Synthesis of Pd decorated flower-like NiO composite and its high catalytic performance for CO oxidation under ambient conditions

Abstract

Hierarchically porous Pd/NiO composites were successfully prepared through a hydrothermal and in-situ reduction protocol. NiO nanoparticles less than 10nm aggregated together to form irregular NiO nanosheets and finally composed the flower-like NiO sphere. When Pd nanoparticles were evenly dispersed and loaded, the resulting materials showed high catalytic activity for low temperature CO oxidation especially under ambient conditions. For 3wt% Pd loaded catalyst, T50 for 1 vol% CO conversion was as low as −15°C under a space velocity of 15 000mlh−1gcat−1. The kinetic study revealed the presence of water molecules can drastically lower the activation energy and finally promote the CO oxidation process.