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This work reports the synthesis and application of highly tuned cadmium-free green and red InPZnSe1−xSx/ZnS quantum dots (QDs) in QD enhanced liquid crystal displays (LCD). The emissions of the quantum dots were synthetically tuned to sharp emissions at low full-width at half maximum. The QDs were incorporated in LCD devices as quantum dot enhancement film (QDEF) or as a quantum dot incorporated color filter (QDCF). Synthetic tuning of the gradient inter-shell in the QDs leads to reduced full width at half-maximum, resulting in sharp green and red emissions from both types of devices. The application of the same QDs to devices using these different integration techniques shows the superiority of QDCF devices over QDEF ones. The RGB color gamut of a QDCF-LCD was 81.4% of REC.2020 in the CIE 1931 color space compared to 71.2% obtained for a QDEF-LCD display. The improved performance of QDCF was mainly due to the optimal interactions between the green QDs and the green color filter. The superior performance of cadmium-free InPZnSe1−xSx/ZnS QDCFs in LCDs make them well-suited for ultra-high-definition TV formats.

Charge-transfer (CT) states play a critical role in harvesting nonemissive triplets realized by triplet-to-singlet conversion through spin mixing to generate thermally activated delayed fluorescenc...

Perovskite CsPbX3 (X = Br, Cl, and I) nanostructures have been intensively studied as they are luminescent, photovoltaic, and photosensitizing active materials. Two-dimensional (2D) transition-meta...

Composite metal oxide-coated tungsten cathodes were formulated as efficient and reliable thermo-electron sources for vacuum ultraviolet ionizers. Cathode suspensions were prepared by adding...

In this topical review of two-photon stereolithography (TPS), we discuss novel materials and demonstrate applications of this technology. Two-photon-initiated chemical processes are used to fabricate arbitrary three-dimensional structures in TPS. In the first part of this article, the development of novel photoactive materials to fabricate pure inorganic or organic-inorganic hybrid microstructures is discussed. The second part discusses the fabrication of functional microstructures for highly specific applications to demonstrate the importance of TPS in different fields of science.

Functionalized perovskite CsPbBr3 quantum dots (CsPbBr3-QDs) were loaded on the surface of a p-type organic rubrene (5,6,11,12-tetraphenyltetracene) nanosheet (NS) for the fabrication of a new hybrid nano-system. Using a high–resolution laser confocal microscope, the nanoscale photoluminescence (PL) characteristics of the CsPbBr3-QDs/rubrene-NS hybrids were investigated. We observed a significant enhancement of the PL intensity of the rubrene-NS after the hybridization with the CsPbBr3-QDs, which originated from the fluorescence resonance energy transfer from the CsPbBr3-QDs to the rubrene-NS. The PL enhancement ratio varied according to the density of the QDs on the NS. To investigate the hybridization effect with CsPbBr3-QDs on the electrical characteristics of the rubrene-NS, we fabricated field-effect transistors (FETs) using the pristine and hybrid samples as an active layer. The currents of both FETs using the pristine rubrene-NS and hybrid QDs/rubrene-NS increased with light irradiation through the contribution of photo-excited charges. After the hybridization with the CsPbBr3-QDs on the rubrene channel, both the electrical current and mobility decreased compared with the pristine rubrene-based FET. This can be explained by the relative decrease of hole concentration in the active channel region near dielectric layer through the interfacial charge transfer between the QDs and the NS, as well as the de-doping effect of the QDs on the rubrene-NS. Thus, we observed the energy and charge transfer effects for the CsPbBr3-QDs/rubrene-NS hybrids, which can be applied to advanced nanoscale photonics and optoelectronics.

