It has been synthesized the graphene oxide-based hybrid ligands and their Cu(II), Co(II) and Ni(II) complexes. Firstly, GO was reacted with 3-(trimethoxysilyl)propylamine in ethanol and the obtained structure was treated with 2,6-diformyl-4-bromophenol and 2,6-diformyl-4-tert-butylphenol in order to obtain the hybrid ligands HL¹ and HL². The synthesized hybrid ligands and their metal complexes have been and characterized by using FTIR, UV–vis., XRD, EDX, SEM, TEM, cyclic voltammetry, TG/DTA and ICP-OES techniques. Catalytic activities of Cu(II), Co(II) and Ni(II) complexes of the synthesized ligands have been investigated in the oxidation of 2-methyl naphthalene (2MN) to 2-methyl-1,4-naphthoquinone (vitamin K₃). The chemosensing behaviours of the hybrid ligands were also researched by using UV–vis. technique upon addition of various metal ions such as Na(I), K(I), Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Zn(II), Al(III), Cr(III), Fe(III), and Mn(II) in (1:5 V) ratio in MeOH. The UV–vis. spectra of free hybrid materials show one absorption band at 257 nm possibly due to π–π* transitions in hybrid ligands. While added the metal cations on the ligand dispersions as Cu(II) and Fe(III) (0.1 mM) (1:5 V) ratios in MeOH, a new absorption bands were appeared at different regions in 275–325, 300–375 nm, respectively, because of the complexation between the hybrid materials and the metal ions.

Graphic Abstract

中文翻译：

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石墨烯基杂化配体及其金属配合物的合成与表征：化学传感器和催化性能的研究

已经合成了基于氧化石墨烯的杂化配体及其Cu（II），Co（II）和Ni（II）配合物。首先，使GO与3-（三甲氧基甲硅烷基）丙胺在乙醇中反应，并将所得结构用2,6-二甲酰基-4-溴苯酚和2,6-二甲酰基-4-叔丁基苯酚处理以获得杂配体HL ¹和HL ²。合成的杂配体及其金属配合物已通过FTIR，UV-vis。，XRD，EDX，SEM，TEM，循环伏安，TG / DTA和ICP-OES技术进行了表征。在2-甲基萘（2MN）氧化为2-甲基-1,4-萘醌（维生素K ₃）中，研究了合成配体的Cu（II），Co（II）和Ni（II）配合物的催化活性。）。杂化配体的化学传感行为也通过使用紫外可见光谱进行了研究。添加各种金属离子（例如Na（I），K（I），Cd（II），Co（II），Cu（II），Hg（II），Ni（II），Zn（II），Al （III），Cr（III），Fe（III）和Mn（II）在MeOH中的比例为（1：5 V）。紫外可见 游离杂化材料的光谱在257 nm处显示一个吸收带，这可能是由于杂化配体中的π–π *跃迁所致​​。当在配体分散体中以Cu（II）和Fe（III）（0.1 mM）（1：5 V）的比例添加金属阳离子时，在275-325、300-375的不同区域出现了一个新的吸收带分别由于杂化材料和金属离子之间的络合而导致的纳米级。

图形摘要