| Graphene prepared by the existing reductant had many extrinsic defects, andwould agglomerate easily. Hence, the performance of the graphene was severelycurtailed.In order to solve these problems, two kinds of new reductants are proposedin this paper, which are the mixed solution of alkali with thiourea dioxide and themixed solution of alkali with carbohydrazide. The new reductants and hydrazinehydrate were all used to prepare the graphene, and the reduction results of thesereductants would also be discussed in this paper.The SEM images showed that the graphene prepared by new reductants had amore uniform dispersion and would not agglomerate. The XRD maps showed that thecharacteristic peaks of the graphene replaced that of graphite oxide when using thosereductants, which means all of the reductants had enough reduction abilities. However,the characteristic peaks of the graphene prepared by the new reductants had higherintensities and smaller diffraction angles than that of the graphene prepared byhydrazine hydrate. It means that the graphene prepared by new reductants had abigger spacing between the carbon atom layers and higher degree of crystallinity thanthat of the graphene prepared by hydrazine hydrate. Therefore, the new reductantshad stronger reduction abilities than hydrazine hydrate. The Raman spectra showedthat ID\IGof the graphene prepared by the new reductants were smaller. It means thatthe new reductants had stronger reduction abilities. The graphene prepared by thenew reductants had stronger conductive abilities.Chemical reduction mechanism of graphite oxide by the new reductants wereproposed based on the experimental observations and the results of a variety ofcharacterization.The atmospheric pressure CVD method of preparing graphene films was alsoemployed in this paper. The Raman results was compared with that of the grapheneprepared by the new reductants, which showed that there were still a lot of room forquality improvement of the chemically reduced graphene. |
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