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Exploring structural phase transitions and luminescence mechanisms in Zero-dimensional (0D) metal halides poses significant challenges, that are crucial for unlocking the full potential of tunable optical properties and diversifying their functional capabilities. Herein, we have designed two inter-transformable 0D Cu(I)-based metal halides, namely (C19H18P)2CuI3 and (C19H18P)2Cu4I6, through distinct synthesis conditions utilizing identical reactants. Their optical properties and luminescence mechanisms were systematically elucidated by experiments combined with density functional theory calculations. The bright cyan-fluorescent (C19H18P)2CuI3 with high photoluminescence quantum yield (PLQY) of 77% is attributed to the self-trapped exciton emission. Differently, the broad yellow-orange fluorescence of (C19H18P)2Cu4I6 displays a remarkable PLQY of 83%. Its luminescence mechanism is mainly attributed to the combined effects of metal/halide-to-ligand charge transfer and cluster-centered charge transfer, which effects stem from the strong Cu-Cu bonding interactions in the (Cu4I6)2- clusters. Moreover, (C19H18P)2CuI3 and (C19H18P)2Cu4I6 exhibit reversible structural phase transitions. The elucidation of the phase transitions mechanism has paved the way for an unforgeable anti-counterfeiting system. This system dynamically shifts between cyan and yellow-orange fluorescence, triggered by the phase transitions, bolstering security and authenticity. This work enriches the luminescence theory of 0D metal halides, offering novel strategies for optical property modulation and fostering optical applications., (© 2024 Wiley‐VCH GmbH.)

Zn-I 2 batteries have attracted attention due to their low cost, safety, and environmental friendliness. However, their performance is still limited by the irreversible growth of Zn dendrites, hydrogen evolution reactions, corrosion, and shuttle effect of polyiodide. In this work, we have prepared a new porous polymer (CD-Si) by nucleophilic reaction of β-cyclodextrin with SiCl 4 , and CD-Si is applied to the solid polymer electrolyte (denoted PEO/PVDF/CD-Si) to solve above-mentioned problems. Through the anchoring of the CD-Si, a conductive network with dual transmission channels was successfully constructed. Due to the non-covalent anchoring effect, the ionic conductivity of the solid polymer electrolytes (SPE) can reach 1.64×10 -3  S cm -1 at 25 °C. The assembled symmetrical batteries can achieve highly reversible dendrite-free galvanizing/stripping (stable cycling for 7500 h at 5 mA cm -2 and 1200 h at 20 mA cm -2 ). The solid-state Zn-I 2 battery shows an ultra-long life of over 35,000 cycles at 2 A g -1 . Molecular dynamics simulations are performed to elucidate the working mechanism of CD-Si in the polymer matrix. This work provides a novel strategy towards solid electrolytes for Zn-I 2 batteries., (© 2023 Wiley-VCH GmbH.)

Although significant achievements in improving the stability of MoS 2 anodes have been made, the cycling life in most studies is still less than 1000 cycles. This is because MoS 2 anodes directly contact the electrolyte and generate byproducts, leading to the loss of active mass and capacity decay. Herein, the inner-outer dual space protection of MoS 2 fibers is realized by regulating the surface and interface structure of electrospinning precursors (noted as X-MoS 2 /CNFs). Inside the fibers, Mo-N covalent bond is constructed to anchor the active material, preventing MoS 2 from falling off the matrix after multiple cycles. Simultaneously, surface of the fibers, a stable solid electrolyte interface layer is induced to prevent contact between active materials and electrolytes. In addition, the initial Coulombic efficiency is enhanced as high as 84.4%. The profound investigations of morphological evolution and internal real-time resistance confirm the double structural protection of 800-MoS 2 /CNFs. As a result, a decent cycling performance (408.9 mAh g -1 at 1000 mA g -1 for 2000 cycles) and the satisfied rate capacities (100-1000 mA g -1 ) are achieved. This work provides a new idea for the preparation of stable anodes for alkali metal ion secondary batteries., (© 2023 IOP Publishing Ltd.)

Improving imaging quality and reducing time consumption are the key problems that need to be solved in the practical application of ghost imaging. Hence, we demonstrate a double filter iterative ghost imaging method, which adopts the joint iteration of projected Landweber iterative regularization and double filtering based on block matching three dimensional filtering and guided filtering to achieve high-quality image reconstruction under low measurement and low iteration times. This method combines the advantages of ill-posed problem solution of projected Landweber iterative regularization with double filtering joint iterative de-noising and edge preservation. The numerical simulation results show that our method outperforms the comparison method by 4 to 6 dB in terms of peak signal-to-noise ratio for complex binary target 'rice' and grayscale target 'aircraft' after 1500 measurements. The comparison results of experiments and numerical simulations using similar aircraft targets show that this method is superior to the comparison method, especially in terms of richer and more accurate edge detection results. This method can simultaneously obtain high quality reconstructed image and edge feature information under low measurement and iteration times, which is of great value for the practical application fields of imaging and edge detection at the same time, such as intelligent driving, remote sensing and other fields.

