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The change of refractive index resulting from the isomerization of photochromic molecules under light irradiation reconfigures lattice plasmon resonances, which allows for the realization of dynamically and continuously tunable plasmonic lasers.

We demonstrate high-performance photodetectors based on Eu-doped 2D perovskite nanowire arrays. The pure crystallographic orientation enables efficient carrier transport and the doped Eu ions effectively suppress the trap density in the nanowire arrays. As a result, the optimized Eu-doped photodetectors show an excellent responsivity of 6.24 A W

The hybridization of local and charge transfer excited states is proven to accumulate bright excitons for both optically pumped lasing and electroluminescence at high current density.

We demonstrate a controllable photoluminescence anisotropy amplification in organic luminescent radical-doped microcrystals via exciton funneling. The widely tunable doping ratio resulting from very similar molecular structures between hosts and guests leads to a freely tailorable exciton funneling process, which paves an avenue for the construction of high-performance polarizing optical elements.

Switchable multimode microlasers are of great significance to the development of photonic devices with high integration levels. Herein, we demonstrate an acid/alkaline gas-responsive multimode AIEgen@starch microsphere-based microlaser. The aggregation-induced emission (AIE) active fluorescent dye ASCPI was used as the gain medium in this study. ASCPI was weakly emissive in water but became highly emissive when introduced to a starch microsphere as a guest molecule. The resultant ASCPI@starch microsphere worked well as a typical whispering-gallery-mode microlaser. The laser mode wavelengths were size-dependent. Due to the sensitivity of ASCPI to pH, the output of the microlaser could be switched to a shorter wavelength by acetic acid vapor treatment or a longer wavelength by NH3 vapor treatment. This work will provide useful enlightenment for the rational design of effective switchable lasers using AIE materials with simple preparation procedures.

The invention and development of the laser have revolutionized science, technology, and industry. Metal halide perovskites are an emerging class of semiconductors holding promising potential in further advancing the laser technology. In this Review, we provide a comprehensive overview of metal halide perovskite lasers from the viewpoint of materials chemistry and engineering. After an introduction to the materials chemistry and physics of metal halide perovskites, we present diverse optical cavities for perovskite lasers. We then comprehensively discuss various perovskite lasers with particular functionalities, including tunable lasers, multicolor lasers, continuous-wave lasers, single-mode lasers, subwavelength lasers, random lasers, polariton lasers, and laser arrays. Following this a description of the strategies for improving the stability and reducing the toxicity of metal halide perovskite lasers is provided. Finally, future research directions and challenges toward practical technology applications of perovskite lasers are provided to give an outlook on this emerging field.

Photonic barcodes have attracted extensive attention due to their promising applications in multiplexed high throughput bioassays, item tracking, information security, etc. Organic luminescent materials, capable of assembling into various micro/nanostructures as a result of their outstanding processability, afford a fundamental model for designing novel micro/nanoscale photonic barcodes. In this highlight, we review recent advances in micro/nanoscale photonic barcodes based on organic materials. This highlight starts by introducing the significance of tiny photonic barcodes and discussing why organics have become dominant. Then we present the research progress on organic photonic barcodes in terms of a series of strategies including graphical encoding, spectroscopic encoding and a combination of them both. In the following part, we focus on the construction of covert photonic barcodes based on near-infrared luminescence and responsive excited state processes, which have shown great potential in advanced anti-counterfeiting. Finally, we present our views on the current challenges and the future development of organic micro/nanoscale photonic barcodes. We believe that a comprehensive understanding on this topic would significantly contribute to the advancement of organic photonic barcodes for a broad range of applications.

Organic polymorphs with tunable luminescence are crucial in developing organic luminescent materials, but the regulation of molecular packing modes and intermolecular interactions in organic crystals remains a challenge. Here, we report three triphenylamine–benzothiazole (TZ) compounds by systematically changing the substituents, resulting in different crystal emission characteristics. The polymorphs of blue emission (TZ-1B) and cyan emission (TZ-1C) crystals are obtained by controlling the crystallization conditions, however, we could not obtain organic polymorphs of TZ-2 or TZ-3 in various solvent systems. By molecular systems and detailed single crystal analysis, it is found that appropriate substituents play a key role in manipulating the intermolecular interactions and the molecular packing modes to affect the optical properties of organic crystals. Moreover, TZ-1C exhibits blue-shifted mechanochromism, while TZ-1B does not. More importantly, TZ-1B exhibits a lasing emission at 454 nm with a low threshold and a high cavity quality factor. TZ-1C exhibits amplified spontaneous emission (ASE) at 462 nm. Thus, the molecular systems provide a reasonably potent molecular strategy to understand the molecular packing structure–fluorescence property relationship.