When periodically packing the intramolecular donor-acceptor structures to form ferroelectric-like lattice identified by second harmonic generation, our CD49 molecular crystal shows long-wavelength persistent photoluminescence peaked at 542 nm with the lifetime of 0.43 s, in addition to the short-wavelength prompt photoluminescence peaked at 363 nm with the lifetime of 0.45 ns. Interestingly, the long-wavelength persistent photoluminescence demonstrates magnetic field effects, showing as crystalline intermolecular charge-transfer excitons with singlet spin characteristics formed within ferroelectric-like lattice based on internal minority/majority carrier-balancing mechanism activated by isomer doping effects towards increasing electron-hole pairing probability. Our photoinduced Raman spectroscopy reveals the unusual slow relaxation of photoexcited lattice vibrations, indicating slow phonon effects occurring in ferroelectric-like lattice. Here, we show that crystalline intermolecular charge-transfer excitons are interacted with ferroelectric-like lattice, leading to exciton-lattice coupling within periodically packed intramolecular donor-acceptor structures to evolve ultralong-lived crystalline light-emitting states through slow phonon effects in ferroelectric light-emitting organic crystal., Understanding the underlying spin- and photo-physics of ultralong-lived light emission in organic materials remains a significant challenge. Here, the authors report spin-orbital coupling and slow phonon effects in light-emitting organic molecules and elucidate their underlying physics.

Perovskite CsPbX

Recent advancements in nanotechnology have continued to stimulate the development of functional devices based on nanomaterials. However, the controllable assembly of these tiny nanomaterials into functional structures is still a big challenge for further applications; nowhere is this more obvious than in the field of nanodevices. Currently, despite the fact that self-assembly technologies have revealed great potential to reach this end, serious problems with respect to morphology control, designable assembly and even flexible patterning set huge obstacles to the fabrication of functional devices. Nowadays, in addition to self-assembly technologies that make use of interaction forces between different objects, photodynamic assembly (PDA) technology has emerged as a promising route to architect functional materials with the help of optical driving forces towards device fabrication. In this review, we summarize the recent developments in PDA technology for the designable patterning of nanoparticles (NPs). The basic fundamentals of PDA that resort to optical trapping (OT) and typical examples regarding far-field/near-field OT for the PDA of various NPs have been reviewed. In particular, femtosecond laser induced photodynamic assembly (FsL-PDA), which enables the designable patterning of NPs through a direct writing manner, has been introduced. Finally, the current challenges and future prospects of this dynamic field are discussed based on our own opinions.

Inorganic perovskite CsPbBr3 quantum dots (QDs) are potential nanoscale photosensitizers; moreover, two-dimensional (2-D) molybdenum disulfide (MoS2) has been intensively studied for application in the active layers of optoelectronic devices. In this study, heterostructures of 2D-monolayered MoS2 with zero-dimensional functionalized CsPbBr3 QDs were prepared, and their nanoscale optical characteristics were investigated. The effect of n-type doping on the MoS2 monolayer after hybridization with perovskite CsPbBr3 QDs was observed using laser confocal microscope photoluminescence (PL) and Raman spectra. Field-effect transistors (FETs) using MoS2 and the MoS2–CsPbBr3 QDs hybrid were also fabricated, and their electrical and photoresponsive characteristics were investigated in terms of the charge transfer effect. For the MoS2–CsPbBr3 QDs-based FETs, the field effect mobility and photoresponsivity upon light irradiation were enhanced by ~ 4 times and a dramatic ~ 17 times, respectively, compared to the FET prepared without the perovskite QDs and without light irradiation. It is noteworthy that the photoresponsivity of the MoS2–CsPbBr3 QDs-based FETs significantly increased with increasing light power, which is completely contrary to the behavior observed in previous studies of MoS2-based FETs. The increased mobility and significant enhancement of the photoresponsivity can be attributed to the n-type doping effect and efficient energy transfer from CsPbBr3 QDs to MoS2. The results indicate that the optoelectronic characteristics of MoS2-based FETs can be significantly improved through hybridization with photosensitive perovskite CsPbBr3 QDs.