Objective: Endometrial carcinoma (EC) is one of the most common malignancies leading to death in women and poses a serious threat to women's health. Therefore, exploring the molecular mechanisms affecting EC progression and metastasis is a clinical research hotspot. It has been shown that lncRNAs play an important role in the pathogenesis of EC. It is important to investigate the role of lncRNAs in the growth of EC to improve diagnosis and find new therapeutic targets of EC., Methods: The expression of LINC00936 in 36 EC tissues, paracancerous tissues, and cell lines was measured by fluorescence quantitative PCR. The relationship between LINC00936 expression and clinicopathological characteristics of patients was analyzed. The effects of overexpression of LINC00936 on proliferation, invasion, and migration of EC cells were examined by CCK-8 and transwell assays. Colony formation assay was also performed to evaluate the colony forming ability of EC cells. The effect of overexpression of LINC00936 on the expression of EMT-related proteins in EC cells was examined by western blot. In addition, the effect of LINC00936 overexpression on the growth of EC in vivo was examined by using tumorigenicity assay in the nude mouse., Results: LINC00936 was expressed at a low level in EC tissues and cell lines and significantly correlated with tumor size and lymphatic metastasis of patients. Overexpression of LINC00936 significantly inhibited the proliferation, invasion, and migration, as well as colony formation ability of EC cells. Western blot analysis showed that overexpression of LINC00936 significantly promoted the expression of E-cadherin and inhibited the expression of N-cadherin and vimentin in EC cells. Tumorigenic assays in the nude mouse demonstrated that overexpression of LINC00936 inhibited the growth of EC in vivo by suppressing Ki-67 and promoting E-cadherin expression., Conclusion: LINC00936 was expressed at a low level in EC tissues and significantly correlated with tumor size and lymphatic metastasis of patients. Overexpression of LINC00936 significantly inhibited the proliferation, invasion, and migration, as well as colony formation ability of EC cells. Therefore, LINC00936 could be a new target for the early diagnosis and treatment of EC patients., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Haizhu Sun and Peiling Li.)

The high photogenerated carrier recombination rate and the low visible light utilization limit the development of graphitic carbon nitride (CN) in industrial photocatalytic H 2 generation. Herein, 1T-phase MoS 2 nanoparticles with high conductivity and more active sites are in-situ grown on B-doped carbon nitride (CNB) nanosheets through a one-step hydrothermal method. The doping of boron element effectively improves the harvesting visible light ability by tuning the energy gap, while the introduction of 1T-phase MoS 2 successfully increases the carrier transfer rate by suppressing charge trapping. An optimized H 2 production activity of 5334 μmol h -1  g -1 with the apparent quantum efficiency of 10.2% is achieved by 1T-MoS 2 /CNB sample, which is 167 times higher than that of pure CN. The mechanism is systematically illustrated by the combination of DFT calculations and transient absorption measurements. This work provides a new way for the construction of transition metal-derived co-catalysts in photocatalytic hydrogen energy storage., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: MIAT (myocardial infarction-associated transcript) regulates cell proliferation, apoptosis, and metastasis in several cancers. In this study, the authors aimed to explore the role of MIAT in ovarian cancer. Materials and Methods: The expression of MIAT in ovarian cancer subtypes, normal human ovarian surface epithelial and ovarian cancer cell lines was measured by qualitative real-time polymerase chain reaction (qRT-PCR). OVCAR3 and SKOV3 cells were transfected with MIAT overexpression plasmid or siMIAT. The cell growth ability was then evaluated by CCK-8 and colony formation assays. The cell migration and invasion rate were separately measured by wound-healing and transwell assays. The levels of epithelial-mesenchymal transition (EMT)-associated markers were evaluated by Western blotting. MIAT sponging miR-150-5p was predicted by starBase and confirmed by dual-luciferase reporter assays. The expression of miR-150-5p in OVCAR3 and SKOV3 cells with MIAT overexpression or knockdown, and in ovarian cancer subtypes was also measured by qRT-PCR. Further analyses confirmed the role of MIAT sponging miR-150-5p in ovarian cancer cells. Results: MIAT was highly expressed in mesenchymal subtype ovarian cancer tissues and ovarian cancer cells. In OVCAR3 and SKOV3 cells, overexpression of MIAT promoted, and knockdown of MIAT suppressed the cell growth, migration, invasion, and EMT. miR-150-5p was sponged and regulated by MIAT. miR-150-5p was downregulated in mesenchymal subtype ovarian cancer. Suppression of cell migration, invasion, and EMT caused by miR-150-5p overexpression was rescued by MIAT overexpression. Conclusions: MIAT acts as an oncogene in ovarian cancer cells through sponging miR-150-5p. MIAT or miR-150-5p expression might be a potential prognostic biomarker for ovarian cancer patients. MIAT and miR-150-5p are potential therapeutic targets in treatment of ovarian cancer.

