A novel route has been developed for surfactant-free synthesis of highly fluorescent gold quantum dots (GQDs) in N,N-dimethylformamide (DMF). The as-prepared GQDs show instinctive fluorescence and good solubility in water. The formation mechanism and functionalization of GQDs were investigated by UV-vis spectra, fluorescence excitation and emission spectra, mass spectra, and TEM observation. Ligand-dependent optical properties of functionalized GQDs were found to be dramatically different. The approach provides a facile method of functionalization of bare GQDs for further applications, such as fluorescent biolabels, energy transfer units, and light-emitting devices.

A visible near-infrared chemosensor (MCy-1) for mercury ions was successfully devised and characterized. A large red-shift (122 nm) of the absorption maximum of MCy-1 was observed. An important feature for the new chemosensor is its high selectivity towards mercury ions over the other competitive species, making the "naked-eye" detection of mercury ions possible.

An intramolecular charge-transfer (ICT) compound, (TCBD)2OPV3, has been synthesized and fabricated into one-dimensional nanotubes by a reprecipitation method. The observation of SEM and TEM showed the nanotubes were formed from their zero-dimensional precursors of hollow nanospheres. Reconstruction was found to happen during the morphology transition progress. The morphology transition and reconstruction are proposed to be a "curvature strain releasing" process driven by donor-acceptor dipole-dipole interactions. An aggregation-induced emission (AIE) effect was observed for (TCBD)2OPV3. Both aggregates of vesicles and nanotubes were observed to be good red emitters with near-infrared end emission of 750-850 nm, which endows the material with potential applications in the fields of optical devices, biosensors, and biolabels.

The synthesis and sensing characteristics of a new class of colorimetric and fluorometric dual-modal probe for mercury ion are outlined. Judicious placement of two dithia-dioxa-aza macrocycles on the BODIPY chromophore generates this interesting molecule. A highly Hg2+-selective fluorescence enhancing property (>7-fold) in conjunction with a visible colorimetric change from purple to red-pink can be observed, leading to potential fabrication of both "naked-eye" and ratiometric fluorescent detection of Hg2+.

In terms of microwave absorption, dielectric performance acts vital but has negative characteristics in attenuation and impedance matching. In this study, ZnO/nanoporous carbon (NPC)/reduced graphene oxide (RGO) materials have been fabricated through a simple and valid hydrothermal method derived from Zn metal–organic frameworks (MOFs). By changing the molar ratio of the precursors, the permittivity of the ZnO/NPC/RGO can be calculated, and the greatest balance between energy conservation and impedance matching eventually emerged with the addition of 4 mL of GO. It could be found that, at 14 GHz, a thin sample consisting of 40 wt % ZnO/NPC/RGO in the wax matrix exhibited minimum reflection loss of −50.5 dB with a thickness of 2.4 mm, and with a thickness of 2.6 mm, the effective microwave absorption bandwidth coverage is from 9.6 to 17 GHz. It is worth mentioning that we have also interpreted the relationships between the highest reflection loss values and matching thicknesses. This work not only proposes that ZnO/NPC/RGO samples are able to function as a perfect absorbent with broad frequency bandwidth and strong absorption but also provides better candidates in designing other lightweight microwave absorbents.

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Low-dimensional semiconductors have attracted a great deal of attention owing to their promising uses in constructing functional nanometer-scale electronic and optoelectronic devices. [1][2][3][4][5] Metal-organic charge-transfer (CT) complexes are of growing interest because of their unique solid-state physical properties. [6][7][8] In particular, with well-defined architecture,CT complexes are showing prominent merits over their bulk counterparts for applications in electrical and optical memory devices, sensors, and magnetic devices. [9][10][11] Many researchers therefore launched studies on the controllable synthesis of CT complexes. Tetracyanoquinodimethane (TCNQ)-based solidstate chemistry represents an area of considerable current interest in the field of materials science. [12][13][14] Although successful attempts to impart TCNQ-based CT complexes devices with high-quality performance, a sparsely investigate avenue for development is the exploration of materials based on other acceptors, [15][16][17] which may significantly enhanced the understanding of their intriguing physical and chemical, such as electronic, magnetic and optic, behavior. Tetracyanoanthraquinodimethane (TCNAQ; see Scheme S1 in the Supporting Information) shows more efficient electron-acceptor properties than TCNQ and has been extensively studied in conjugated polymers. [18,19] . However, studies on CT complexes based on TCNAQ are seldom reported.An active area of research has been the synthesis and fabrication of low-dimensional organic semiconductors for applications in field-emission cold cathodes. [20][21][22][23][24] Recently, we reported the field-emission properties of metal-organic chargetransfer complexes of Cu-TCNQ and Ag-TCNQ nanostructure arrays. Both the outstanding current density and the low turn-on field showed great potential for applications of organic charge-transfer complexes in field-emission flat displays.[23]These results encouraged us to fabricate new structures of metal-organic charge-transfer complexes for applications in further field emitters. Herein, we would like to report the facile fabrication of Cu-TCNAQ complexes on the nanometer scale. Controllable synthesis of large-area nanostructured Cu-TCNAQ films has been easily achieved. Field-emission measurements show that the Cu-TCNAQ complex is a potential candidate for field-emission cathodes. Figure 1 displays photographs of the large-area Cu-TCNAQ synthesized in acetonitrile (Fig. 1a) and acetone (Fig. 1b) solution. Figure 2a-b show the typical morphology as the reaction was performed in TCNAQ of acetonitrile solution. The nanowire film was grown on the copper foil after reaction for about 5 min in 1 mg mL -1 TCNAQ acetonitrile solution at room temperature. From Figure 2a, it can be seen that the nanowires with flexible shape are mostly lying down on the substrate. The high-magnification image (Fig. 2b) shows that the nanowires are entangled with each other. The nanowire is about 100 nm in diameter and several microme-

The optimized electromagnetic (EM) parameters are highly indispensable for outstanding microwave absorbers. Generally speaking, it is very necessary to suitably improve permittivity and permeability of the materials. The combination of magnetic/dielectric materials is a good choice. Herein, the irregular shaped FeNi/C composites were synthesized in N 2 atmosphere with unsatisfied EM parameters. To further optimize EM parameters and enhance microwave absorption abilities, constructing one-dimensional (1D) structure is also an excellent scheme. 1D FeNi/C nanofibers were successfully obtained by electrospinning technology combined with heat treatment. Enhanced microwave absorption abilities can be fulfilled by conductive network structure, better dielectric loss, and stronger interface polarization intensity. Moreover, carbonized time toward nanofibers plays a key role in microwave absorption, which could influence complex permittivity and dielectric loss of materials. It is found that FeNi/C nanofibers with highly carbonized degree display better microwave absorbing properties. The reflection loss (RL) values less than −10 dB can be observed in 12.8−17.2 GHz (a broad bandwidth of 4.4 GHz) with an absorber thickness of only 1.8 mm. The absorber with a thickness of 2.7 mm has the minimum RL value of −24.8 dB at 9.4 GHz. In this regard, these nanofibers are very likely to be used as EM-wave absorbers in practical application. Furthermore, this work provides a useful strategy to optimize electromagnetic parameters and absorption abilities of metal/carbon absorbers. It may promote the development of 1D metal/carbon composites in microwave absorption field.