The controlled construction of organic heterostructured architectures derived from molecules with similar nucleation thresholds and concentrations has been rare and remains a great challenge. Herein, we report a sequential epitaxial growth to synthesize dual-color-emitting organic heterostructures with 9,10-bis(phenylethynyl)anthracene (BPEA) microwire trunks and tris-(8-hydroxyquinoline)aluminium (Alq3) microstructure branches by an anti-solvent induced sequential crystallization strategy. During the epitaxial growth process, the hydrogen-bonding interactions of the anti-solvent and solvent cause a large change in the solubility and crystallization rate of BPEA and Alq3 molecules in the mixed system, which facilitates sequential crystallization of organic molecule pairs with similar nucleation thresholds and concentrations into desired heterostructures by manipulating the synergism of anti-solvents and solvents. The Förster resonant energy transfer process in heterostructures could be modulated by varying the structure of heterostructures, such as the shape, amount and angles of the branches. The present synthesis strategy provides a unique insight into the detailed formation mechanism of complex organic heterostructures, further guiding the construction of more functional heterostructure materials.

Low-dimensional organic materials have given rise to tremendous interest in optoelectronic applications, owing to their controllable photonic properties. However, the controlled-synthesis approaches for organic nano-/micro-architectures are very difficult to attain, because the weak interaction (van der Waals force) between the organic molecules cannot dominate the kinetic process of crystal growth. We report a simple method, which involves selective adhesion to the organic crystal plane by hydrogen-bonding interaction for modulating the crystal growth process, which leads either to the self-assembly of one organic molecule into two-dimensional (2D) microsheets with an obvious asymmetric light propagation or one-dimensional (1D) microrods with low propagation loss. The method of tailoring the structures and photonic properties for fabricating different micro-structures would provide enlightenment for the development of tailor-made mini-sized devices for photonic integrated circuits.

Directing the architecture of complex organic nanostructures is desirable and still remains a challenge in areas of materials science due to their structure-dependent collective optoelectronic properties. Herein, we demonstrate a simple and versatile solution strategy that allows surface tension to drive low-dimensional nanostructures to aggregate into complex structures via a lab in a droplet technique. By selecting a suitable combination of a solvent and an anti-solvent with controllable surface tension difference, the droplets can be automatically cracked into micro-droplets, which provides an aggregation force directed toward the centre of the droplet to drive the low-dimensional building blocks to form the special aggregations during the self-assembly process. This synthetic strategy has been shown to be universal for organic materials, which is beneficial for further optimizing the optoelectronic properties. These results contribute to gaining an insightful understanding on the detailed growth mechanism of complex organic nanostructures and greatly promoting the development of organic nanophotonics.

Ultracompact coherent light sources with broadband wavelength tunability and subwavelength optical waveguiding have attracted extensive attention due to their potential applications ranging from multicolor detection to multiband on-chip photonic communication. Metal–dielectric nonlinear structures, which comprise nonlinear dielectric materials and metal films, have been widely used to generate nanoscale broadband tunable coherent light sources through the second-harmonic generation process below the diffraction limit. However, restricted by high ohmic losses at the metal–dielectric surface, subwavelength propagation of SHG signals with low loss remains a big challenge. Here, a novel strategy is utilized to reduce the propagation loss of SHG signals based on the coupling between the waveguide mode and plasmonic mode in a hybrid plasmonic waveguide (HPW). The generated hybrid plasmonic mode in the HPW exhibits strong optical confinement around the nonlinear dielectric and insulating gap, which is beneficial for minimizing the ohmic losses at the metal–dielectric interface and enhancing the light–matter interaction below the diffraction limit. Moreover, under the phase matching condition, the propagation loss of SHG signals is partially compensated for by the frequency conversion of the fundamental wave (FW) through the SHG process. As a result, low propagation loss of enhanced SHG signals at a subwavelength scale is realized in HPWs.