Black phosphorus nanoparticles (BP NPs) possess great advantages in photocatalysis owing to the rich surface active sites, extremely high carrier mobility, and strong visible-near-infrared light response. However, the complex preparation process, poor stability, and rapid carrier recombination restrict their successful application in photocatalysis. Herein, the above problems are resolved by preparing BP NPs through a facile sonication-assisted hydrothermal method. To further improve the stability and photocatalytic activity, BP NPs are tightly anchored onto ZnS to prepare ZnS-BP porous nanosheets. With the Zn-P coordination bond built between them, higher stability, enhanced carrier transport ability, and excellent hydrogen adsorption and desorption equilibrium of photocatalysts are achieved. An efficient and recyclable photocatalytic hydrogen evolution rate of 1561 μmol h -1 g -1 is obtained under visible-light irradiation, which is superior to that of previously reported BP-based photocatalysts. Besides, the photocatalytic mechanism is investigated based on the theoretical calculations and experimental characterizations. The charge transfer dynamics are studied by surface photovoltage (SPV), ultrafast transient absorption (TA), X-ray absorption spectra (XAS), electrochemical impedance spectroscopy (EIS), and steady-state photoluminescence (PL) spectra. This work set a reference for the design of high-performance BP-related nanomaterials in solar energy storage and conversion.

Water soluble nanocrystals (NCs) are promising materials in aqueous-processed solar cells because of their high extinction coefficient, low-cost, and favorable photoelectric characteristics. However, the power conversion efficiency (PCE) of the present aqueous-processed NC solar cells is restricted by the short depletion region of the active layer and limited Fermi level offset between NCs and the electron transport layer. Herein, these issues are effectively addressed by preparing Cd x Zn 1- x Te NCs capped with 2-aminoethanethiol hydrochloride. The introduction of Zn 2+ into CdTe NCs widens the Fermi level offset from 0.68 to 0.74 eV, lengthens the depletion region from 130 to 137 nm, and hence brings obvious improvement in the open circuit voltage (V oc ) and fill factor. Especially, the depletion region is successfully tuned from 137 to 171 nm, and even lengthened to a record thickness of 200 nm based on aqueous-processed solar cells. As a result, a champion thickness ratio (74%) of depletion region to active layer (200/270 nm) is achieved. A champion PCE of 5.96% and short-circuit current (J sc ) of 21.2 mA cm -2 are achieved among aqueous-processed NC solar cells. This work provides a simple way to prepare polynary NCs and highlights a prospective method to develop more efficient and cost-effective solution-processed environment friendly solar cells., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Photothermal therapy (PTT) is successfully integrated with photodynamic therapy (PDT) to effectively improve the curative effect of cancer. The therapy nanoplatform is based on hollow Pd (H-Pd) nanospheres conjugated with Ce6 (Pd@Ce6). H-Pd nanospheres and Ce6 work as PTT and PDT agents, respectively. The H-Pd nanospheres with tunable surface plasmon resonance (SPR) properties effectively absorb light with near-infrared (NIR) emission and then convert the light to heat, selectively killing tumor cells. The experimental results show that H-Pd nanospheres with a size of 90 nm have the strongest absorbance and exhibit a high photothermal conversion efficiency (η) of 70%. Moreover, the absorption intensity and photothermal properties of H-Pd nanospheres do not show any decrease after 6 months of storage at room temperature, showing their excellent stability. Furthermore, after Ce6 is conjugated onto the surface of H-Pd nanospheres using polyethylenimine (PEI) as a linker, Pd@Ce6 not only exhibits the capabilities of photothermal conversion but also generates singlet oxygen ( 1 O 2 ), realizing the integration of PDT and PTT. In cell experiments, 86% of HeLa cells are killed after Pd@Ce6 is simultaneously irradiated with 660 and 808 nm lasers for 5 min with a power of 0.5 and 2 W cm -2 , respectively. This successful combination of PTT with PDT to eradicate cancer provides a noninvasive and harmless way for cancer therapy.

As important anodes in lithium-ion batteries, graphene is always faced with the aggregation problem that makes most of the active sites lose their function at high current densities, resulting in low Li-ion intercalation capacity and poor rate performance. To address this issue, a layered g-C 3 N 4 @reduced graphene oxide composite (g-C 3 N 4 @RGO) was prepared via a scalable and easy strategy. The resultant g-C 3 N 4 @RGO composite possesses large interlayer distances, rich N-active sites, and a microporous structure, which largely improves Li storage performance. It shows excellent cycle stability (899.3 mA h g -1 after 350 cycles under 500 mA g -1 ) and remarkable rate performance (595.1 mA h g -1 after 1000 cycles under 1000 mA g -1 ). Moreover, the g-C 3 N 4 @RGO electrode exhibits desired capacity retention and relatively high initial Coulombic efficiency of 58.8%. Impressively, this result is better than that of RGO (29.1%) and most of RGO-based anode materials reported in the literature. Especially, the g-C 3 N 4 @RGO-based electrode is enough to power two tandem red-light-emitting diodes and run a digital watch. Interestingly, the electronic watch can work continuously for more than 20 days. This novel strategy shows the great potential of g-C 3 N 4 @RGO composites as energy-storage materials.

