In this paper, we have reported that well-defined graphene oxide (GO) enwrapped Ag/AgX (X = Br, Cl) nanocomposites, which are composed of Ag/AgX nanoparticles and gauze-like GO nanosheets, could be facilely fabricated via a water/oil system. We have shown that thus-synthesized GO-based hybrid nanocomposites could be used as a stable plasmonic photocatalyst for the photodegradation of methyl orange (MO) pollutant under visible-light irradiation. Compared with the corresponding bare Ag/AgX nanospecies, the GO-involved nanocomposites (Ag/AgX/GO) display distinctly enhanced photocatalytic activities. The hybridization of Ag/AgX with GO nanosheets causes the nice adsorptive capacity of Ag/AgX/GO to MO molecules, the smaller size of the Ag/AgX nanoparticles in Ag/AgX/GO, the facilitated charge transfer, and the suppressed recombination of electron-hole pairs in Ag/AgX/GO. It is suggested that these multifactors, resulting from the hybridization of GO, contribute to the enhanced photocatalytic performance observed from Ag/AgX/GO. The investigation likely opens up new possibilities for the development of original yet highly efficient and stable GO-based plasmonic photocatalysts that utilize visible light as an energy source.

Organic field-effect transistors (OFETs) are one of the key components of modern organic electronics. While the past several decades have witnessed huge successes in high-performance OFETs, their sophisticated functionalization with regard to the responses towards external stimulations has also aroused increasing attention and become an important field of general concern. This is promoted by the inherent merits of organic semiconductors, including considerable variety in molecular design, low cost, light weight, mechanical flexibility, and solution processability, as well as by the intrinsic advantages of OFETs including multiparameter accessibility and ease of large-scale manufacturing, which provide OFETs with great potential as portable yet reliable sensors offering high sensitivity, selectivity, and expeditious responses. With special emphases on the works achieved since 2009, this tutorial review focuses on OFET-based gas sensors. The working principles of this type of gas sensors are discussed in detail, the state-of-the-art protocols developed for high-performance gas sensing are highlighted, and the advanced gas discrimination systems in terms of sensory arrays of OFETs are also introduced. This tutorial review intends to provide readers with a deep understanding for the future design of high-quality OFET gas sensors for potential uses.

We have shown that various porphyrin-containing nanostructures can be easily synthesized by a surfactant-assisted self-assembly (SAS) method, where an oil/aqueous medium is employed. When a chloroform solution of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP) was added dropwise into cetyltrimethylammonium bromide (CTAB) aqueous solution, diverse ZnTPyP-based nanostructures, including hollow nanospheres, solid nanospheres, nanotubes, nanorods, and nanofibers, were successfully assembled. Depending on the aging time, when a low-concentration CTAB aqueous solution was employed, hollow nanospheres or nanotubes were produced. In contrast, either solid nanospheres or nanorods were obtained by using a CTAB aqueous solution in moderate concentration. Moreover, solid nanospheres or nanofibers were produced, when a high-concentration CTAB aqueous solution was used. We have further shown that the nanorods can be hierarchically organized into a regular nanoarray on silicon substrates over a large area, while the other nanostructures cannot. Interestingly, the nanorods displayed distinct supramolecular chirality although the employed ZnTPyP is achiral. On the basis of the information obtained from scanning electron microscopy, high-resolution transmission electron microscopy, fast Fourier transformation, energy-dispersive X-ray spectroscopy, X-ray diffraction, and UV-vis and circular dichroism spectra, a tentative explanation has been proposed. Our investigation suggests that the SAS method via an oil/aqueous medium is an efficient way to synthesize organic nanostructures in a controlled manner, and that such nanostructures can show different chiroptical and assembly properties.