Solid-state fluorescent materials have attracted a surge of interest in recent years due to their wide applications in the fields of photoelectric devices, memory storage and fluorescent probes. Compared to the synthesis of new molecules, exploring new properties in known molecules is a facile approach to obtain functionalized fluorescent materials. In this report, we systematically explored the solid-state photoluminescence properties and applications of 7-(diethylamino)coumarin-3-aldehyde (DCA) and 7-(diethylamino)coumarin-3-carboxylic acid (DCCA). Both fluorophores exhibited a special concentration-dependent emission effect. They displayed polymorphism dependent solid-state emission and single crystal analysis revealed that enhanced overlap between neighbouring molecules resulted in a red-shifted emission. Crystal-to-crystal transformation has also been achieved for both DCA and DCCA by employing an external thermal treatment. In addition, the solid powder of DCA and DCCA displayed fluorescence response to HCl and NH3 gas with high sensitivity. Furthermore, 1D micromaterials were assembled for both fluorophores and DCA exhibited outstanding optical waveguide behavior.

Organic microlasers are miniaturized coherent light sources with great promise for advancing the field of optoelectronics. Recently, host–guest composite organic microlasers, where the host materials provide spatial confinement for the organic gain materials, have captured much research interest because the host–guest composite material systems endow the organic microlasers with improved lasing performances, such as low threshold, high stability, and excellent tunability. In this Review, we explore the latest advancements in the development of host–guest composite organic microlasers, and offer our perspective on future improvements and trends. Special emphasis is put on the construction strategies and the unique laser properties of the organic microlasers based on host–guest confinement systems. The comprehensive understanding of the relationship between laser performances and the synergistic interactions of the host and guest materials would provide a useful guidance for the design and fabrication of novel organic microlasers.

We demonstrate the fabrication of organic high Q active whispering-gallery-mode (WGM) resonators from π-conjugated polymer by a controlled emulsion-solvent-evaporation method, which can simultaneously provide optical gain and act as an effective resonant cavity. By measuring the shift of their lasing modes on exposure to organic vapor, we successfully monitored the slight concentration variation in the chemical gas. These microlaser sensors demonstrated high detection sensitivity and good signal repeatability under continuous chemical gas treatments. The results offer an effective strategy to design miniaturized optical sensors.

Refractive index is one of the important physical properties, which is widely used in separation and purification. In this study, the refractive index data of ILs were collected to establish a comprehensive database, which included about 2138 pieces of data from 1996 to 2014. The Group Contribution-Artificial Neural Network (GC-ANN) model and Group Contribution (GC) method were employed to predict the refractive index of ILs at different temperatures from 283.15 K to 368.15 K. Average absolute relative deviations (AARD) of the GC-ANN model and the GC method were 0.179% and 0.628%, respectively. The results showed that a GC-ANN model provided an effective way to estimate the refractive index of ILs, whereas the GC method was simple and extensive. In summary, both of the models were accurate and efficient approaches for estimating refractive indices of ILs.

Nanophotonics have recently captured broad attention because of their great potential in information processing and communication, which may allow rates and bandwidth beyond what is feasible in the realm of electronics. Organic materials could be well suitable for such applications due to their ability to generate, transmit, modulate and detect light in their lightweight and flexible nanoarchitectures. Their distinct nanophotonic properties strongly depend on their extrinsic morphologies and intrinsic molecular excited-state processes. In this feature article, we mainly focus on a comprehensive understanding of the relationship between molecular excited-state processes and the advanced photonic functionalities of organic micro/nano-crystals in recent organic nanophotonic research, and then expect to provide enlightenment for the design and development of tiny photonic devices with broadband tunable properties by tailoring the excited-state processes of organic microcrystals.

Predicting hydrogen sulfide (H2S) solubility in ionic liquids (ILs) is vital for industrial gas desulphurization. In this work, the qualitative analysis of the influence of cations and anions on the H2S solubility in ILs has been conducted. The results indicate that anions play an important role in determining the H2S solubility in ILs. Subsequently, two novel quantitative structure–property relationship (QSPR) models are developed based on charge distribution area (Sσ-profile) descriptors and an extreme learning machine (ELM) algorithm. To develop the QSPR models, a total of 1282 pieces of data belonging to 27 ILs are employed to validate the models. The average absolute relative deviation (AARD%) and coefficient of determination (R2) of the two QSPR models of the entire data set are 3.73% and 0.998, as well as 3.80% and 0.997, respectively. These results suggest that the proposed QSPR models can be useful for the prediction of H2S solubility in ILs.