A novel kind of biomass-derived, high-oxygen-containing carbon material doped with nitrogen that has willow-leaf-shaped pores was synthesized. The obtained carbon material has an exotic hierarchical pore structure composed of bowl-shaped macropores, willow-leaf-shaped pores, and an abundance of micropores. This unique hierarchical porous structure provides an effective combination of high current densities and high capacitance because of a pseudocapacitive component that is afforded by the introduction of nitrogen and oxygen dopants. Our synthetic optimization allows further improvements in the performance of this hierarchical porous carbon (HPC) material by providing a high degree of control over the graphitization degree, specific surface area, and pore volume. As a result, a large specific surface area (1093 m 2 g -1 ) and pore volume (0.8379 cm 3 g -1 ) are obtained for HPC-650, which affords fast ion transport because of its short ion-diffusion pathways. HPC-650 exhibits a high specific capacitance of 312 F g -1 at 1 A g -1 , retaining 76.5% of its capacitance at 20 A g -1 . Moreover, it delivers an energy density of 50.2 W h kg -1 at a power density of 1.19 kW kg -1 , which is sufficient to power a yellow-light-emitting diode and operate a commercial scientific calculator.

A facile and efficient copper-catalyzed azidative multifunctionalization of alkynes has been developed by using N-fluorobenzenesulfonimide (NFSI) as both nitrogen source and aryl source and trimethylsilyl azide (TMSN 3 ) as azido source. This transformation proceeds under mild conditions, providing a series of α-azido-α-aryl imine in good yields by a single operation starting from a wide range of alkynes. The prepared α-azido-α-aryl imines could be easily converted into 1,5-piperizine-fused 1,2,3-triazoles and azido enamines.

Whereas organic-inorganic hybrid perovskite nanocrystals (PNCs) have remarkable potential in the development of optoelectronic materials, their relatively poor chemical and colloidal stability undermines their performance in optoelectronic devices. Herein, this issue is addressed by passivating PNCs with a class of chemically addressable ligands. The robust ligands effectively protect the PNC surfaces, enhance PNC solution processability, and can be chemically addressed by thermally induced crosslinking or radical-induced polymerization. This thin polymer shield further enhances the photoluminescence quantum yields by removing surface trap states. Crosslinked methylammonium lead bromide (MAPbBr 3 ) PNCs are applied as active materials to build light-emitting diodes that have low turn-on voltages and achieve a record luminance of over 7000 cd m -2 , around threefold better than previous reported MA-based PNC devices. These results indicate the great potential of this ligand passivation approach for long lifespan, highly efficient PNC light emitters., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel two-step solution approach is put forward to design a unique three dimensional (3D) porous ZnO-SnS p-n heterojunction under mild conditions. This special 3D structure is induced via flower-like ZnO in which SnS serves as an efficient photosensitizer to improve the light harvesting across the whole visible range. A profound investigation of the mechanism shows that this 3D porous ZnO-SnS material effectively integrates the large surface area and high redox potential of ZnO, and wide visible-light harvesting of SnS, which largely promotes the transfer and separation rate of carriers. The systematic study on the active species generated during the photocatalysis illustrates that it is the photoelectrons, ˙OH and O 2 ˙ - that play the crucial role in the degradation of dyes. As a result, the noble-metal free photocatalyst degrades nearly 100% of rhodamine B (RhB) within 80 min and methylene blue (MB) in 40 min under visible light. The photocatalytic activity is 10 times higher than that of the pure flower-like ZnO and two times higher than that of the SnS material. Moreover, the photocatalyst is easily separated and reused at least four times without obvious change in efficiency and properties. This work provides an effective strategy for the synthesis of 3D porous p-n heterojunction semiconductor-based photocatalysts with low cost and low toxicity, which present promising applications in the field of solar energy storage and conversion.

The epithelial-mesenchymal transition (EMT) is one of the crucial procedures for cancer invasion and distal metastasis. Despite undergoing intensive studies, the mechanisms underlying EMT remain to be completely elucidated. Here, we identified that apoptosis-stimulating protein of p53-2 (ASPP2) is a novel target of MiR-205 in various cancers. Interestingly, the binding site of MiR-205 at the 3'-untranslated region of ASPP2 was highly conserved among different species. An inverse correlation between MiR-205 and ASPP2 was further observed in vivo in cervical cancers, suggesting MiR-205 may be an important physiological inhibitor of ASPP2. Hypoxia is a hallmark of solid tumor microenvironment and one of such conditions to induce EMT. Notably, MiR-205 was remarkably induced by hypoxia in cervical and lung cancer cells. A marked suppression of ASPP2 was observed simultaneously. Further studies confirmed that hypoxia-induced ASPP2 suppression was mainly attributed to the elevated MiR-205. Interestingly, the alteration of MiR-205/ASPP2 under hypoxia was accompanied with the decreased epithelial marker E-cadherin and increased mesenchymal marker Vimentin, as well as a morphological transition from the typical cobblestone-like appearance to the mesenchymal-like structure. More importantly, MiR-205 mimics or ASPP2 silencing similarly promoted EMT process. By contrast, ASPP2 recovery or MiR-205 inhibitor reversed MiR-205-dependent EMT. Further studies demonstrated that the newly revealed MiR-205/ASPP2 axis promoted cell migration and also increased cell proliferation both in vivo and in vitro. These data together implicated a critical impact of MiR-205/ASPP2 on promoting EMT. MiR-205/ASPP2 may be potential diagnostic and therapeutic biomarkers in cervical and lung cancers.