In this article, we report that Ag/AgBr nanostructures and the corresponding graphene oxide (GO) hybridized nanocomposite, Ag/AgBr/GO, could be facilely synthesized by means of a surfactant-assisted assembly protocol, where an oil/water microemulsion is used as the synthesis medium. We show that thus-produced nanomaterials could be used as highly efficient and stable plasmonic photocatalysts for the photodegradation of methyl orange (MO) pollutant under sunlight irradiation. Compared with the bare Ag/AgBr nanospecies, Ag/AgBr/GO displays distinctly enhanced photocatalytic activity. More importantly, the as-prepared nanostructures exhibit higher photocatalytic activity than that of the corresponding Ag/AgBr-based nanomaterials synthesized viaa water/oil microemulsion and than that of the corresponding Ag/AgCl-based nanospecies synthesized by an oil/water microemulsion. An explanation has been proposed for these interesting findings. Our results suggest that thus-manufactured Ag/AgBr/GO plasmonic photocatalysts are promising alternatives to the traditional UV light or visible-light driven photocatalysts.

Herein, we have demonstrated that spherical and quasi-cubic Ag/AgCl-based plasmonic photocatalysts could be controllably synthesized by means of a one-pot surfactant-assisted method, wherein an oil-inwater system is employed as synthesis medium. We have found that thus-produced nanostructures can display stable photocatalytic performance for the photodegradation of Methyl Orange (MO) pollutant when energized with sunlight or visible light, where morphology dependent and enhanced photocatalytic activity could be realized. Compared with the Ag/AgCl nanospheres, their quasi-cubic counterparts exhibit much higher photocatalytic activity, which could be further enhanced upon hybridization with graphene oxide (GO). Moreover, in contrast to the spherical Ag/AgCl nanospecies formulated via a water-in-oil medium, those synthesized through the oil-in-water system display higher photocatalytic activity. On the basis of our experimental facts, a plausible explanation has been proposed for these significant findings. The investigation has not only one-pot controllably produced sunlight energized Ag/AgCl-based plasmonic photocatalysts with morphology dependent catalytic performance, but also essentially increased their catalytic activity.

Organic light-emitting transistors (OLETs) represent an emerging class of organic optoelectronic devices, wherein the electrical switching capability of organic field-effect transistors (OFETs) and the light-generation capability of organic light-emitting diodes (OLEDs) are inherently incorporated in a single device. In contrast to conventional OFETs and OLEDs, the planar device geometry and the versatile multifunctional nature of OLETs not only endow them with numerous technological opportunities in the frontier fields of highly integrated organic electronics, but also render them ideal scientific scaffolds to address the fundamental physical events of organic semiconductors and devices. This review article summarizes the recent advancements on OLETs in light of materials, device configurations, operation conditions, etc. Diverse state-of-the-art protocols, including bulk heterojunction, layered heterojunction and laterally arranged heterojunction structures, as well as asymmetric source-drain electrodes, and innovative dielectric layers, which have been developed for the construction of qualified OLETs and for shedding new and deep light on the working principles of OLETs, are highlighted by addressing representative paradigms. This review intends to provide readers with a deeper understanding of the design of future OLETs.

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Surfactant-assisted self-assembly (SAS) has received much attention for supramolecular nanoassemblies, due to its simplicity and easiness in realizing a controllable assembly. However, in most of the existing SAS protocols, the employed surfactants work only as a regulator for a controllable assembly but not as active species for function improvement. In this paper, we report that a porphyrin, zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), could be assembled to form one-dimensional (1D) supramolecular nanostructures via a SAS method, wherein graphene oxide (GO) plays a fascinating role of sheetlike surfactant. We show that, when a chloroform or tetrahydrofuran solution of ZnTPyP is injected into an aqueous dispersion of GO, 1D supramolecular nanoassemblies of ZnTPyP with well-defined internal structures could be easily formulated in a controllable manner. Our experimental facts disclose that the complexation of ZnTPyP with the two-dimensional GO nanosheets plays an important role in this new type of SAS. More interestingly, compared with the 1D ZnTPyP nanoassemblies formulated via a conventional SAS, wherein cetyltrimethylammonium bromide is used as surfactant, those constructed via our GO-assisted SAS display distinctly enhanced photocatalytic activity for the photodegradation of rhodamine B under visible-light irradiation. Our new findings suggest that GO could work not only as an emergent sheetlike surfactant for SAS in terms of supramolecular nanoassembly but also as functional components during the performance of the assembled nanostructures.