Scanning transmission electron microscopy analysis of Ge(O)/(graphitic carbon nitride) nanocomposite powder

• Main Authors: Masahiro Kawasaki, Kanganit Sompetch, Thapanee Sarakonsri, Makoto Shiojiri
• Format: Journal
• Published: 2018
• Subjects: Agricultural and Biological Sciences
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84945131747&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/44045
• Institution: Chiang Mai University

© 2015 Elsevier Inc. All rights reserved. Analytical electron microscopy has revealed the structure of particles that were synthesized by chemical reaction of GeO 2 with NaBH 4 in the basic solution including graphitic carbon nitride (g-C 3 N 4 ) powders. The g-C 3 N 4 was arranged by recrystallization of melamine at 600 °C under N 2 gas atmosphere. The samples were dried at 60 °C or 180 °C for 4 h. The g-C 3 N 4 was observed as lamellae of several ten nm or less in size and had an amorphous-like structure with a distorted lattice in an area as small as a few hundred pm in size. The reaction product was Ge(O) particles as fine as several nm in size and composed of Ge and O atoms. Most of the particles must be of GeO 2 - x with the amorphous-like structure that has also a distorted lattice in an area of a few hundred pm in size. In the sample dried at 60 °C, the particles were found to be dispersed in a wide area on the g-C 3 N 4 lamella. It is hard to recognize those particles in TEM images. The particles in the sample dried at 180 °C became larger and were easily observed as isolated lumps. Hence, these powders can be regarded as GeO 2 /g-C 3 N 4 or Ge/GeO 2 /g-C 3 N 4 nanocomposites, and expected to be applicable to anode materials for high energy Li-ion batteries due to Ge catalysis effect, accordingly.