A novel kind of hybrid solar cell (HSC) was developed by introducing water-soluble insulating polymer poly(vinyl alcohol) (PVA) into nanocrystals (NCs), which revealed that the most frequently used conjugated polymer could be replaced by an insulating one. It was realized by strategically taking advantage of the characteristic of decomposition for the polymer at annealing temperature, and it was interesting to discover that partial decomposition of PVA left behind plenty of pits on the surfaces of CdTe NC films, enlarging surface contact area between CdTe NCs and subsequently evaporated MoO3. Moreover, the residual annealed PVA filled in the voids among spherical CdTe NCs, which led to the decrease of leakage current. An improved shunt resistance (increased by ∼80%) was achieved, indicating the charge-carrier recombination was effectively overcome. As a result, the new HSCs were endowed with increased Voc, fill factor, and power conversion efficiency compared with the pure NC device. This approach can be applied to other insulating polymers (e.g., PVP) with advantages in synthesis, type, economy, stability, and so on, providing a novel universal cost-effective way to achieve higher photovoltaic performance.

By using N-fluorobenzenesulfonimide as both the oxidant and the amination reagent, we have realized the first example of the intermolecular chalcogenative amination of alkynes, which grants facile, highly regio- and stereoselective access to chalcogenated enamides. The reaction features mild conditions, high yields and selectivities, remarkably broad substrate scope, and excellent functional group tolerance. Mechanistic studies indicate the in situ generated chalcogen imidates to be the actual reactive species, which in turn, has clarified the mechanism of related transformations. These reactions represent significant additions to the development of the highly selective amino bisfunctionalization of alkynes., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: The aim of the present study was to examine the apoptosis-promoting effects and mechanisms of hematoporphyrin monomethyl ether (HMME)-sonodynamic therapy (SDT) on endometrial cancer cells in vitro., Methods: Endometrial cancer cell samples were divided into four groups: 1) untreated control group, 2) HMME group, 3) pure ultrasound group, and 4) HMME combined with ultrasound, i.e. SDT group. CCK-8 method was utilized to assess the inhibiting effect of SDT on the proliferation of endometrial cancer cells. Optical microscope and field emission transmission electron microscopy were used to characterize the morphology changes of the cancer cells induced by the treatments. Apoptosis rate, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were examined by flow cytometer. Fluorescence intensity measured by laser scanning confocal microscopy was used to explore the variation of intracellular calcium ion (Ca2+) concentration. Apoptosis-related proteins involved in both intrinsic and extrinsic apoptosis signallings were analyzed by western blot., Results: SDT can effectively induce the apoptosis of endometrial cancer cells. Compared with ultrasound which is known as an effective anti-tumor method, SDT leads to a significant improvement on suppression of cell viability and induction of apoptosis, together with more remarkable modifications on the morphology and substructure in both ultrasound sensitive and resistant endometrial cancer cells. Further studies reveals that SDT promotes ROS production, induces loss of MMP and increases intracellular Ca2+ concentration more efficiently than HMME or ultrasound alone. SDT groups also show a rather high expression of apoptosis-promoting proteins, including Bax, Fas and Fas-L, and a significant low expression of apoptosis-suspending proteins including Bcl-2 and Survivin. Meanwhile, both cleaved caspse-3 and caspase-8 are dramatically enhanced in SDT groups. Multiple pathways has been proposed in the process, including the intrinsic activation by excessive ROS and overloaded Ca2+, silencing survivin gene, and the extrinsic pathway mediated by the death receptor., Conclusion: Given its considerable effectivity in both ultrasound sensitive and resistant cells, SDT may therefore be a promising therapeutic method for treating endometrial cancers.

The excellent electrochemical performance of greigite (Fe3S4) coupled with its vast abundance and low toxicity make it a good prospect as an anode material for lithium ion batteries (LIBs). In this research, a simple and feasible approach for producing pure phase, small sized, shape-controllable, and stable Fe3S4 nanoplates (NPs) through hot injection of sulfur solution into Fe(iii) solution was demonstrated. The growth of Fe3S4 NPs involves the primary formation of a pyrite (FeS2) nucleus and subsequent Fe(iii) doping. The lateral size of the Fe3S4 NPs was controlled further by tuning the experimental variable-dependent reactivity of Fe sources in the nucleation and growth stage. The Fe3S4 NPs embedded in LIBs present a low electrochemical resistance and are highly active in lithiation/delithiation processes.

Efficient phosphorescent orange, blue and white organic light-emitting devices (OLEDs) with non-doped emissive layers were successfully fabricated. Conventional blue phosphorescent emitters bis [4,6-di-fluorophenyl]-pyridinato-N,C(2')] picolinate (Firpic) and Bis(2,4-difluorophenylpyridinato) (Fir6) were adopted to fabricate non-doped blue OLEDs, which exhibited maximum current efficiency of 7.6 and 4.6 cd/A for Firpic and Fir6 based devices, respectively. Non-doped orange OLED was fabricated utilizing the newly reported phosphorescent material iridium (III) (pbi)₂Ir(biq), of which manifested maximum current and power efficiency of 8.2 cd/A and 7.8 lm/W. The non-doped white OLEDs were achieved by simply combining Firpic or Fir6 with a 2-nm (pbi)₂Ir(biq). The maximum current and power efficiency of the Firpic and (pbi)₂Ir(biq) based white OLED were 14.8 cd/A and 17.9 lm/W.

