Possible pitfall in sample preparation for SEM analysis - A discussion of the paper “Fabrication of polycarboxylate/graphene oxide nanosheet composites by copolymerization for reinforcing and toughening cement composites” by Lv et al.

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• 作者：Hongzhi Cui^a ; Xiantong Yan^a ; Luping Tang^b ; Feng Xing^a ; ^{xingf@szu.edu.cn}
• 关键词：Graphene oxide ; Cement hydration ; Calcium carbonate ; Crystal morphology ; Sample preparation
• 刊名：Cement and Concrete Composites
• 出版年：2017
• 出版时间：March 2017
• 年：2017
• 卷：77
• 期：Complete
• 页码：81-85
• 全文大小：1615 K
• 卷排序：77

文摘

This paper presents a discussion of the paper published by Lv et al. in Cement and Concrete Composites, 2016, 66: 1–9. The discussion is mainly focused on whether or not graphene oxide (GO) nanosheets can regulate formation of flower-like cement hydration crystals. Lv et al. in their paper proposed a regulation mechanism stating that GO nanosheets can control ettringite (AFt), monosulfate (AFm) and calcium hydroxide (CH) to form the flower-like and polyhedron crystals, whilst our experimental results show that there might be a possible pitfall in sample preparation for SEM analysis. It is here suggested that the main chemical components of flower-like and polyhedron crystals are calcium carbonates, which are not the products from cement hydration but from carbonation of cementitious hydrates. It is therefore suggested that further study is needed to verify the regulation mechanism of GO on cement hydration crystals proposed by Lv et al. in the discussed paper.