…”

“…The d-orbital of transition metals is filled with electrons close to the Fermi level, and the variability of the electron configuration of the d-orbital was reported to promote the desorption of intermediates and accelerate the reaction kinetics. 24,25 Meanwhile, porous carbon-based materials with unique characteristics are also considered favourable catalysts or support for electrocatalysis. 26 Metal-organic frameworks (MOFs) have been studied a lot in recent years due to the large surface area and tuneable structure by variation of the metal cation and organic linkers.…”

The Application of Transition Metal Sulfide Nanomaterials and Their Composite Nanomaterials in the Electrocatalytic Reduction of CO2: A Review

“…In addition, methane was the preferred product with the Fe/Ni nanoparticles, while hydrogen was the preferred product with pure greigite. Zhang et al studied the synthesis of Ni-S-C nanoparticles from S-doped Ni-triazolate starting material for the CO 2 reduction to CO [180]. The authors synthesized a pure Ni(II)-triazolate complex as a starting material followed by pyrolysis at three temperatures, 800, 900, and 1000 • C, which resulted in a Ni 3 S 2 material with carbon.…”

Exfoliated 2D Layered and Nonlayered Metal Phosphorous Trichalcogenides Nanosheets as Promising Electrocatalysts for CO2 Reduction

“…More importantly, their study revealed that the transition‐metal, Ni atoms, played as CO 2 ECR active sites, whereas S atoms improved its electrocatalytic activity synergistically by comparing these two S‐doped and S‐free catalysts [18] . These electrocatalytic CO 2 reduction reactions could also be boosted acquired by using the powerful strategy of sulfur activation in Fe‐NS−C, [19] Ni−S−C T [20] and so on. Furthermore, the different central earth‐abundant transition‐metal atoms (Mn, Fe, Co, Ni, Cu, Sn⋅⋅⋅) have been explored for CO 2 reduction in numerous research groups to investigate the effect of central metal on catalytic activity and selectivity [21] .…”