Graphene, graphene oxide (GO), and their composites have been prominently utilized for wastewater purification because of their adsorption, oxidation, and catalytic properties. Graphene and GO and its composites naturally have significant pore volume, high conductivity, rich surface chemistry, and an exceptionally large aspect ratio which make it favorable for adsorption and catalysis of organic pollutants from wastewater. The sheet-like, resonating, polyaromatic π-system of graphene subsidiaries play a significant role in π–π interactions, hydrogen bonding, and/or electrostatic interactions with organic pollutants that include dyes, pharmaceutical waste, and agricultural and industrial effluents whose base structure consists of notably reactive unsaturated aromatic rings and oxygen-rich functional groups. The adsorption capacities of pollutants have been widely researched and catalogued by considering the adsorption isotherm (Langmuir, Freundlich, Temkin, DR model) they fit, the kinetic models (pseudo-fi...

Graphene and Graphene Oxide-Based Composites for Removal of Organic Pollutants: A Review

Facile hydrothermal synthesis of novel Fe-Cu layered double hydroxide/biochar nanocomposite with enhanced sonocatalytic activity for degradation of cefazolin sodium.

Recent developments of two-dimensional graphene-based composites in visible-light photocatalysis for eliminating persistent organic pollutants from wastewater

Powerful combination of 2D g-C3N4 and 2D nanomaterials for photocatalysis: Recent advances

2D/2D ultra-thin ZnIn2S4/protonated g-C3N4 nanocomposites (ZnIn2S4/pCN) are fabricated by electrostatic self-assembly strategy between negatively charged 2D ultra-thin ZnIn2S4 nanosheets and 2D protonated g-C3N4 nanosheets. The optimized ZnIn2S4/pCN (5:3) shows excellent photocatalytic activity toward H2 production (˜8601.16 μmol g−1 h−1) under visible light. In addition, ZnIn2S4/pCN also exhibits superior visible-light-driven photocatalytic tetracycline degradation efficiency, about ˜4.13 and ˜2.28 times higher than protonated g-C3N4 and ultra-thin ZnIn2S4, respectively. The optimal ZnIn2S4/pCN (5:3) also has good photostability. The excellent photocatalytic activity of ZnIn2S4/pCN can be attributed to the unique 2D/2D heterojunctions, which are obtained by electrostatic self-assembly. The intimate interfacial contact and larger contact areas promote the separation and migration of photogenerated carriers, which contribute to the improvement of photocatalytic activity and photostability. Our research on the 2D/2D nanocomposites provides a scalable solution for the research of efficient and active photocatalysts.

Constructing electrostatic self-assembled 2D/2D ultra-thin ZnIn2S4/protonated g-C3N4 heterojunctions for excellent photocatalytic performance under visible light

Magnetic NiAl layered doubled hydroxide (LDH)/Fe3O4–RGO composites were successfully synthesized via a simple hydrothermal route. The as-prepared samples were well characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The results showed that NiAl LDH nanoplatelets and Fe3O4 nanoparticles sized around 15 nm were uniformly anchored on the surface of graphene sheets. The NiAl LDH/Fe3O4–RGO25 photocatalyst was employed to degrade ciprofloxacin (CIP) in an aqueous solution under visible light irradiation. It exhibited enhanced photocatalytic activity compared to pure NiAl LDH, the degradation rate of the as-prepared NiAl LDH/Fe3O4–RGO25 was 1.5 and even 3 times faster than that of NiAl LDH/RGO25 and pure NiAl LDH, respectively. This enhancement of photocatalytic activity is attributed to the addition of graphene and Fe3O4 NPs, which both efficiently promote the separation of charge carriers and improve the optical absorption properties, synergistically facilitating the photocatalysis process. Furthermore, the NiAl LDH/Fe3O4–RGO25 photocatalyst was magnetically separable and exhibited stable catalytic activity, which is beneficial to its practical application.

Construction of magnetically separable NiAl LDH/Fe3O4–RGO nanocomposites with enhanced photocatalytic performance under visible light

A self-assembled 2D/2D-type protonated carbon nitride-modified graphene oxide nanocomposite with improved photocatalytic activity

Lithium niobate (LiNbO3, LN) is a kind of multifunctional crystal material. In this study, an optimum piezoelectric crystal cut (XZt/28°) with central resonance frequency of 150 kHz and stable electro-elastic...

High performance piezoelectric crystal cut designed in LiNbO3 for high temperature acoustic emission sensing application

We present a dual-channel resonance acoustic sensor based on a poly-(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) piezoelectric (PE) membrane which combines the Fabry–Pérot (FP) interference and PE effects. The deformation of circular thin films is indicated by interference and PE effects at the same time, and the noise level was decreased by real-time convolution of the two-way parallel signal. Studies reveal that at the film’s resonance frequency, the minimum detection limits for FP interference and the PE impact on acoustic waves are 2.61 and $15.64 ~\mu $ Pa/Hz1/2, respectively. The result of the convolution shows that the background noise has been reduced by 98.81% in relation to the PE signal and by 96.73% in relation to the FP interference signal, respectively. The signal-to-noise ratio (SNR) of the convolution is several times greater than the other two signals at 2 mPa.

High-Performance Acoustic Wave Sensor Based on PVDF-TrFE Membrane Combing the Piezoelectric and Fabry–Pérot Effects

Centimeter-sized high quality Ca2Nb2O7 crystals were successfully grown using the conventional Czochralski pulling method, and the relationship between the crystal structure and physical properties has been clearly explained.

Linfang Xie

Papers

Construction of magnetically separable NiAl LDH/Fe3O4–RGO nanocomposites with enhanced photocatalytic performance under visible light

A self-assembled 2D/2D-type protonated carbon nitride-modified graphene oxide nanocomposite with improved photocatalytic activity

High performance piezoelectric crystal cut designed in LiNbO3 for high temperature acoustic emission sensing application

High-Performance Acoustic Wave Sensor Based on PVDF-TrFE Membrane Combing the Piezoelectric and Fabry–Pérot Effects

Single crystal growth and piezoelectric features of the Ca2Nb2O7 crystal with orthorhombic symmetry