Molecular‐Level Insights into the Notorious CO Poisoning of Platinum Catalyst

Abstract

Carbon monoxide (CO) is notorious for its strong adsorption to poison platinum group metal catalysts in the chemical industry. Here, we conceptually distinguish and quantify the effects of the occupancy and energy of d electrons, emerging as the two vital factors in d-band theory, for CO poisoning of Pt nanocatalysts. The stepwise defunctionalization of carbon support is adopted to fine-tune the 5d electronic structure of supported Pt nanoparticles. Excluding other promotional mechanisms, the increase of Pt 5d band energy strengthens the competitive adsorption of hydrogen against CO for the preferential oxidation of CO, affording the scaling relationship between Pt 5d band energy and CO/H 2 adsorption energy difference. The decrease of Pt 5d band occupancy lowers CO site coverage to promote its association with oxygen for the total oxidation of CO, giving the scaling relationship between Pt 5d occupancy and activation energy. The above insights outline a molecular-level understanding of CO poisoning.

Study on Waste Acid Modificated Industrial Solid Waste Aluminum Ash to Prepare Environmental Functional Materials to Remove Fluoride Ions in Wastewater

“…Due to the doping of oxalic acid, the O-atom content was increased after the modification. BET trial showed (shown in Figure 2) that calcination increased the specific surface area (276.12 m 2 /g) relative to SAA (191.09 m 2 /g), while C (X °C) -SAA had a larger specific surface area, which was favorable for F − to have sufficient adsorption site (Zhang et al, 2022b). Meanwhile, the specific surface of C-SAAoa was increased to 335.38 m 2 /g.…”

“…2022a) (0.1-8%). The regeneration performance of the material was studied for eight cycles (Yang et al, 2022b). Both C (X °C) -SAA and C-SAAoa were applied to a batch of adsorption experiments to determine the performance of this modification.…”

Low Platinum-Content Electrocatalysts for Highly Sensitive Detection of Endogenously Released H2O2

“…Although noble metals exhibit good catalytic performance, their high cost and poison susceptibility [ 64 ] limit their potential for large-scale applications and emphasise the demand for alternative, less expensive and readily available high-efficiency catalytic materials. One of the biggest threats to platinum catalytic performance is CO contamination during heterogeneous catalysis.…”

“…One of the biggest threats to platinum catalytic performance is CO contamination during heterogeneous catalysis. This interference results from the molecular structure of CO, whose triple bond justifies the strong binding capacity on the platinum surface, hindering the analyte from accessing the active catalytic sites available for heterogeneous catalysis [ 64 ]. However, the platinum electrocatalyst’s tolerance to carbon monoxide poisoning can be improved by doping the platinum with other materials such as transition metals [ 65 ], oxides or high-surface-area carbonaceous such as multi-walled carbon nanotubes [ 66 ].…”

“…The second atom within the electrocatalyst provides a vital strategic variation in its shape, size, and morphology, resulting in the amendment of its chemical and physical properties. Effectively, adding a second element to the metallic structure provides the synergistic effect of both materials, along with a cost reduction in the electrocatalyst due to the decline in the amount of most expensive metal, e.g., platinum [ 64 ]. Compared with the corresponding mono-metal NPs, bimetallic blends reveal higher catalytic activity, more reliable resistance to deactivation, and excellent catalytic selectivity.…”