One-step synthesis of mesoporous silica�?�graphene composites by simultaneous hydrothermal coupling and reduction of graphene oxide

[摘要] Silicaâ€�?�graphene oxide composites were synthesized by hydrothermal method with simultaneous functionalization and reduction of graphene oxide (GO) in the presence of mesoporous silica. Two types of silica were used in the study, mesoporous synthetic silica (MSU-F) synthesized by sol-gel method and mesoporous mineral silica (meso-celite) from pseudomorphic synthesis. The infrared spectra of the composites showed the disappearance of the carboxyl peak at 1735 cm^-1 which could be due to the reduction of the â€�?�COOH group. The enhancement of the band at 1385 cm^-1 is attributed to the vibration of the Siâ€�?�Oâ€�?�C=O moiety formed by reaction of the â€�?�COOH group of GO and the silanol (Siâ€�?�OH) of silica. The Raman spectra of the composites show a diminished intensity ratio of D to G band indicating that GO was reduced to graphene sheets. The TEM images demonstrate the coupling of silica to GO surface revealing dense loading of silica on GO in planar structure.

[学科分类] 材料工程

[关键词] Graphene;graphene oxide;mineral silica;silica;mesoporous silica;hydrothermal reduction.