Novel donor-donor type alternating copolymers (8CDT-TT and 16CDT-TT) derived from cyclopentadithiophene (CDT) and thienothiophene (TT) moieties that differ from solubilizing side chains were successfully synthesized and characterized. After the synthesis of CDT-TT-based conjugated polymers with dioctyl and dihexadecyl side chains, their optical, thermal, structural and semiconducting properties were investigated. Organic thin-film transistors fabricated from 8CDT-TT and 16CDT-TT exhibit carrier mobilities as high as 3.92×10-4 and 1.05×10-3 cm2V-1s-1, respectively. Bulk heterojunction solar cells fabricated using a polymer:PCBM blend ratio of 1:3 exhibit power conversion efficiencies of 2.12 and 1.84% for 8CDT-TT and 16CDT-TT, respectively.

This paper reports photoexcitation-enhanced magnetization in γFe2O3–graphene (zero dimensional–two dimensional) van der Waals heterostructure based on the experimental studies of steady-state pump–probe measurements in magnetic field. It is observed that applying a magnetic field on the γ-Fe2O3/graphene material suspended in an organic solvent can cause a light scattering on the probe beam in the absence of pump beam, leading to a magnetic field effect of light scattering. This result shows that the magnetization on the γ-Fe2O3 nanoparticles can lead to a partial orientation of Fe2O3–graphene heterostructure components suspended in liquid. This effect of magnetic field on light scattering is caused by the dynamic magnetization of the superparamagnetic–semiconducting hybrid material. Interestingly, applying the pump beam functioning as photoexcitation can lead to an enhancement on the scattering of probe beam, increasing magnetic field effect of light scattering. The increased magnetic field effect of ligh...

Nano-stereolithography, also known as two-photon direct writing is widely used for fabrication of the three-dimensional microstructure with submicron resolution. Heirarchical three-dimensional meshed microstructures are crucial for microelectromechanical systems (MEMS), photonics and biotechnological applications. Routine study for various applications using such structures requires fabrication of many sets of structures. Conventionally such meshed microstructures are constructed through layer-by-layer accumulation with discrete point-to-point laser scanning. This technique is time consuming, leading to long fabrication times placing constraints on practical applications as well as optimization of structures. In this work we propose continuous longitudinal laser scanning method as an effective means for direct writing of hierarchical three-dimensional meshed microstructures. The advantages of continuously longitudinal laser scanning method are explored for its time economy and fabrication effectiveness; a fabrication window is suggested to determine the fabrication parameter easily according to laser power and structural design.

Conjugated polymers have attracted considerable attention due to their versatile applications in the fields of organic optoelectronic devices. In this study, we describe the synthesis and p...

This study demonstrates the influence of the orbit-orbit interaction on the photoluminescence quantum efficiency (PLQE) of metal halide perovskite quantum dots (QDs) through the Rashba effect. The orbit-orbit interaction between excitons was characterized by using the minimal excitation intensity required to generate a photoluminescence difference (ΔPL) between linearly and circularly polarized photoexcitations. It was observed that changing the surface functionalization from PFOA-OA to PFSH-OAm and OA can largely increase the minimal excitation intensity for generating ΔPL. This indicates that the orbit-orbit interaction is essentially decreased in CsPbBr

In this presentation we discuss our attempts at balancing the desirable, and often mutually exclusive properties of resolution and mechanical stability with radical polymerizable photoresists in two-photon lithography (TPL). The photopolymerization dynamics at and around voxels (volume pixels) were controlled by the combined action of a co-initiator and a radical quencher added into the photoresist. In the second part of the manuscript longitudinal scanning during microfabrication is studied as a method to achieve fast fabrication of hierarchical microstructures with hexahedral unit cells.