We present an economical route to achieve an all-solution and vacuum-deposition free device for fabrication of both the photoactive layer and the electrode. This low cost strategy offers a wide range of possibilities in terms of chemical and physical properties for the fabrication of tailor-made materials and their devices.

The biocompatibility of biomaterials is essentially for its application. The aim of current study was to evaluate the biocompatibility of poly(lactic-co-glycolic acid) (PLGA)/gelatin/nanohydroxyapatite (n-HA) (PGH) nanofibers systemically to provide further rationales for the application of the composite electrospun fibers as a favorable platform for bone tissue engineering. The PGH composite scaffold with diameter ranging from nano- to micrometers was fabricated by using electrospinning technique. Subsequently, we utilized confocal laser scanning microscopy (CLSM) and MTT assay to evaluate its cyto-compatibility in vitro. Besides, real-time quantitative polymerase chain reaction (qPCR) analysis and alizarin red staining (ARS) were performed to assess the osteoinductive activity. To further test in vivo, we implanted either PLGA or PGH composite scaffold in a rat subcutaneous model. The results demonstrated that PGH scaffold could better support osteoblasts adhesion, spreading, and proliferation and show better cyto-compatibility than pure PLGA scaffold. Besides, qPCR analysis and ARS showed that PGH composite scaffold exhibited higher osteoinductive activity owing to higher phenotypic expression of typical osteogenic genes and calcium deposition. The histology evaluation indicated that the incorporation of Gelatin/nanohydroxyapatite (GH) biomimetics could significantly reduce local inflammation. Our data indicated that PGH composite electrospun nanofibers possessed excellent cyto-compatibility, good osteogenic activity, as well as good performance of host tissue response, which could be versatile biocompatible scaffolds for bone tissue engineering.

Cadmium-based quantum dots (QDs) have the advantage of broad UV excitation, narrow emission, bright photoluminescence (PL), and high photostability, which make them fine applications in bio-imaging, electroluminescence (EL) and photovoltaic (PV) devices, catalytic hydrogen production, sensors, etc. This review article summarizes the synthetic methods such as organometallic and aqueous approaches, and the techniques employed to prepare high-quality QDs including microwave, hydrothermal, and ultrasound. QDs and their applications are emphasized for their unique properties, especially in the preparation of near infrared (NIR). Moreover, the synthesis of novel cadmium-based QDs with metal chalcogenide complexes (MCCs) as ligands has been introduced, which can overcome traditional QDs' disadvantages of poor interparticle coupling and conducting. Following the synthetic methods, the latest development of surface modification is summarized, which is important and necessary for the applications of QDs.

Recently, researchers have paid much attention to the toxicity of QDs because of their rapidly increasing application in biomedicine. Recent investigations have indicated that QDs have influences on biological systems at the cellular, subcellular, and protein levels during the processes of imaging and therapeutic applications. The toxicity of QDs is related to their composition, surface functionality, size, shape, and charge, etc. among which composition and surface modification are two important elements. This feature article mainly concentrates on the latest developments in reducing QD toxicity by manipulating their composition and surface modification. Besides the cadmium-based QDs, the assessment of toxicity in vitro and in vivo for other QDs such as carbon dots, graphene QDs, silicon QDs, Ag 2 Se QDs, CuInS 2 @ZnS, InP QDs, hybrid QDs of carbon and CdSe@ZnS, etc., is generalized. Each kind of QD has its own advantages. Cadmium-based QDs have broad UV excitation, narrow emission and bright photoluminescence (PL), while cadmium-free ones present low toxicity. In fact, a lot of investigations show that the toxicity of QDs is dose dependent, whatever the composition. Consequently, surface modification becomes very important to reduce toxicity and simultaneously impart biocompatibility, stability, and specificity to QDs. Therefore, the functionalization of QDs with inorganic shells (e.g., CdSe@ZnS, CdSe@SiO 2 ), polymers, bio- or natural macromolecules is summarized. Future research work should concentrate on preparing novel QDs with appropriate surface modification and investigating the long-term influence of QDs on absorption, distribution, metabolism, and elimination in vivo, especially for cadmium-free QDs such as carbon-based QDs, Ag 2 Se QDs, CuInS 2 @ZnS QDs and InP QDs, etc.