A beneficial "microenvironment effect" on the efficiency of confined electrocatalysts is predicted by theory. However, examples of its experimental confirmation are scarce for catalysts based on polyoxometalates for the hydrogen evolution reaction (HER). For this purpose, the cyclic 48-tungsto-8-phosphate [H7P8W48O184](33) (P8W48) was fixed in a 3D configuration on reduced graphene oxide sheets (rGO) to boost its HER activity. The HRTEM imaging and the solid state P-31 NMR spectrum of P8W48/rGO reveal a strong interaction between individual P8W48 and transparent rGO sheets. The calculation of the interaction between P8W48 and graphene (G) sheets is difficult to perform within a reasonable period of time because of the large size and very high overall negative charge of P8W48. However, as P8W48 is symmetrical, a quarter of its structure [H2P2W12O48](12-) (P2W12) was extracted as a DFT calculation model. As P8W48 in P8W48/rGO is neutral, due to surrounding counter cations, the calculation model P2W12 is neutral with protons considering the affordable computational time. The adsorption energy for P2W12 on G (-1.55 eV) and the charge transfer between P2W12 and G (0.66 vertical bar e vertical bar) indicate that a strong interaction between P2W12 and G sheets exists. Kinetic studies show that the P8W48/rGO hybrids display excellent HER activity in acid, further confirmed by reproducible generation of hydrogen with quantitative faradaic yield and a high turnover frequency (11 s(-1) at 295 mV overpotential) for a noble metal-free electrocatalyst. Importantly, the overpotentials required for the HER compare well with those of the commercial Pt/C (20 wt% Pt), which indicates that P8W48/rGO is a promising cheap HER electrocatalyst. We demonstrate here the most convincing experimental evidence of the "microenvironment effect" on HER electrocatalysis by a polyoxometalate.

Two isostructural dense lanthanide metal–organic frameworks derived from an extended ligand 1,3,5-tris(4-carboxyphenyl)benzene (H3BTB), [Ln(BTB)H2O]n (Ln = Eu, 1; Ln = Dy, 2), which are constructed via a cross-like folding assembly strategy, were yielded by ‘two-step warming solvothermal synthesis’. Complex 1 shows luminescence while complex 2 exhibits field-induced two-step magnetic relaxation.

In this work, we employ the Corey–Fuchs reaction followed by coupling reactions to develop a series of π-conjugated aggregation-induced emission (AIE) small-molecule luminophores (DT2A, DT3A and DT4A) through a 2,2-(2,2-diphenylethene-1,1-diyl)dithiophene (DPDT) core with different amounts and different strengths of TPA peripheral moieties. Interestingly, these molecules give obviously higher solid fluorescent quantum efficiency and AIE phenomena. In particular, the thin film of DT3A exhibited the highest fluorescent quantum efficiency of ca. 25% and the DT2A showed the highest αAIE of 78. Moreover, the excellent optical waveguide applications of DT2A and DT4A were achieved because of their excellent self-assembly properties. Meanwhile, piezofluorochromic behavior with a large red shift of 35 nm only appeared when DT4A was ground using a pestle, because DT4A inserted more TPA and changed the twisting conformation. The piezofluorochromic behavior can be recovered to its original color by fuming with solvent. Finally, DT2A and DT4A were utilized as fluorescent probes to detect nitroaromatic/nitroaliphatic compounds and showed evident fluorescence quenching. These results indicate a huge potential to develop bright AIEgens based on DPDT core units and also provide insights into understanding how piezofluorochromism, optical waveguides and explosive detection properties are influenced by alternating the spatial symmetry of AIE materials with different numbers of TPA terminal groups.

A series of dialkoxybenzo[j]fluoranthene derivatives were readily and efficiently synthesized in gram scale starting from the commercial 6- or 7-methoxy-1-tetralone. The crystal structures of the BjF derivatives were described, and their structure–optical properties in solution and in the solid state were investigated. Moreover, this kind of organic material also exhibited excellent optical waveguide behavior owing to their large Stokes shifts and high crystallinity.

A series of tetrahydro[5]helicene-based dye molecules were efficiently synthesized and the helical structural features of their tetrahydro[5]helicene skeletons were confirmed by the crystal structures. The substituent effect of the dyes on their photophysical properties was then investigated. Consequently, it was found that compared with hydroxymethyl and ester groups, the introduction of imide to the tetrahydro[5]helicene skeleton could result in not only red shifts of their absorption and emission bands, but also higher quantum yields and larger Stokes shift. Especially, intense full-color fluorescence emissions in both solution and solid states could be achieved just by changing the substituents with different electron-donating abilities in the tetrahydro[5]helicene imide skeleton. Moreover, a significant solvent-effect on the emissions of the tetrahydro[5]helicene-based organic dyes was also found. The density functional theory calculations further demonstrated that with the increase of the electron-donating ability of the substituents, the energy gaps of the tetrahydro[5]helicene-based dyes gradually decreased, which theoretically elucidated the substituent effect of the dyes on their photophysical properties. Additionally, an optical waveguide application of the tetrahydro[5]helicene-based imide dye is shown as well.

