Self‐Assembled Graphene Hydrogel Composites for Selective Dye Removal,Advanced Sustainable Systems

当前位置： X-MOL 学术 › Adv. Sust. Syst. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Self‐Assembled Graphene Hydrogel Composites for Selective Dye Removal
Advanced Sustainable Systems ( IF 6.5 ) Pub Date : 2020-06-28 , DOI: 10.1002/adsu.202000055
Azza Al Subhi ₁ , Mohammad Valizadeh Kiamahalleh ₂ , Maryam Firouzi ₃ , Fereshteh Yousefi ₄ , Htet Htet Kyaw ₅ , Mohammed Al Abri _{5,

6} , Amin Firouzi _{1,

7} , Meisam Valizadeh Kiamahalleh _{1,

8}

Affiliation

Graphene‐based hydrogels are known as promising amphiphilic agents for water uptake and selective organic contaminant removal. However, it is a challenge to prevent graphene sheet restacking during the gelation as this factor significantly influences the adsorption behavior of organic contaminant. A porous reduced graphene oxide‐starch hydrogel (rGOSH) with enhanced pore size is produced by a simple one‐step method through starch‐directed self‐assembly of graphene sheets. This hydrogel demonstrated to be a promising candidate for the selective removal of organic dye molecules, where positive and neutral dyes are adsorbed, and the negative one is repelled. In particular, the hydrogel prepared with incorporation of starch between the graphene sheets, adsorbs positively charged dye ≈75% more than reduced graphene oxide hydrogel, due to better diffusion into larger pore size and strong electrostatic interaction with negatively charged oxygen groups. Furthermore, the Langmuir isotherm model and kinetic studies for dyes adsorption onto rGOSH reveal that the adsorption mechanisms are dominantly chemisorption within the porous hydrogel structure since the experimental data can be well fitted to the pseudo‐second‐order dynamic equation with the highest adsorption capacity (1106.950 µg g⁻¹) and kinetic (1.957E‐05 g µg⁻¹ min^−0.5) toward the positively charged dye.

中文翻译：

自组装石墨烯水凝胶复合材料用于选择性去除染料

基于石墨烯的水凝胶被认为是有希望的两亲剂，可用于水吸收和选择性去除有机污染物。但是，防止石墨烯片在胶凝过程中重新堆积是一个挑战，因为该因素会显着影响有机污染物的吸附行为。通过淀粉导向的石墨烯片自组装，通过简单的一步法即可制得孔径增大的多孔还原型氧化石墨烯-淀粉水凝胶（rGOSH）。该水凝胶被证明是选择性去除有机染料分子的有前途的候选者，其中吸附了正性和中性染料，而负性被排斥。特别是，在石墨烯片之间掺入淀粉而制得的水凝胶比还原的氧化石墨烯水凝胶吸收的正电荷染料多出约75％，由于能够更好地扩散到更大的孔径中以及与带负电荷的氧基团产生强静电相互作用。此外，Langmuir等温模型和染料在rGOSH上的吸附动力学研究表明，吸附机理主要是在多孔水凝胶结构内进行化学吸附，因为实验数据可以很好地拟合到具有最高吸附能力的拟二级动力学方程（ 1106.950微克g^-1）和动力学（1.957E-05 g µg ^-1 min ^-0.5）。

更新日期：2020-06-28

点击分享查看原文

点击收藏

阅读更多本刊最新论文