@article{scholars17156, year = {2022}, journal = {Journal of Colloid and Interface Science}, publisher = {Academic Press Inc.}, pages = {1131--1141}, volume = {607}, note = {cited By 4}, doi = {10.1016/j.jcis.2021.09.042}, title = {Facile asymmetric modification of graphene nanosheets using {\^I}?-carrageenan as a green template}, keywords = {Hydrogels; Hydrogen bonds; Nanosheets, Amphiphilic graphene oxide; Amphiphilics; Asymmetric modifications; Carrageenans; Exposed surfaces; Hydrogel matrix; Janus particles; Porous hydrogels; Property; {\^I}?-carrageenan, Graphene, graphene oxide; hydrogel; nanosheet; carrageenan; graphite, Article; chemical interaction; chemical modification; controlled study; emulsion; Fourier transform spectroscopy; heat tolerance; hydrogen bond; hydrophobicity; pH; porosity; scanning electron microscopy; surface property; synthesis; X ray diffraction; X ray photoemission spectroscopy; hydrogel, Carrageenan; Graphite; Hydrogels; Hydrogen Bonding}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85115747486&doi=10.1016\%2fj.jcis.2021.09.042&partnerID=40&md5=49da1f832c2cfb31bbb18f2d6d1041ec}, abstract = {The synthesis of Janus nanosheets using {\^I}?-carrageenan ({\^I}?-Ca) as a green template endows a greener and more straightforward method compared to traditional approaches of using wax template. We hypothesize that the hydrogen bonding interaction between {\^I}?-Ca and graphene oxide (GO) allows partial masking of GO's single facet, paving the way for the asymmetric modification of the exposed surface. GO is first encapsulated within the porous hydrogel matrix formed by {\^I}?-Ca to isolate one of the facets. The exposed surface was then selectively hydrophobized to produce an amphiphilic asymmetrically modified graphene oxide (AMGO). The properties of AMGO synthesized under different {\^I}?-Ca/GO ratios were studied. The {\^I}?-Ca/GO interactions and the properties of GO and AMGO were investigated and characterized. AMGO was successfully produced with a yield of 90.37 under optimized synthesis conditions. The separation of {\^I}?-Ca and AMGO was conducted without organic solvents, and the {\^I}?-Ca could be subsequently recovered. Furthermore, the porous hydrogel matrix formed by {\^I}?-Ca and GO exhibited excellent shape-retaining properties with high thermal tolerance of up to 50 {\^A}oC. Given these benefits, this newly developed method endows sustainability and open the possibility of formulating more flexible material synthesis protocols. {\^A}{\copyright} 2021 Elsevier Inc.}, issn = {00219797}, author = {Tiong, A. C. Y. and Tan, I. S. and Foo, H. C. Y. and Lam, M. K. and Mahmud, H. B. and Lee, K. T.} }