Strategies for Incorporating Graphene Oxides and Quantum Dots into Photoresponsive Azobenzenes for Photonics and Thermal Applications

Graphene represents a new generation of materials which exhibit unique physicochemical properties such as high electron mobility, tunable optics, a large surface to volume ratio, and robust mechanical strength. These properties make graphene an ideal candidate for various optoelectronic, photonics, and sensing applications. In recent years, numerous efforts have been focused on azobenzene polymers (AZO-polymers) as photochromic molecular switches and thermal sensors because of their light-induced conformations and surface-relief structures. However, these polymers often exhibit drawbacks such as low photon storage lifetime and energy density. Additionally, AZO-polymers tend to aggregate even at moderate doping levels, which is detrimental to their optical response. These issues can be alleviated by incorporating graphene derivatives (GDs) into AZO-polymers to form orderly arranged molecules. GDs such as graphene oxide (GO), reduced graphene oxide (RGO), and graphene quantum dots (GQDs) can modulate the optical response, energy density, and photon storage capacity of these composites. Moreover, they have the potential to prevent aggregation and increase the mechanical strength of the azobenzene complexes. This review article summarizes and assesses literature on various strategies that may be used to incorporate GDs into azobenzene complexes. The review begins with a detailed analysis of structures and properties of GDs and azobenzene complexes. Then, important aspects of GD-azobenzene composites are discussed, including: (1) synthesis methods for GD-azobenzene composites, (2) structure and physicochemical properties of GD-azobenzene composites, (3) characterization techniques employed to analyze GD-azobenzene composites, and most importantly, (4) applications of these composites in various photonics and thermal devices. Finally, a conclusion and future scope are given to discuss remaining challenges facing GD-azobenzene composites in functional science engineering.

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Graphene- and Graphene Oxide-Based Nanocomposite Platforms for Electrochemical Biosensing Applications

International Journal of Molecular Sciences ◽

10.3390/ijms20122975 ◽

2019 ◽

Vol 20 (12) ◽

pp. 2975 ◽

Cited By ~ 25

Author(s):

Madasamy Thangamuthu ◽

Kuan Yu Hsieh ◽

Priyank V. Kumar ◽

Guan-Yu Chen

Keyword(s):

Quantum Dots ◽

Graphene Oxide ◽

High Surface ◽

High Surface Area ◽

Cell Capture ◽

Structure Property ◽

Structure Property Relationships ◽

Electrochemical Biosensing ◽

Graphene Derivatives ◽

Enzymatic Biosensors

Graphene and its derivatives such as graphene oxide (GO) and reduced GO (rGO) offer excellent electrical, mechanical and electrochemical properties. Further, due to the presence of high surface area, and a rich oxygen and defect framework, they are able to form nanocomposites with metal/semiconductor nanoparticles, metal oxides, quantum dots and polymers. Such nanocomposites are becoming increasingly useful as electrochemical biosensing platforms. In this review, we present a brief introduction on the aforementioned graphene derivatives, and discuss their synthetic strategies and structure–property relationships important for biosensing. We then highlight different nanocomposite platforms that have been developed for electrochemical biosensing, introducing enzymatic biosensors, followed by non-enzymatic biosensors and immunosensors. Additionally, we briefly discuss their role in the emerging field of biomedical cell capture. Finally, a brief outlook on these topics is presented.

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Nonlinear optical response of some Graphene oxide and Graphene fluoride derivatives

Optofluidics Microfluidics and Nanofluidics ◽

10.1515/optof-2016-0009 ◽

2016 ◽

Vol 3 (1) ◽

Cited By ~ 7

Author(s):

Nikolaos Liaros ◽

Ioannis Orfanos ◽

Ioannis Papadakis ◽

Stelios Couris

Keyword(s):

Graphene Oxide ◽

Nonlinear Absorption ◽

Nonlinear Optical ◽

Nonlinear Refraction ◽

Optical Response ◽

Nonlinear Optical Response ◽

Third Order ◽

Nonlinear Properties ◽

Graphene Derivatives ◽

532 Nm

AbstractThe nonlinear optical properties of two graphene derivatives, graphene oxide and graphene fluoride, are investigated by means of the Z-scan technique employing 35 ps and 4 ns, visible (532 nm) laser excitation. Both derivatives were found to exhibit significant third-order nonlinear optical response at both excitation regimes, with the nonlinear absorption being relatively stronger and concealing the presence of nonlinear refraction under ns excitation, while ps excitation reveals the presence of both nonlinear absorption and refraction. Both nonlinear properties are of great interest for several photonics, opto-fluidics, opto-electronics and nanotechnology applications.

