Abstract
The Co3O4 nanoparticles,dominated by a catalytically active(110)lattice plane,were synthesized as a low-temperature NOx adsorbent to control the cold start emissions from vehicles.These nanoparticles boast a substantial quantity of active chemisorbed oxygen and lattice oxygen,which exhibited a NOx uptake capacity commensurate with Pd/SSZ-13 at 100 ℃.The primary NOx release temperature falls within a temperature range of 200-350 ℃,making it perfectly suitable for diesel engines.The charac-terization results demonstrate that chemisorbed oxygen facilitate nitro/nitrites intermediates formation,contributing to the NOx storage at 100 ℃,while the nitrites begin to decompose within the 150-200 ℃ range.Fortunately,lattice oxygen likely becomes involved in the activation of nitrites into more stable nitrate within this particular temperature range.The concurrent processes of nitrites decomposition and its conversion to nitrates results in a minimal NOx release between the temperatures of 150-200 ℃.The nitrate formed via lattice oxygen mainly induces the NOx to be released as NO2 within a temperature range of 200-350 ℃,which is advantageous in enhancing the NOx activity of downstream NH3-SCR catalysts,by boosting the fast SCR reaction pathway.Thanks to its low cost,considerable NOx absorption capacity,and optimal release temperature,CO3O4 demonstrates potential as an effective material for passive NOx adsorber applications.
基金项目
National Natural Science Foundation of China(22006044)
National Natural Science Foundation of China(22006043)
External Cooperation Program of Science and Technology Planning of Fujian Province(202310018)
Fujian Province Science and Technology Program Funds(2020H6013)
National Engineering Laboratory for Mobile Source Emission Control Technology(NELMS2020A03)
Scientific Research Funds of Huaqiao University(605-50Y200270001)
NETL
NSTL
万方数据