화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.42, No.2, 1161-1169, 2017
A new approach on morphological features of synthesized graphene using the LPCVD technique applicable for fuel cell membrane
The one-atom-thick materials such as graphene, once thought to be impermeable, allow protons to pass through them. The result will be more efficient fuel cells and the simplification of the heretofore difficult process of separating hydrogen gas for use as fuel in fuel cells. In this research, a large scale graphene were synthesized by Low Pressure Chemical Vapor Deposition (LPCVD) technique. The effects of temperature growth on morphological features of the synthesized graphene on Cu foils were studied, using only Scanning Electron Microscopy (SEM) analysis. Raman spectrum was used to quantify defects and characteristics of synthesized graphene. Three peaks at similar to 1350, similar to 1580 and similar to 2750 cm(-1) related to the D band, G band and 2D band are shown from Raman analysis. The Mountains Map Premium software and the Gwyddion software were used for investigation on morphological features of synthesized graphene samples. The results show that the defects intensity in graphene decreased and the quality of synthesized graphene increased with increasing growth temperature. The grain size and producing the large area of graphene decreased and increased, respectively with the rise of temperature. At all temperatures growth, the multilayer graphene are grown on Cu substrates. The results of the motifs analysis shows that the synthesized graphene layers are made of oblong grains. On the surface of synthesized samples at 800 and 850 degrees C were dominant of valleys. Also, on the surface of synthesized samples at 900 and 1000 degrees C, the peaks were dominant. Thus, the surfaces of all synthesized samples were spiky and isotropic and have an oriented or periodical structure. All results of this work represent that the defects intensity, quality, grain size and uniformity of synthesized graphene could be controlled by only changing the temperature and keeping the other effective parameters constant. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.