One-dimensional (1D) organic nanostructures and their hierarchical assemblies have sparked great interest in sensing applications recently owing to convenient detection, high sensitivity and selectivity, and real-time monitoring with fast response time afforded by systems that utilize them. In this mini-review, we focus on the construction and modulation of 1D nanostructures from single- or multicomponent organic compounds, and the relevant approaches that have employed them into sensing applications. Furthermore, major obstacles and future steps towards ultimate organic nanosensors based on 1D structures are discussed.

A host–guest inclusion complexation self-assembly strategy was developed for the synthesis of SHG-active low dimensional supramolecular crystals (LDSCs). p-Nitroaniline guest molecules with high inherent second-order polarizability were introduced into the cavities of the β-cyclodextrin host to form supramolecular inclusion complexes, which were then assembled into microscale crystalline structures with an anti-solvent diffusion combined solvent-evaporation-induced self-assembly method. Two distinct types of LDSCs with controllable dimensions were obtained by altering the polarity of anti-solvents and the concentration of supramolecular monomers. Each type of LDSCs exhibited its characteristic SHG response to the polarized incident signals, which is attributed to the inherent crystal structures.

Due to their potential performances in photonic integrations, one-dimensional single-crystalline nanostructures constructed from organic luminescent molecules have generated wide research interests during the past few years. Here, we highlight the two main kinds of applications in the future of miniaturized photonic circuits: optical waveguides and optically pumped lasers. This article concludes with a summary and our personal view about the direction of future development in organic opto-functional waveguides and lasers as photonic devices.

Exciton–polaritons arising from strong coupling between excitons and photons are composite bosons which are half light and half matter. Due to their relatively light effective mass (seven orders of magnitude less than the mass of a hydrogen atom), they could potentially condense at temperatures much higher than those required for atom Bose–Einstein condensations (tens of nanokelvins). This makes them not only a perfect model for fundamental studies of dynamical Bose–Einstein condensates, but also a suitable system for the design of novel optical components. Various polaritonic devices such as polariton parametric amplifiers, optically pumped polariton lasers and polariton light-emitting diodes have been achieved. With the recently reported electrically pumped polariton lasers added to the list, the polaritons seem to have made their way out of the laboratory and have a bright, white future ahead.

The electrogenerated upconversion was achieved in the uniformly doped organic nanowires based on triplet energy transfer from tris(2,2'-bipyridyl)ruthenium(II) to 9,10-diphenylanthracene.

A red-emissive barbituric acid-functionalized tetraphenylethene derivative (TPE-HPh-Bar) was designed and synthesized. TPE-HPh-Bar exhibits the effect of twisted intramolecular charge transfer due to the interaction of its donor and acceptor units. Whereas TPE-HPh-Bar emits faintly in solution, it becomes a strong emitter in the aggregated state, demonstrating a phenomenon of aggregation-induced emission. TPE-HPh-Bar can self-assemble into nanospheres upon natural evaporation of its solutions. In the presence of melamine, nanorods and (un)sealed nanotubes are formed, the content of which depends on the melamine amount. The crystalline nanorods of TPE-HPh-Bar grown from diethyl ether/hexane solution exhibit a good optical waveguiding effect with a low optical loss (0.137 dB μm−1). Such attributes make the material to find wide applications in many areas such as biological imaging and optoelectronic nano-devices.

In this work, a heteroatom-containing luminogen (TPE-Py) with multi-functionalities was synthesized in a reasonable yield by melding a pyridinium unit with tetraphenylethene through vinyl functionality. TPE-Py is weakly emissive in solution but becomes a strong emitter when aggregated as nanoparticle suspensions in poor solvents or in the solid state, displaying a phenomenon of aggregation-induced emission. Crystallization generally weakens and red-shifts the light emission. The crystalline aggregates of TPE-Py, however, emit stronger and bluer light than their amorphous counterparts. The solid-state emission of TPE-Py can be reversibly switched between green and yellow color by grinding–fuming and grinding–heating processes with a high contrast due to the transformation from the crystalline to the amorphous state and vice versa. The large Stokes shift and well-ordered molecular arrangement of the crystalline microrods of TPE-Py make it promising as an optical waveguide material with a low optical loss coefficient of ∼0.032 dB μm−1. TPE-Py works as a good fluorescent visualizer for specific staining of mitochondria in living cells with a high photostability, thanks to its hydrophobic and cationic features.

