Wang Xuyu, Li Jing, Xing Jiajun, Zhang Manyu, Liao Rui, Wang Chongtai, Hua Yingjie, Ji Hongbing
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China; Huizhou Research Institute of Sun Yat-sen University, Huizhou, Guangdong, China; School of Chemistry and Chemical Engineering, the Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan Province, Hainan Normal University, Haikou, China.
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China.
J Colloid Interface Sci. 2024 Feb 15;656:104-115. doi: 10.1016/j.jcis.2023.11.095. Epub 2023 Nov 17.
The elimination of formaldehyde at room temperature holds immense potential for various applications, and the incorporation of a catalyst rich in surface hydroxyl groups and oxygen significantly enhances its catalytic activity towards formaldehyde oxidation. By employing a coprecipitation method, we successfully achieved a palladium domain confined within the manganese carbonate lattice and doped with iron. This synergistic effect between highly dispersed palladium and iron greatly amplifies the concentration of surface hydroxyl groups and oxygen on the catalyst, thereby enabling complete oxidation of formaldehyde at ambient conditions. The proposed method facilitates the formation of domain-limited palladium within the MnCO lattice, thereby enhancing the dispersion of palladium and facilitating its partial incorporation into the MnCO lattice. Consequently, this approach promotes increased exposure of active sites and enhances the catalyst's capacity for oxygen activation. The co-doping of iron effectively splits the doping sites of palladium to further enhance its dispersion, while simultaneously modifying the electronic modification of the catalyst to alter formaldehyde's adsorption strength on it. Manganese carbonate exhibits superior adsorption capability for activated surface hydroxyl groups due to the presence of carbonate. In situ infrared testing revealed that dioxymethylene and formate are primary products resulting from catalytic oxidation of formaldehyde, with catalyst surface oxygen and hydroxyl groups playing a crucial role in intermediate product decomposition and oxidation. This study provides novel insights for designing palladium-based catalysts.
室温下甲醛的消除在各种应用中具有巨大潜力，而引入富含表面羟基和氧的催化剂可显著提高其对甲醛氧化的催化活性。通过共沉淀法，我们成功实现了在碳酸锰晶格中限域并掺杂铁的钯域。高度分散的钯与铁之间的这种协同效应极大地增加了催化剂表面羟基和氧的浓度，从而能够在环境条件下实现甲醛的完全氧化。所提出的方法促进了MnCO晶格内限域域钯的形成，从而提高了钯的分散度并促进其部分掺入MnCO晶格。因此，这种方法促进了活性位点的更多暴露并提高了催化剂的氧活化能力。铁的共掺杂有效地分裂了钯的掺杂位点以进一步提高其分散度，同时改变催化剂的电子修饰以改变甲醛在其上的吸附强度。由于碳酸盐的存在，碳酸锰对活化表面羟基具有优异的吸附能力。原位红外测试表明，二氧亚甲基和甲酸盐是甲醛催化氧化的主要产物，催化剂表面的氧和羟基在中间产物的分解和氧化中起关键作用。本研究为设计钯基催化剂提供了新的见解。