Semiconducting quantum dots (QDs) have unique optical properties such as high quantum yields and broad emission spectral wavelengths that are tunable by the quantum confinement effect. Considerable effort directed at modifying the surface of QDs using capping agents have led to a simple solution-based process, the stabilization of QDs, and their uniform dispersion in solvent. Due to these unique properties, quantum dots are of increasing importance in the fundamental studies and in a wide range of technological applications such as optical power limiters, light emitting devices, photovoltaics, lasers, and fluorescent labels for bioimaging. Tacking the full potential of QDs in optoelectronic devices require efficient mechanisms for transfer of energy or electrons produced in the optically excited QDs. We have investigated various organic-inorganic hybrids based on QD-decorated and QD-coupled systems on semiconducting substrates or molecules to achieve energy or charge transfer. The hybridization of p-type π-conjugated molecules to the surface of n-type QDs can induce distinct luminescence and charge transport characteristics due to energy and/or charge transfer effects. These kinds of energy/charge transporting properties are also observable in the perovskite QDs. The novel properties of hybrids consisting of QDs decorated or attached to conducting materials could find applications in molecular electronics and optoelectronics, including luminescent displays and energy harvesting cells.

Laser confocal photoluminescence characteristics for nanostructures using 2D semiconducting MoS2 hybridized with organic semiconductors or perovskite CsPbBr3-quantum-dots (QDs) have been investigated and analyzed in terms of energy and charge transfer effects. Photo-triggered MoS2/rubrene field-effect-transistors (FETs) were operated by light irradiation controlled by gate bias. Mobility and photoresponsivity upon light irradiation for hybrid MoS2/CsPbBr3-QDs-based FETs were enhanced, owing to n-type doping.

In this study, we developed a novel three-dimensional (3D) cancer cell chip using a three-floor hierarchical 3D pyramid structure (3D pyramid) to simulate 3D tumor cell growth in vitro and to detect anticancer drugs. The proposed 3D pyramidbased cancer cell chip offered substantial advantages for the agglomerate formation of tumor cells, in which cells could be maintained as tumor spheroids for up to 3 weeks. Soon after HeLa tumor cells adhered to the micropatterned pillar sidewalls, they were suspended between the pillars based on scanning electron microscopy images. Treatment with the anticancer drug oleanolic acid resulted in 46.33% and 5.86% apoptotic cells on the 2D plate and 3D pyramid-based cell chip, respectively, compared with only 0.06% apoptotic cells in the control. The increase in chemoresistance to anticancer drugs in the 3D pyramid-based cell chip might be a result of cell confluence and hypoxia due to the spheroid formation of tumor cells in the 3D pyramid structure. These results indicated that the proposed cell chip could potentially be used for anticancer drug screening or can be incorporated into other models aimed at prolonging various cell functions in culture.

Biocompatibility is very important for cell growth using 3D printers, but biocompatibility materials are very expensive. In this study, we investigated the possibility of cell culture by the surface modification of relatively low-cost industrial materials and an efficient three-dimensional (3D) scaffold made with an industrial ABS filament for cell proliferation, spheroid formation, and drug screening applications. We evaluated the adequate structure among two-layer square shape 3D scaffolds printed by fused deposition modeling with variable infill densities (10&ndash, 50%). Based on the effects of these scaffolds on cell proliferation and spheroid formation, we conducted experiments using the industrial ABS 3D scaffold (IA3D) with 40% of infill density, which presented an external dimension of (XYZ) 7650 &micro, m &times, 7647 &micro, 210 &micro, m, 29.8% porosity, and 225 homogenous micropores (251.6 &micro, 245.9 &micro, m). In the IA3D, spheroids of cancer HepG2 cells and keratinocytes HaCaT cells appeared after 2 and 3 days of culture, respectively, whereas no spheroids were formed in 2D culture. A gold nanoparticle-coated industrial ABS 3D scaffold (GIA3D) exhibited enhanced biocompatible properties including increased spheroid formation by HepG2 cells compared to IA3D (1.3-fold) and 2D (38-fold) cultures. Furthermore, the cancer cells exhibited increased resistance to drug treatments in GIA3D, with cell viabilities of 122.9% in industrial GIA3D, 40.2% in IA3D, and 55.2% in 2D cultures when treated with 100 &micro, M of mitoxantrone. Our results show that the newly engineered IA3D is an innovative 3D scaffold with upgraded properties for cell proliferation, spheroid formation, and drug-screening applications.