Simvastatin is considered as a stimulator for bone formation. However, the half-life for simvastatin is generally 2 hours, which means, it is difficult to maintain biologically active simvastatin in vivo. To overcome this limitation, we created a system to slowly release simvastatin in vitro and in vivo. We constructed a poly(lactic-co-glycolic acid)/hydroxyapatite nano-fibrous scaffold to carry simvastatin. Releasing assays showed that simvastatin was released from poly(lactic-co-glycolic acid)/hydroxyapatite/simvastatin quickly within - 15 days, and small amounts continued to be released through day 56 (experiments terminated). MTT assays demonstrated that both poly(lactic-co-glycolic acid)/hydroxyapatite and poly(lactic-co-glycolic acid)/hydroxyapatite/simvastatin promoted MC3T3-E1 cell proliferation. However, Alkaline phosphatase assays showed that only poly(lactic-co-glycolic acid)/hydroxyapatite/simvastatin scaffold significantly promoted the osteogenic differentiation of MC3T3-E1 cells in vitro on day 14. To further test in vivo, we created calvaria bone defect models and implanted either poly(lactic-co-glycolic acid)/hydroxyapatite or poly(lactic-co-glycolic acid)/hydroxyapatite/simvastatin. After 4 or 8 weeks post-implantation, the results indicated that poly(lactic-co-glycolic acid)/hydroxyapatite/simvastatin scaffold induced bone formation more efficiently than poly(lactic-co-glycolic acid)/hydroxyapatite alone. Our data demonstrates that poly(lactic-co-glycolic acid)/hydroxyapatite/simvastatin has the potential to aid in healing bone defects and promoting bone regeneration in the future although we still need to optimize this complex to efficiently promote bone regeneration.

The discrimination of ferrous and ferric states in the human body is one of the basic issues for disease control and prevention because Fe(II) and Fe(III) are a crucial redox pair during the process of material and energy metabolism. Herein, aqueous CdTe quantum dots (QDs) with diversified surface functionalities are applied to discriminate between heme (Fe(II)) and hemin (Fe(III)) by virtue of their difference in quenching QD fluorescence. In aqueous media, the interaction between QDs and heme/hemin mainly involves electrostatic interaction, which is greatly determined by the surface functionalities of the QDs. Thus, by combining the different fluorescence quenching behavior of carboxyl- and/or hydroxyl-functionalized QDs, heme and hemin are discriminated between. In comparison to the discrimination using QDs with single surface functionality, the current method has improved reliability and accuracy.

We report a ligand decoration strategy to enlarge the lattice dilation of quantum dots (QDs), which greatly enhances the characteristic sensitivity of a QD-based thermometer. Upon a multiple covalent linkage of macrocyclic compounds with QDs, for example, thiolated cyclodextrin (CD) and CdTe, the conformation-related torsional force of CD is conducted to the inner lattice of CdTe under altered temperature. The combination of the lattice expansion/contraction of CdTe and the stress from CD conformation change greatly enhances the shifts of both UV-vis absorption and photoluminescence (PL) spectra, thus improving the temperature sensitivity. As an example, β-CD-decorated CdTe QDs exhibit the 0.28 nm shift of the spectra per degree centigrade (0.28 nm/°C), 2.4-fold higher than those of monothiol-ligand-decorated QDs.

High quality CdHgTe quasi core/shell nanocrystals (NCs) were prepared via the one-step method. The relationship between the composition, structure, and property was systematically investigated by the combination of X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission (ICP), and the photoluminescence (PL) measurements. The quantum yield (QY) was ~50% when the feed ratio of Cd(2+) to Hg(2+) was equal to 1. The PL property was further polished, and the QY was improved to ~80% through the variance of the prepared conditions such as the ratio of ligand to metal ion and HTe(-) to metal ion, pH value, and temperature. In addition, the cytotoxic effects of CdHgTe NCs were systematically studied. The results showed that, for Cd0.21Hg0.79Te NCs, its quasi core/shell structure was very stable and little cadmium ions were released. As a result, such NCs showed little cytotoxicity and would find applications in tissue imaging or detection.

Creation of nanoparticle (NP) architectures via a self-assembly strategy is the current means to integrate and/or modulate the functionalities of NPs. In this paper, we demonstrate the capability for constructing NP spherical superstructures through the specific interaction between host and guest molecules, for instance the model system of α-cyclodextrin (α-CD) and oleic acid (OA), which are decorated on two different NPs beforehand. Subsequently, the OA-decorated hydrophobic NPs are dispersed in hexane, whereas the α-CD-decorated NPs are dispersed in water. The blending of these two immiscible solutions produces NP binary superstructures because of the multiple linkages between the α-CD- and OA-decorated NPs. Control experiments indicate that the self-assembly of NPs occurs either at the hexane/water interface to form hybrid films or in the aqueous phase to generate spherical architectures, which strongly depends on the amount and the size of α-CD-decorated NPs. The high ratio and small size of the α-CD-decorated NPs facilitate the formation of spherical architectures. Competitive experiments with the addition of host α-CD and guest sodium oleate clearly confirm that the main driving force for the NP co-assembly is the specific interaction between α-CD and OA. In addition, the flexible decoration of α-CD and OA on the NPs makes the current strategy generally applicable for a variety of NPs, such as the superstructures of Au/Fe(3)O(4), Pt/Fe(3)O(4), and Au/NaYF(4):Yb,Tm, which is expected to promote the further application of NPs in environmental and biological sciences.

A novel microsensor to Hg(2+) was fabricated through self-assembly of aqueous CdTe nanoparticles (NPs). The morphologies of self-assembly mainly included classical dendrites, straight dendrites, and small islands. The formation process of these morphologies was systematically investigated by using the field emission scanning electron microscope, confocal laser scanning microscope, and atom force microscope instruments, etc. The proposed mechanism showed that the dendrite structure was formed via manipulating the short-range van der Waals interaction and long-range electrostatic interaction, which was realized through altering the ligand and concentration of the CdTe NPs. Furthermore, polymers with positive charges were used to effectively control the morphology of the self-assembly as well as improve the property of photoluminescence. These CdTe dendrites were used as microsensors to Hg(2+), which presented the advantages of low cost, quick detection time, high selectivity, and easy operation.

