Paving the way for surface modification in one-dimensional channels of mesoporous materials via plasma treatment

• Energetic plasma particles can transfer into one-dimensional mesoporous channels.
• Plasma treated surface can provide more reactive sites for amine modification.
• Plasma treated surface can efficiently promote the rate of amine modification.
• In-situ coordination of Ag nanoparticles reflected the uniform amine modification.
• The resulted material showed a higher CO2 adsorption capacity.

Plasma technology, an efficient and important approach for the surface modification, has been widely adopted for the treatment on the exposed surface of planar substrates. In this work, plasma treatment was demonstrated to be an effective way for the internal surface modification in one-dimensional channels of mesoporous SBA-15 particles, which is not a general planar substrate. Upon the plasma treatment in O2 atmosphere, the silanol groups on the surface of channels were intensively activated, as a result, large amounts of amine groups (2.56 mmol (APTS)/g(sample)) can be effectively grafted within a very short time (2 h). The highly dispersed amine groups inside the channels can be facilely revealed by the location of in-situ coordinated Ag nanoparticles. Moreover, the amine-modified SBA-15 via the plasma treatment exhibited a better CO2 adsorption capacity (1.26 mmol/g) comparing with the traditional amine-modified SBA-15. Thus, our new approach may pave the way towards the rational modification and effective activation for porous materials, which would be meaningful for functionalization applications.

The surface inside the one-dimensional channels of mesoporous SBA-15 was effectively activated by DBD plasma treatment in O2 atmosphere, which promoted the amine modification with both large loading amount (2.56 mmol (APTS)/g(sample)) and high rate (within 2 h). The resulted material also showed a high CO2 adsorption capacity.Figure optionsDownload as PowerPoint slide