Jacovone Raynara M S, Duarte Miguel, Soares Jaqueline J S, Faria Rubens N, Garcia Rafael H L, Angnes Lucio, Sakata Solange K
Nuclear and Energy Research Institute, National Commission of Nuclear Energy (IPEN/CNEN - SP), Av. Prof. Lineu Prestes 2242, 05508-000, São Paulo, SP, Brazil.
Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Av. Prof. Lineu Prestes 748, 05508-000, São Paulo, SP, Brazil.
Dalton Trans. 2025 Jul 8;54(27):10657-10666. doi: 10.1039/d4dt02211d.
This study introduces an environmentally friendly method for synthesizing reduced graphene oxide/nickel (rGO-Ni) nanocomposites for electrochemical applications using gamma irradiation. This approach eliminates the need for toxic chemical reductants and mitigates the generation of hazardous residues and undesirable by-products. The effect of the gamma irradiation dose on the size of nickel nanoparticles supported on graphene oxide was also investigated. The graphene oxide (GO) dispersion was subjected to gamma irradiation in the presence of the (Ni[(NH)]Cl) complex at doses of 20, 40 and 80 kGy and a dose rate of 10 kGy h. X-ray diffraction confirmed the formation of metallic Ni and the simultaneous reduction of graphene oxide (GO) induced by gamma irradiation, while X-ray photoelectron spectroscopy indicated the oxidation of the Ni metal on the GO surface. These findings were further corroborated by thermogravimetric analysis. To evaluate the electrochemical properties, screen-printed electrodes were modified with rGO and rGO-Ni. Cyclic voltammetry measurements in the presence of K[Fe(CN)] demonstrated reversible redox behavior for all samples. It is noteworthy that rGO-Ni/SPE exhibited a significant enhancement in the anodic peak currents () and electroactive surface area compared to the unmodified SPE. Furthermore, a direct correlation was observed between the value and the gamma radiation dose applied during the nanocomposite synthesis. These results point out the potential applications of rGO-Ni nanocomposites in electrochemical devices.
本研究介绍了一种利用伽马辐射合成用于电化学应用的还原氧化石墨烯/镍（rGO-Ni）纳米复合材料的环保方法。这种方法无需使用有毒化学还原剂，减少了有害残留物和不良副产物的产生。还研究了伽马辐射剂量对负载在氧化石墨烯上的镍纳米颗粒尺寸的影响。在（Ni[(NH)]Cl）络合物存在下，将氧化石墨烯（GO）分散体在20、40和80千戈瑞的剂量以及10千戈瑞/小时的剂量率下进行伽马辐射。X射线衍射证实了金属Ni的形成以及伽马辐射诱导的氧化石墨烯（GO）的同时还原，而X射线光电子能谱表明GO表面的Ni金属发生了氧化。热重分析进一步证实了这些发现。为了评估电化学性能，用rGO和rGO-Ni修饰丝网印刷电极。在K[Fe(CN)]存在下的循环伏安法测量表明所有样品都具有可逆的氧化还原行为。值得注意的是，与未修饰的SPE相比，rGO-Ni/SPE的阳极峰值电流（）和电活性表面积有显著提高。此外，在纳米复合材料合成过程中施加的伽马辐射剂量与值之间存在直接相关性。这些结果指出了rGO-Ni纳米复合材料在电化学器件中的潜在应用。