The exciton dynamics in pristine films of two structurally related low-bandgap diketopyrrolopyrrole (DPP)-based donor-acceptor copolymers and the photophysical processes in bulk heterojunction solar cells using DPP copolymer:PC71 BM blends are investigated by broadband transient absorption (TA) pump-probe experiments covering the vis-near-infrared spectral and fs-μs dynamic range. The experiments reveal surprisingly short exciton lifetimes in the pristine poly-mer films in conjunction with fast triplet state formation. An in-depth analysis of the TA data by multivariate curve resolution analysis shows that in blends with fullerene as acceptor ultrafast exciton dissociation creates charge carriers, which then rapidly recombine on the sub-ns timescale. Furthermore, at the carrier densities created by pulsed laser excitation the charge carrier recombination leads to a substantial population of the polymer triplet state. In fact, virtually quantitative formation of triplet states is observed on the sub-ns timescale. However, the quantitative triplet formation on the sub-ns timescale is not in line with the power conversion efficiencies of devices indicating that triplet state formation is an intensity-dependent process in these blends and is reduced under solar illumination conditions, as free charge carriers can be extracted from the photoactive layer in devices.

Dipolar chromophores consisting of electron donor (D) and electron acceptor (A) groups connected through a conjugated π-bridge have been actively studied and integrated in optoelectronic and electronic devices. Generally, such π-conjugated molecules provide substantial delocalization of π-electrons over the molecules. Here, a brief overview of recent research on D-π-A dipolar chromophores including their syntheses and several promising applications is reported, especially in nonlinear optical devices and organic photovoltaics. Structure/property relationships are discussed in order to exploit the potentials by tuning the π-electron density, polarizability, and HOMO-LUMO band gap of the chromophores. Some of the examples may well set the stage for chip-scale integration of optoelectronics as well as the realization of an important array of new device technologies.

Groups around the world are pursuing optoelctronic and magneto-optic properties of graphene-based materials since they hold a lot of promise for future technologies. Quantum dot (QD) decorated graphenic nanohybrids can be candidates for demonstrating energy transfer, while magnetic nanoparticles (MNPs) on graphene give rise to interesting electronic phenomena like magneto-optical effects. Graphene containing MNPs are also good candidates for exploring quantum-hall effect. In medicine these materials have demonstrated applications in bioimaging, drug delivery, photothermal treatment and magnetic resonance imaging. A majority of groups working on QD or MNPs have focused on chemical functionalization methods for making graphene-MNP nanohybrids. We have developed a set of small molecule as well as polymeric ligands for noncovalent self-assembly of nanoparticles on graphene. The ligands contain pyrene as an anchor group for graphene and also thiol or dipamine as anchor groups for QD or MNPs. In this presentation we discuss the synthesis and characterization of these materials and outline some early results regarding exploratory device fabrication involving these materials.

Organic rubrene (5,6,11,12-tetraphenyltetracene) nanorods (NRs) were fabricated through the physical vapor transport method for the study of active fluorescence optical waveguiding and its modulation. The functionalized CdSe/ZnS quantum dots (QDs) with blue and green emissions were partially attached to the surface of the rubrene NR. Using a high resolution laser confocal microscope (LCM), the nanoscale photoluminescence (PL) intensity of the pristine rubrene portion of the hybrid NR/QDs was observed to be considerably enhanced after it was attached with blue (or green) QDs. The nanoscale optical waveguiding characteristics of the hybrid NR/QDs were investigated in terms of the output LCM PL spectra as a function of propagation distance. We observed more efficient optical waveguiding characteristics from the hybrid rubrene NR/blue-QDs than from the pristine NR and the hybrid rubrene NR/green-QDs. These results can be analyzed in terms of the higher Forster resonance energy transfer efficiency for hybrid rubrene NR/blue-QDs system. The results and analysis were supported by a drastic decrease of exciton lifetime of QDs in the hybrid region as measured by time-resolved PL decay curves.