In the conventional procedure of the preparation of aqueous semiconductor nanocrystals (NCs), the growth of NCs was mainly through the thermodynamics-favored Ostwald ripening process. It required additional energy to promote NC growth, such as reflux, hydrothermal method, microwave irradiation, and sonochemical synthesis. Energy-promoted growth usually led to the decomposition of mercapto-ligands and therewith decreased the quality of NCs. Consequently, in this study, the growth of aqueous semiconductor NCs was designed through an amine-promoted kinetic process, which efficiently shortened the growth duration and avoided the decomposition of ligands, thus providing a universal method for preparing various aqueous binary and ternary NCs.

CdTe nanoparticle (NP)/poly(vinylcarbazole) (PVK) functional composite (composite 1) was synthesized via in-situ method. The composite was characterized by using Fourier transformed infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-vis), photoluminescence (PL), and transmission electron microscopy (TEM) instruments. The PL properties of composite 1 were compared with CdTe NP/carbazole containing polymer composites (composite 2 and composite 3) which were prepared through the electrostatic interaction between preformed NPs and carbazole-containing polymers. The efficient electron transfer (ET) made composite 1 possess the lowest PL quantum yield (QY), the part ET made composite 2 applicable in white-light illumination, and the Förster resonant energy transfer (FRET) made composite 3 possess the highest QY. The large difference in their PL properties was mainly resulted from the distance and the nature of interaction between NPs and polymers. These experimental results indicated that the composites with different function could be obtained just by varying the method of preparation.

In order to prepare the building blocks with middle refractive index for fabricating colloidal crystals, a new strategy of cationic ligand protection (CLP) was developed for one-pot preparation of narrow-dispersed CdS spheres with tunable sizes (94-303 nm) and good aqueous dispersibility. The key of CLP strategy is controlling the aggregation behavior of small CdS nanocrystals (NCs) via automatic control of the ligand modification condition at different reaction stages, which is realized by selecting gradual decomposition of thioacetamide (TAA) as the anionic precursor and cetyltrimethylammonium bromide (CTAB) cations as the ligands for anions. Accordingly, at the initial stage of the reaction when TAA decomposes incompletely, the surface atoms of the CdS NCs are mainly Cd cations, leaving less anionic sites for the coordination of ligands. The poor ligand modification condition of CdS NCs still leads to their aggregation. Along with the decomposition of TAA, S anions and cationic ligands gradually dominate the surface of CdS aggregates, providing the aggregates sufficient protection, and thus, they are stably dispersed in water. The current CLP strategy simultaneously involves the processes of NC formation and NC assembly and therefore promotes the one-pot preparation of NC aggregates. The as-prepared CdS spheres possess uniform size, good water-dispersibility, and relative higher refractive index and thus can be applied for fabricating colloidal crystals.

We report a two-step phase transfer approach to locate surfactant bilayers on water-soluble luminescent nanocrystals (NCs), through which the surface functionality of the NCs is tunable. Since the species of both inner and outer surfactants of the bilayer are alterable in wide range, the current effort provides a facile approach to anchor various functional groups on aqueous NCs. The primary results indicate that these bilayer-modified NCs are able to be incorporated with various organic and inorganic materials.

In this study, we demonstrate a new insight into the growth stage of aqueous semiconductor nanocrystals (NCs); namely, that the experimental variable-dependent growth rate and photoluminescence quantum yields (PLQYs) are understandable according to electrostatics. In this context, the aqueous NCs possess (from core outwards) an inorganic core, ligand layer, adsorbed layer, and a diffuse layer. The presence of an electric double-layer not only makes the NCs dispersible in the colloidal solution, but also governs the migration of monomers and monomer adsorption on the NC surface. To maintain NC growth, monomers need to migrate through the double-layer. Consequently, the nature of the diffuse layer influences the ability of monomer diffusion and hence the growth rate of NCs. Systematic studies reveal that the experimental variables, including precursor concentrations, pH of the solution, additional NaCl concentrations, ratio of Cd to ligand, and the nature of the ligands significantly govern the nature of the NC electric double-layer. The experimental variables, which reduce the thickness of the diffuse layer, benefit from monomer diffusion and a rapid growth of NCs. However, on the other hand, the diffuse layer also presents a charge-selective transfer of Cd monomers. The neutral monomers, such as the complex of Cd(2+) and 3-mercaptopropionic acid (MPA) with 1:1 molar ratio [Cd(MPA)], migrate through the diffuse layer more easily than the charged ones [Cd(MPA)(2) (2-) or Cd(MPA)(3) (4-)], thus facilitating the growth of NCs. The nature of the adsorbed layer inside the diffuse layer, defined as the assumed interface of solid NCs and the liquid environment, also affects the growth rate and especially the PLQYs of NCs through the adsorption and coalescence of monomers on this interface. Strong interaction between the adsorbed layer and Cd monomers provides the opportunity to accelerate NC growth and to obtain NCs with high PLQYs.