A paper titled "Remarkable effects of hydroxyl species on low-temperature CO (preferential) oxidation over Ir/Fe(OH)_x catalyst" delivered by Dr. Jian Lin was published in Journal of Catalysis.

Article link：http://www.sciencedirect.com/science/article/pii/S0021951714002358

Low-temperature CO oxidation, a prototypical reaction in heterogeneous catalysis, is not only useful as a model reaction to fundamentally study the reaction mechanism or the nature of the catalysts, but also greatly important in many practical applications such as air cleaning, automotive emission control and purifying H₂ for the polymer electrolyte membrane fuel cell (PEMFC). Fe(OH)_x-supported noble metal catalysts exhibited good performance in low-temperature CO oxidation or CO preferential oxidation (PROX), which usually resulted from the high reducibility of Fe(OH)_x. However, we found here that the use of Fe(OH)_x promoted the formation of OH species during PROX over Ir/Fe(OH)_x catalysts (Angew. Chem. Int. Ed. 2012, 51, 2920), which not only greatly lowered the temperature for 100% CO conversion, even to room temperature, but also improved the stability. These OH species originated from the reaction between the adsorbed O on Fe²⁺ sites and the adsorbed H on Ir sites. They changed the reaction route for the oxidation of CO through adsorbed CO and OH with lower activation energy (Ea: ~5.2 kJ/mol) rather than through adsorbed CO and O (Ea: ~15.4 kJ/mol). With further time-resolved mass spectroscopy and diffuse reflectance infrared spectroscopy, the OH species, prior to the adsorbed O, were proved to react with CO directly.