We report the photoelectrochemical photocurrent switching (PEPS) effect in the system based on a C60 derivatives and nanostructured cadmium sulfide. Rapid and efficient photocurrent switching upon changes of the electrode potential was observed. This process relies on the photocurrent generation by semiconducting particles and interfacial electron transfer reactions governed by the redox chemistry of fullerene derivatives (fullerene–oligothiophene dyads) with molecular oxygen as a final electron acceptor. Surprisingly, fullerene derivatives without thiophene moieties were much less efficient as CdS modifiers. These peculiar photoelectrochemical properties were applied for construction of an optoelectronic logic device.

Hybrids consisting of CdSe/ZnS quantum dot (QD) as a core and thiol-group functionalized poly(3-hexylthiophene) (P3HT) as a shell were fabricated using the ligand-exchange method. We clearly observed the photovoltaic characteristics of a single QD-P3HT hybrid by using conducting atomic force microscopy. Monochromatic power conversion efficiency drastically increased with an increase in the molecular weight (Mw) of P3HT, suggesting sufficient photoinduced charge transfer between the QD and highly ordered P3HT chains. The nanoscale photoluminescence (PL) intensity for a single QD considerably decreased with increasing Mw of P3HT owing to charge transfer effects. On the basis of time-resolved PL and transient absorption spectra measurements of the QD-P3HT hybrids, we deduced that the exciton lifetimes of the QD were reduced with higher-Mw P3HT hybrids, and photobleaching was observed. The measured nanoscale optical characteristics of the single QD-P3HT hybrids support their distinct photovoltaic behaviors.

Silicon solar cells mainly absorb visible light, although the sun emits ultraviolet (UV), visible, and infrared light. Because the surface reflectance of a textured surface with SiNX film on a silicon solar cell in the UV wavelength region (250-450 nm) is higher than ∼27%, silicon solar-cells cannot effectively convert UV light into photo-voltaic power. We implemented the concept of energy-down-shift using CdSe/ZnS core/shell quantum-dots (QDs) on p-type silicon solar-cells to absorb more UV light. CdSe/ZnS core/shell QDs demonstrated clear evidence of energy-down-shift, which absorbed UV light and emitted green-light photoluminescence signals at a wavelength of 542 nm. The implementation of 0.2 wt% (8.8 nm QDs layer) green-light emitting CdSe/ZnS core/shell QDs reduced the surface reflectance of the textured surface with SiNX film on a silicon solar-cell from 27% to 15% and enhanced the external quantum efficiency (EQE) of silicon solar-cells to around 30% in the UV wavelength region, thereby enhancing the power conversion efficiency (PCE) for p-type silicon solar-cells by 5.5%.

Organic p – n junction nanoparticles (NPs) of p -type poly(3-hexylthiophene) (P3HT) and n -type [6,6]-phenyl C 61 -butyric acid methyl ester (PCBM) with approximate diameters of 80–250 nm were fabricated by a mini-emulsion method. Various concentrations of functionalized CdSe/ZnS quantum dots (QDs) were hybridized with P3HT/PCBM NPs. The photoluminescence (PL) spectra of the QDs mostly overlapped the absorption spectra of the P3HT/PCBM NPs, suggesting the activation of energy and/or charge-transfer effects. Using a high-resolution laser confocal microscope (LCM), we observed that the LCM PL intensity of a single P3HT/PCBM NP quenched with increasing QD concentration. Conducting atomic force microscopy revealed that the photocurrent of the P3HT/PCBM NP was enhanced as the QD concentration increased. After the hybridization of the P3HT/PCBM NPs with the QDs, the energy/charge-transfer effects and the charge dissociation of excitons with incident light have been more active, resulting in the increased photocurrent.

Organic field effect transistors (OFETs) were fabricated using a p-type rubrene single nanosheet (NS) as an active layer hybridized with n-type CdSe/ZnS quantum dots (QDs). The dark and photoresponsive ( λ ex = 455 nm) electrical characteristics of the rubrene NS-based OFETs were investigated with and without the QDs. In dark conditions, the source-drain current ( I DS ) of the OFETs increased and the threshold voltage was shifted to a positive direction after the partial attachment of the QDs to the surface of the NS. We also observed that the laser confocal microscope (LCM) PL intensity of the rubrene NS decreased through the attachment of the QDs, due to the charge transfer effect. With light irradiation, the photoresponsive I DS and mobility of the OFETs were considerably enhanced by the hybridization with QDs. The results originated from both the ground charge transfer and exciton dissociation effects at the interface of p-type rubrene and n-type QDs heterojunctions.

