122nd General Meeting of the KCS

Type Oral Presentation
Area Oral Presentation of Young Material Chemists
Room No. Room 322
Time THU 10:31-:
Code MAT.O-14
Subject Soft Chemical Route to Single Molecular Layered g-carbon nitride
Authors Huiyan Piao, Goeun Choi, Jin-ho Choy*
Department of Chemistry and Nano Science, Ewha Womans University, Korea
Abstract Graphitic carbon nitride (g-C3N4) has received a great attention not only due to its high chemical and thermal stability, but also its various applications like visible light harvesting photocatalyst, metal-free catalyst and reactive template in nitridation reaction. In addition, its single sheet has attracted great research attention, due to the fact that its single layered molecular structure is very similar to the graphene except tri-angular hole, giving rise to a remarkable enhancement of specific surface area. It is, however, a challenging task to prepare chemically well-defined single sheet of g-C3N4. In the present study, single layered g-C3N4 could be obtained from the bottom-up process based on the polycondensation reaction of cyanamide as a g-C3N4 precursor, in the interlayer space of 2D aluminosilicate as a 2D nanoreactor (Mica). The single layered g-C3N4 can finally be separated from thus prepared g-C3N4-Mica nanohybrid, since the aluminosilicate matrix can be dissolvable under an acidic condition. Each reaction step to single layered g-C3N4 from cyanamide confined in 2D nanoreactor was monitored by X-ray diffraction, FT-IR, UV-Vis, XPS and EELS analyses. According to the AFM analysis, the average topographic height of as-prepared single layered sheet was determined to be around 0.5 nm, which is almost equal to the thickness of a single layer g-C3N4. Finally, the crystal structure of single layered g-C3N4 in an atomic level was further confirmed by low dose Cs-corrected high-resolution transmission electron microscopy (Cs-HRTEM). The single layered sheet exhibited an ordered structure of well-defined hexagonal symmetry with cavity formed by in-plane encirclement of three adjacent heptazine units. It is, therefore, concluded that the present soft chemical route to g-C3N4 single sheet can give rise to atomically well-defined phase consistent made of tri-s-triazine building blocks.
E-mail phy1216@hotmail.com