Ni_xCo_y Nanocatalyst Supported by ZrO₂ Hollow Sphere for Dry Reforming of Methane: Synergetic Catalysis by Ni and Co in Alloy

Abstract

Ni x Co y /H-ZrO2 catalysts composed of highly dispersed Ni x Co y nanoparticles supported by mesoporous ZrO2 hollow sphere are synthesized by templating and impregnation processes. According to thermogravimetric analysis, X-ray photoelectron spectroscopy, and dry reforming results, a synergetic reaction mechanism is proposed to explain the better performance of alloy catalysts compared to Ni/H-ZrO2 or Co/H-ZrO2. In dry reforming of methane (DRM) reaction, Ni and Co act as catalysts for CH4 cracking and CO2 reduction, respectively, and the induced carbon deposits on Ni can be oxidized by the active oxygen left on Co, which regenerate the metal surface for the following reaction. Among all the alloy catalysts, the Ni0.8Co0.2/H-ZrO2 catalyst presents the highest activity and stability because the strong metal–support interaction prevents the sintering of nanocatalysts at high temperature and the hollow structure enhances the mass transportation of reactants and products. More importantly, Ni and Co can synergistically balance the speed of CH4 cracking and CO2 reduction, which effectively avoid coke accumulation/catalyst oxidation and ensure fast and stable conversion for DRM reaction.

Engineering heterogenous catalysts for chemical CO2 utilization: Lessons from thermal catalysis and advantages of yolk@shell structured nanoreactors

“…These results were supported by several other works concerning similar NiCo catalysts within the DRM [117,118,[127][128][129][130][131][132][119][120][121][122][123][124][125][126]. The performance of the NiCo bimetallic catalysts has been linked to the ratio of Ni:Co, as well as the selected support material [133].…”

High‐Performance Bimetallic Catalysts for Low‐Temperature Carbon Dioxide Reforming of Methane

“…Similar findings were also reported by Sheng et al for 3.83%Ni0.89%Co/H‐ZrO 2 . The synergistic effect of Ni and Co helped to balance the oxygen species derived from CO 2 reduction and carbon species from CH 4 decomposition, which effectively inhibited catalyst oxidation and coke accumulation.…”

“…The utilization of CO 2 and CH 4 greenhouse gases through dry methane reforming (DRM) is promising for synthesis gas (syngas) production . Syngas is a key chemical intermediate for fuel production through the reaction of Fischer‐Tropsch synthesis.…”

Effects of alloying for steam or dry reforming of methane: a review of recent studies

“…14). 124 However, many reports have described that either too little or too much was not beneficial. For example, Sn-Ni can suppress carbon deposition, but too much Sn-Ni engenders a significant decrease in SRM activity (Fig.…”