Nanometer-scale optical waveguides are attractive due to their potential applicability in photonic integration, optoelectronic communication, and optical sensors. Nanoscale white light-emitting and/or polychromatic optical waveguides are desired for miniature white-light generators in microphotonic circuits. Here, polychromatic (i.e., blue, green, and red) optical waveguiding characteristics are presented using a novel hybrid composite of highly crystalline blue light-emitting organic nanowires (NWs) combined with blue, green, and red CdSe/ZnS quantum dots (QDs). Near white-color waveguiding is achieved for organic NWs hybridized with green and red QDs. Light, emitted from QDs, can be transferred to the organic NW and then optically waveguided through highly packed π-conjugated organic molecules in the NW with different decay characteristics. Remote biosensing using dye-attached biomaterials is presented by adapting the transportation of QD-emitted light through the organic NW.

Vibrational properties of two fullerene derivatives: C60TZ-OT-5 (1) and C60TH-3HX (2) have been studied using infrared absorption and Raman scattering spectroscopies. Additionally, quantum chemical calculations of the equilibrium geometry and normal mode vibrations of these functionalized fullerenes were performed. It was stated that despite of distinct structural differences between the investigated molecules, their experimental spectra are quite similar and correspond well with the calculated ones. The orientation of the molecules in the Langmuir–Blodgett films was evaluated.

Hybrid nanowires (NWs) of light-emitting poly(3-hexylthiophene) (P3HT) blended with gold nanoparticles (Au-NPs) were fabricated by a wetting method. The functionalized CdSe/ZnS quantum dots (QDs) were attached to the surfaces of P3HT/Au-NPs NWs. The nanoscale photoluminescence (PL) characteristics of the P3HT, P3HT/Au-NPs, and QDs/P3HT/Au-NPs single NWs were investigated using a high resolution laser confocal microscope (LCM). For a P3HT/Au-NPs single NW, the LCM PL intensity of the P3HT NW decreased due to the luminescence quenching effect by the blending with Au-NPs. However, the LCM PL intensity of the P3HT/Au-NPs NW drastically increased when the QDs were attached to the surface of the NW. The PL enhancement of the P3HT NW part in the hybrid QDs/P3HT/Au-NPs single NW originated from the Forster resonance energy transfer (FRET) effect between the QDs and the P3HT NW, which was assisted by the surface plasmon (SP) coupling of Au-NPs with the QDs. Based on the analysis of time-resolved PL spectra, the exciton lifetimes of the QDs for the QDs/P3HT/Au-NPs NW were found to decrease considerably in comparison with those of the QDs/P3HT NWs without Au-NPs. We also found that the energy transfer rate of the QDs/P3HT NW increased from 0.76 to 0.93 with the Au-NPs. These observations support the notion of SP assisted FRET effect in hybrid nanosystems.

A silicon carbonitride (SICN) ceramic microrobot, biocompatible and magnetically activable, is developed for the delivery of viable cells to defective tissue by sequential steps of microstructuring, magnetization, and cell loading. The ceramic carrier of porous cylindrical framework is fabricated by 3D laser lithography using a photocurable preceramic polymer, chemically modified polyvinylsilazane, and subsequent pyrolysis at 600 °C under an inert atmosphere. Magnetic nanoparticles (MNP) are integrated into the surface-modified ceramic carrier by thiol-ene click reaction. Finally, the microrobot is loaded with fibroblast cells, which can be guided by a rotating external magnetic field. The proposed ceramic microrobot is mechanically durable, adequately controllable with external magnetic field, and quite compatible with mammalian cells.