We have demonstrated a new fabrication methodology for gold nano- and microtubes with regular cylinders by vapor-induced strain of porous thin films, which exhibit highly sensitive SERS signals for Rhodamine 6G detection. The strain originates from the temperature difference in the top and bottom of the gold film, which is brought about by the vapor of the Se powder, because Selenium has a low melting point. Around its melting point, Se appears in the vapor state, while the gold nanofilms remain in the solid phase. By exploiting such vapor-driven self-rolling of the gold film, shrinkage or collapse of the tube wall by capillary forces can be effectively avoided. Moreover, the diameter and the length of the obtained gold tubes can be well controlled by changing the Se powder evaporation temperature and the thickness of the gold film. The wall number of the tubes varied with the evaporation time and speed of the Se powder. Attributed to the larger surface area of the porous structures, the tubes exhibit SERS signals nearly 20 times larger than those of the gold film. This means that the detection limit of gold film is enhanced by over one order of magnitude.

A microporous bithiophene polymer (MBP) stable up to 460 °C was synthesized using bithiophene and biphenyl as building blocks through Suzuki cross-coupling. The as-obtained MBP product exhibits green fluorescence peaked at 530 nm, and most interestingly, a two-photon fluorescence was observable from MBP upon excitation by an 800 nm femtosecond laser.

Optical waveguides synthesized at the micro/nanoscale have drawn great interest for their potential applications in high speed miniaturized photonic integrations. In this Perspective article, we mainly focus on the related works on active optical waveguides based on functional small organic molecules in micro/nano regime. We begin with a general overview of recent progress in sub-wavelength optical waveguides, including the development of waveguide materials of inorganic semiconductors, polymers, and small organic molecules. Then brief highlights are put on the recently reported organic optical waveguides with various unique optical properties induced by the ordered molecular aggregations in the micro/nano-sized solid-state structures, such as polarized emission, lasing, aggregation-induced enhanced emission, etc. This article concludes with a summary and our personal view about the direction of future development in organic opto-functional waveguides as photonic devices.

Single-crystal ZnS1−xSexnanoribbons with various compositions were synthesized through an Au-catalyzed vapor transport method. Under two-photon pumping with an 800 nm femtosecond pulsed laser, the spontaneous emission peak of the ternary nanoribbons undergoes a gradual red-shift from 422 to 464 nm with the increase of Se content. When the pump energy densities are increased above the thresholds, the nanoribbons exhibit a tunable upconverted laser emission accompanied by a dramatic decrease in spectral linewidth as a set of sharp peaks on the corresponding wavelengths of each sample, featuring the occurrence of stimulated emission. Two components appear in the fluorescence lifetimes, which indicate that the ZnS1−xSexnanoribbons have two different recombination centers. Both lifetime components decrease with the increase of pump energy, further confirming the occurrence of stimulated emission. The two-photon pumped lasing behavior was also observed from single nanoribbons, in which the photoluminescence (PL) spectra are composed of multimode of lasing. The distinct modes show gain competition and pronounced shifts as a function of excitation density.

Composite nanomaterials fabricated from organic luminescent molecules have generated wide research interests during the past few years. These optically active binary nanostructures are of great importance not only for fundamental investigations on energy transfers, but also for various practical applications in light emitting, optical waveguiding, fluorescence switching and chemical sensing. Therefore, many kinds of organic composite nanostructures have been synthesized by different techniques, including liquid-phase mixing, vapor-phase doping, chemical reaction and surface modification. In this Focus, we describe the recent progress in our group toward the construction of organic composite nanomaterials and studies on their tunable luminescent behaviors via energy transfers.

The effects of molecular structures on nanostructural morphologies have been studied through the preparation of nanospheres, square nanowires, and nanocubes from three isomeric molecules of bis(iminopyrrole)benzene.

Nanocrystals with tunable morphologies and optical properties were successfully fabricated from an organic functional low-molecular-weight compound, 2,4,5-triphenylimidazole (lophine), through a sonication technique.