NiCo2S4/tryptophan-functionalized graphene quantum dot nanohybrids for high-performance supercapacitors

2017 ◽  
Vol 41 (3) ◽  
pp. 1110-1118 ◽  
Author(s):  
Huiying Wang ◽  
Yongqiang Yang ◽  
Xiaoyan Zhou ◽  
Ruiyi Li ◽  
Zaijun Li

This paper reports a facile synthesis of NiCo2S4via a one-step hydrothermal reaction and its hybrid with tryptophan-functionalized graphene quantum dots. The nanohybrid electrode exhibits significantly enhanced electrochemical performance for supercapacitors.

2019 ◽  
Vol 3 (9) ◽  
pp. 2499-2508 ◽  
Author(s):  
Maiwen Zhang ◽  
Wenwen Liu ◽  
Ruilin Liang ◽  
Ricky Tjandra ◽  
Aiping Yu

A method that adapts graphene quantum dots (GQDs) as structural inducing agents to tune the morphology of MnCo2O4.5/GQDs composites is developed, and utilized to enhance their electrochemical performance for supercapacitor applications.


RSC Advances ◽  
2014 ◽  
Vol 4 (99) ◽  
pp. 55709-55715 ◽  
Author(s):  
Takashi Ogi ◽  
Hideharu Iwasaki ◽  
Kana Aishima ◽  
Ferry Iskandar ◽  
Wei-Ning Wang ◽  
...  

A facile, economic and environmentally friendly one-step approach for the preparation of highly luminescent graphene quantum dots (GQDs) was developed using a hydrothermal reaction between citric acid and urea.


2021 ◽  
Author(s):  
Xu Dan ◽  
Ruiyi Li ◽  
Qinsheng Wang ◽  
Yongqiang Yang ◽  
Haiyan Zhu ◽  
...  

The paper reports the synthesis of nickel-silver-graphene quantum dot-graphene hybrid. Histidine-functionalized graphene quantum dots (His-GQDs) were bonded to graphene oxide (GO) and then combined with Ni2+ and Ag+ to form...


Nanomaterials ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 104 ◽  
Author(s):  
Rabeb El-Hnayn ◽  
Laetitia Canabady-Rochelle ◽  
Christophe Desmarets ◽  
Lavinia Balan ◽  
Hervé Rinnert ◽  
...  

2,2’-(Ethylenedioxy)bis(ethylamine)-functionalized graphene quantum dots (GQDs) were prepared under mild conditions from graphene oxide (GO) via oxidative fragmentation. The as-prepared GQDs have an average diameter of ca. 4 nm, possess good colloidal stability, and emit strong green-yellow light with a photoluminescence (PL) quantum yield of 22% upon excitation at 375 nm. We also demonstrated that the GQDs exhibit high photostability and the PL intensity is poorly affected while tuning the pH from 1 to 8. Finally, GQDs can be used to chelate Fe(II) and Cu(II) cations, scavenge radicals, and reduce Fe(III) into Fe(II). These chelating and reducing properties that associate to the low cytotoxicity of GQDs show that these nanoparticles are of high interest as antioxidants for health applications.


2016 ◽  
Vol 4 (27) ◽  
pp. 10414-10418 ◽  
Author(s):  
Ying Ma ◽  
Yulong Jia ◽  
Lina Wang ◽  
Min Yang ◽  
Yingpu Bi ◽  
...  

Three-dimensional MoO2–G flower-like nanostructures were synthesized through a facile hydrothermal reaction and showed significantly improved specific capacitance, good rate capability and cycling stability.


2015 ◽  
Vol 3 (21) ◽  
pp. 11199-11202 ◽  
Author(s):  
Ning Lin ◽  
Liangbiao Wang ◽  
Jianbin Zhou ◽  
Jie Zhou ◽  
Ying Han ◽  
...  

High-performance Si/Ge anodes are prepared through a one-step solid-state metathesis reaction between Mg2Si and GeO2 for the first time.


RSC Advances ◽  
2018 ◽  
Vol 8 (52) ◽  
pp. 29939-29946 ◽  
Author(s):  
Beatriz Fresco-Cala ◽  
M. Laura Soriano ◽  
Alice Sciortino ◽  
Marco Cannas ◽  
Fabrizio Messina ◽  
...  

Graphene quantum dot (GQDs) assemblies from a one-step microwave reaction as bifunctional materials in remediation of triazines.


NANO ◽  
2016 ◽  
Vol 11 (12) ◽  
pp. 1650138 ◽  
Author(s):  
Yinhua Jin ◽  
Hongyi Qin ◽  
Jang Ah Kim ◽  
Sun-Young Kim ◽  
Hyeong-U Kim ◽  
...  

The unique properties of graphene quantum dots (GQDs) make them interesting candidate materials for innovative applications. Herein, we report a facile method to synthesize amino-functionalized graphene quantum dots (AF-GQDs) by a hydrothermal reaction. Graphene oxide (GO) was synthesized by Hummer’s method where ultra-small GO sheets were obtained by a prolonged oxidation process followed by sonication using an ultrasonic probe. Subsequently, graphene hydrogel (GH) was also obtained by a hydrothermal synthesis method. Proper care was taken during synthesis to avoid contamination from water soluble impurities, which are present in the precursor, GO solution. Following the treatment of GH in ammonia, ultra-small amino-functionalized graphene fragments (AF-GQDs) were formed, which detached from the GH to eventually disperse evenly in the water without agglomerating. This modified synthesis process enables the formation of high-purity AF-GQDs (99.14%) while avoiding time-consuming synthesis procedures. Our finding shows that AF-GQDs with sizes less than 5[Formula: see text]nm were well dispersed. A strong photoluminescence (PL) emission at [Formula: see text]410[Formula: see text]nm with 10% PL quantum yield was also observed. These AF-GQDs can be used in many bio applications in view of their low cytotoxicity and strong fluorescence that can be applied to cell imaging.


Sign in / Sign up

Export Citation Format

Share Document