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Detection of Heavy Metals in Water Using Graphene Oxide Quantum Dots: An Experimental and Theoretical Study

Molecules ◽

10.3390/molecules26185519 ◽

2021 ◽

Vol 26 (18) ◽

pp. 5519

Author(s):

Lorenzo Gontrani ◽

Olivia Pulci ◽

Marilena Carbone ◽

Roberto Pizzoferrato ◽

Paolo Prosposito

Keyword(s):

Heavy Metals ◽

Quantum Dots ◽

Graphene Oxide ◽

Ab Initio Calculations ◽

Ab Initio ◽

Theoretical Study ◽

Graphene Quantum Dots ◽

Emission Spectra ◽

Optical Response ◽

Graphene Oxide Quantum Dots

In this work, we investigate by ab initio calculations and optical experiments the sensitivity of graphene quantum dots in their use as devices to measure the presence, and concentration, of heavy metals in water. We demonstrate that the quenching or enhancement in the optical response (absorption, emission) depends on the metallic ion considered. In particular, two cases of opposite behaviour are considered in detail: Cd2+, where we observe an increase in the emission optical response for increasing concentration, and Pb2+ whose emission spectra, vice versa, are quenched along the concentration rise. The experimental trends reported comply nicely with the different hydration patterns suggested by the models that are also capable of reproducing the minor quenching/enhancing effects observed in other ions. We envisage that quantum dots of graphene may be routinely used as cheap detectors to measure the degree of poisoning ions in water.

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Ti3C2Tx Nanosheets/Ti3C2Tx Quantum Dots/RGO (Reduced Graphene Oxide) Fibers for an All-Solid-State Asymmetric Supercapacitor with High Volume Energy Density and Good Flexibility

ACS Applied Materials & Interfaces ◽

10.1021/acsami.9b21874 ◽

2020 ◽

Vol 12 (10) ◽

pp. 11833-11842 ◽

Cited By ~ 4

Author(s):

Xu Zhou ◽

Yi Qin ◽

Xuexia He ◽

Qi Li ◽

Jie Sun ◽

...

Keyword(s):

Quantum Dots ◽

Graphene Oxide ◽

Solid State ◽

Energy Density ◽

Reduced Graphene Oxide ◽

High Volume ◽

Asymmetric Supercapacitor ◽

Reduced Graphene ◽

Volume Energy

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Application of Functionalized Graphene Oxide Based Biosensors for Health Monitoring: Simple Graphene Derivatives to 3D Printed Platforms

Biosensors ◽

10.3390/bios11100384 ◽

2021 ◽

Vol 11 (10) ◽

pp. 384

Author(s):

Agnivo Gosai ◽

Kamil Reza Khondakar ◽

Xiao Ma ◽

Md. Azahar Ali

Keyword(s):

Graphene Oxide ◽

Environmental Monitoring ◽

Synthesis Process ◽

High Electron ◽

Functionalized Graphene Oxide ◽

Point Of Use ◽

Graphene Derivatives ◽

Key Factor ◽

Manufacturing Techniques ◽

Electron Transfer Properties

Biosensors hold great potential for revolutionizing personalized medicine and environmental monitoring. Their construction is the key factor which depends on either manufacturing techniques or robust sensing materials to improve efficacy of the device. Functional graphene is an attractive choice for transducing material due to its various advantages in interfacing with biorecognition elements. Graphene and its derivatives such as graphene oxide (GO) are thus being used extensively for biosensors for monitoring of diseases. In addition, graphene can be patterned to a variety of structures and is incorporated into biosensor devices such as microfluidic devices and electrochemical and plasmonic sensors. Among biosensing materials, GO is gaining much attention due to its easy synthesis process and patternable features, high functionality, and high electron transfer properties with a large surface area leading to sensitive point-of-use applications. Considering demand and recent challenges, this perspective review is an attempt to describe state-of-the-art biosensors based on functional graphene. Special emphasis is given to elucidating the mechanism of sensing while discussing different applications. Further, we describe the future prospects of functional GO-based biosensors for health care and environmental monitoring with a focus on additive manufacturing such as 3D printing.

