One-step synthesis of soy protein/graphene nanocomposites and their application in photothermal therapy

Bioinspired graphene-based metal oxide nanocomposites for photocatalytic and electrochemical performances: an updated review

Considering the rapidly increasing population, the development of new resources, skills, and devices that can provide safe potable water and clean energy remains one of the vital research topics for the scientific community. Owing to this, scientific community discovered such material for tackle this issue of environment benign, the new materials with graphene functionalized derivatives show significant advantages for application in multifunctional catalysis and energy storage systems. Herein, we highlight the recent methods reported for the preparation of graphene-based materials by focusing on the following aspects: (i) transformation of graphite/graphite oxide into graphene/graphene oxide via exfoliation and reduction; (ii) bioinspired fabrication or modification of graphene with various metal oxides and its applications in photocatalysis and storage systems. The kinetics of photocatalysis and the effects of different parameters (such as photocatalyst dose and charge-carrier scavengers) for the optimization of the degradation efficiency of organic dyes, phenol compounds, antibiotics, and pharmaceutical drugs are discussed. Further, we present a brief introduction on different graphene-based metal oxides and a systematic survey of the recently published research literature on electrode materials for lithium-ion batteries (LIBs), supercapacitors, and fuel cells. Subsequently, the power density, stability, pseudocapacitance charge/discharge process, capacity and electrochemical reaction mechanisms of intercalation, and conversion- and alloying-type anode materials are summarized in detail. Furthermore, we thoroughly distinguish the intrinsic differences among underpotential deposition, intercalation, and conventional pseudocapacitance of electrode materials. This review offers a meaningful reference for the construction and fabrication of graphene-based metal oxides as effective photocatalysts for photodegradation study and high-performance optimization of anode materials for LIBs, supercapacitors, and fuel cells.

Graphene oxide/mussel foot protein composites for high-strength and ultra-tough thin films

Graphene oxide (GO)-based composite materials have become widely popular in many applications due to the attractive properties of GO, such as high strength and high electrical conductivity at the nanoscale. Most current GO composites use organic polymer as the matrix material and thus, their synthesis suffers from the use of organic solvents or surfactants, which raise environmental and energy-consumption concerns. Inspired by mussel foot proteins (Mfp) secreted by the saltwater mussel, Mytilus galloprovincialis and by recent advances in microbial protein production, we developed an aqueous-based green synthesis strategy for preparing GO/Mfp film composites. These GO/Mfp films display high tensile strength (134–158 MPa), stretchability (~ 26% elongation), and high toughness (20–24 MJ/m³), beyond the capabilities of many existing GO composites. Renewable production of Mfp proteins and the facile fabrication process described provides a new avenue for composite material synthesis, while the unique combination of mechanical properties of GO/Mfp films will be attractive for a range of applications.

A Simple Flow Reactor for Continuous Synthesis of Biographene for Enzymology Studies

The unique properties of graphene make it an intriguing platform for the attachment and enhancement of biological molecules, but it has yet to achieve its full potential in terms of biological applications. Single-layer graphene is expensive, making alternatives to this material highly desired for applications that require high-quality graphene in large quantities. In this context, we report a simple, environmentally friendly, nonlabor-intensive method for the synthesis of colloidal graphene suspensions of 3-5 layers, stabilized by bovine serum albumin, in water. The method involves a flow reactor designed to continually yield high-quality graphene colloids, synthesized, purified, and optimized all in one setup. The flow reactor is able to produce colloidal graphene sheets on a multigram scale, and these colloids were characterized by Raman spectroscopy, electron microscopy, and zeta potential studies. The average size of the sheets is 0.16μm², each consisting of 3-5 layers of graphene with little or no sp³ defects. These graphene colloids stabilized by the protein were successfully used in protein kinetic studies as well as in surface plasmon resonance protein binding studies. The ease of synthesis of these high-quality graphene colloidal suspensions in water provides an exciting opportunity for biographene to be used on an industrial scale for electronic, thermal, and enzymology applications.

Dually functioned core-shell NaYF4:Er3+/Yb3+@NaYF4:Tm3+/Yb3+ nanoparticles as nano-calorifiers and nano-thermometers for advanced photothermal therapy

To realize photothermal therapy (PTT) of cancer/tumor both the photothermal conversion and temperature detection are required. Usually, the temperature detection in PTT needs complicated instruments, and the therapy process is out of temperature control in the present investigations. In this work, we attempt to develop a novel material for achieving both the photothermal conversion and temperature sensing and control at the same time. To this end, a core-shell structure with NaYF₄:Er³⁺/Yb³⁺ core for temperature detection and NaYF₄:Tm³⁺/Yb³⁺ shell for photothermal conversion was designed and prepared. The crystal structure and morphology of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, the temperature sensing properties for the NaYF₄:Er³⁺/Yb³⁺ and core-shell NaYF₄:Er³⁺/Yb³⁺@NaYF₄:Tm³⁺/Yb³⁺ nanoparticles were studied. It was found that the temperature sensing performance of the core-shell nanoparticles did not become worse due to coating of NaYF₄:Tm³⁺/Yb³⁺ shell. The photothermal conversion behaviors were examined in cyclohexane solution based on the temperature response, the NaYF₄:Er³⁺/Yb³⁺@NaYF₄:Tm³⁺/Yb³⁺ core-shell nanoparticles exhibited more effective photothermal conversion than that of NaYF₄:Er³⁺/Yb³⁺ nanoparticles, and a net temperature increment of about 7 °C was achieved by using the core-shell nanoparticles.