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Fluorescence and Sensing Applications of Graphene Oxide and Graphene Quantum Dots: A Review

Chemistry - An Asian Journal ◽

10.1002/asia.201700814 ◽

2017 ◽

Vol 12 (18) ◽

pp. 2343-2353 ◽

Cited By ~ 101

Author(s):

Peng Zheng ◽

Nianqiang Wu

Keyword(s):

Quantum Dots ◽

Graphene Oxide ◽

Graphene Quantum Dots ◽

Sensing Applications

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Highly Luminescent Ternary Nanocomposite of Polyaniline, Silver Nanoparticles and Graphene Oxide Quantum Dots

Scientific Reports ◽

10.1038/s41598-019-53584-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 8

Author(s):

Azza Shokry ◽

M. M. A. Khalil ◽

Hesham Ibrahim ◽

Moataz Soliman ◽

Shaker Ebrahim

Keyword(s):

Quantum Dots ◽

Silver Nanoparticles ◽

Graphene Oxide ◽

Chemical Reduction ◽

Oxidative Polymerization ◽

Sensing Applications ◽

Ternary Nanocomposite ◽

Average Size ◽

Graphene Oxide Quantum Dots ◽

20 Nm

AbstractQuantum dots (QDs) with photostability show a potential application in optical sensing and biological imaging. In this work, ternary nanocomposite (NC) of high fluorescent polyaniline (PANI)/2-acrylamido-2-methylpropanesulfonic acid (AMPSA) capped silver nanoparticles (NPs)/graphene oxide quantum dots (PANI/Ag (AMPSA)/GO QDs) have been synthesized by in situ chemical oxidative polymerization of aniline in the presence of Ag (AMPSA) NPs and GO QDs. Ag (AMPSA) NPs and GO QDs were prepared by AgNO3 chemical reduction and glucose carbonization methods, respectively. The prepared materials were characterized using UV-visible, Fourier transform infrared (FTIR), photoluminescence and Raman spectroscopies, X-Ray diffractometer (XRD) and high- resolution transmission electron microscopy (HRTEM). HRTEM micrographs confirmed the preparation of GO QDs with an average size of 15 nm and Ag (AMPSA) NPs with an average size of 20 nm. PANI/Ag (AMPSA)/GO QDs NC showed high and stable emission peak at 348 nm. This PANI/Ag (AMPSA)/GO QDs NC can emerge as a new class of fluorescence materials that could be suitable for practical sensing applications.

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Functionalized Nano-graphene Oxide as Multi-modal Clinic for Effective Drug Delivery

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2017.10.4.3 ◽

2017 ◽

Vol 10 (4) ◽

pp. 3768-3771

Author(s):

Soumitra Satapathi ◽

Rutusmita Mishra ◽

Manisha Chatterjee ◽

Partha Roy ◽

Somesh Mohapatra

Keyword(s):

Drug Delivery ◽

Graphene Oxide ◽

Cancer Cell ◽

High Surface ◽

High Surface Area ◽

Cancer Cell Line ◽

Xrd Analysis ◽

Graphene Derivatives ◽

Nano Graphene

Nano-materials based drug delivery modalities to specific organs and tissues has become one of the critical endeavors in pharmaceutical research. Recently, two-dimensional graphene has elicited considerable research interest because of its potential application in drug delivery systems. Here we report, the drug delivery applications of PEGylated nano-graphene oxide (nGO-PEG), complexed with a multiphoton active and anti-cancerous diarylheptanoid drug curcumin. Specifically, graphene-derivatives were used as nanovectors for the delivery of the hydrophobic anticancer drug curcumin due to its high surface area and easy surface functionalization. nGO was synthesized by modified Hummer’s method and confirmed by XRD analysis. The formation of nGO, nGO-PEG and nGO-PEG-Curcumin complex were monitored through UV-vis, IR spectroscopy. MTT assay and AO/EB staining found that nGO-PEG-Curcumin complex afforded highly potent cancer cell killing in vitro with a human breast cancer cell line MCF7.

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