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Designing and developing photosensitizers with cell membrane specificity is crucial for achieving effective multimodal therapy of tumors compared to other organelles. Here, we designed and screened a photosensitizer CM34 through donor/receptor regulation strategies, and it is able to achieve long‐retention cell membrane targeting. It is not only an extremely excellent cell membrane targeted tumor theranostic agent, but also found to be a promising potential immune activator. Specifically, CM34 with a larger intramolecular twist angle is more likely to form larger aggregates in aqueous solutions, and the introduction of cyanide group also enhances its interaction with cell membranes, which were key factors hindering molecular penetration of the cell membrane and prolonging its residence time on the cell membrane, providing conditions for further membrane targeted photodynamic therapy. Furthermore, the efflux of contents caused by cell necrosis directly activates the immune response. In summary, this study realizes to clarify and refine all potential mechanisms of action through density functional theory calculations, photophysical property measurements, and cellular level mechanism exploration, providing a new direction for the clinical development of cell membrane targeted anti‐tumor immune activators. [ABSTRACT FROM AUTHOR]

Severe aggregation-caused quenching and the lack of special organelle targeting in conventional photosensitizers (PSs) have limited their advantages in terms of their accurate spatial–temporal control and noninvasive features. Furthermore, severe tumor hypoxia equally diminished the effectiveness of treatment. Herein, a series of aggregation-induced emission (AIE) PSs with precise targeting of organelles are synthesized by simply regulating the molecular structure. The rotation of the donor in the molecule was optimized by altering the tail chain of the triphenylamine derivative, which inhibited nonradiative internal conversion and promoted intersystem crossing to facilitate the free radical generation, and the production efficiency of the type I reactive oxygen species exceeds that of the commercial indicator rose bengal (3-fold). The optimal AIE PS named BETTP can specifically target mitochondria and recognize cancer cells. Simultaneously, live/dead cell costaining assays and flow cytometry validated that BETTP nanoparticles (NPs) have the ability to efficaciously ablate cancer cells in hypoxic conditions after encapsulating BETTP into carriers as nanoparticles. In addition, BETTP NPs also manifest superior performance during near-infrared imaging-guided type I photodynamic therapy in solid tumors. Such BETTP NPs demonstrate the critical feasibility of achieving precise delivery of drugs and targeting of organelles for precise therapy in hypoxic environments, providing a reliable reference for tumor hypoxia challenges. [ABSTRACT FROM AUTHOR]

Quasi‐2D perovskites show great promise for light‐emitting diodes owing to suppressed non‐radiative losses enabled by the energy funneling/cascading nanostructures. However, for red emission quasi‐2D perovskites, these ideal energy landscapes for efficient perovskite light‐emitting diodes (PeLEDs) can rarely be achieved due to detrimental aggregation of the low‐dimensional ligands in perovskite precursors, leading to poor device efficiency and stability. Here, a ligand‐modulated dimensionality control strategy is explored to achieve uniform phase distribution and reduce defect density for efficient light emission. In contrast to the model phenethylammonium iodide 2D ligand, the formation of small‐n phases can be inhibited by a structurally similar phenoxyethylammonium iodide ligand owing to the weakened aromatic stacking between ligands. Besides, the oxygen atoms can interact with the uncoordinated Pb2+ ions and promote the NI coordination in the perovskites, which greatly reduces the non‐radiative recombination defects in the ionic lattice. With this simple and effective approach, deep‐red quasi‐2D PeLEDs with record‐high external quantum efficiency of 21.6% and decent operational stability are achieved without the need for additional additives. These results highlight the potential of ligand‐modulated dimensionality control to achieve highly efficient and stable PeLEDs with a facile fabrication process. [ABSTRACT FROM AUTHOR]

Novel organic semiconductor composite thin film doped with 40% and 50% dibenzo[b,d]thiophene-2-yl(4-(3,6-di-tert-butyl-9H-carbozl-9-yl)phenyl) (DBT-BZ-tBuCz) in (4,4′-di(9H-carbazol-9-yl)-1,1′-biphenyl) (CBP) and methanone solution was prepared in dichloromethane (DCM) using the spin-coating process. The band energy recorded for DBT-BZ-tBuCz solutions was 3.79 eV which is less than the electron affinity of n-Si (4.03 eV). This lower band energy proved the advantage of the combined CBP and DBT-BZ-tBuCz:DCM system. The CBP and DBT-BZ-tBuCz:DCM thin film was also coated with poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/Si to form an organic/C–Si/organic structure. It was observed that the open-circuit voltage and the fill factor of the solar cell device improved significantly with coating; a relative increase of 75% power conversion efficiency was noted. Further, the results indicated that the increase in high power conversion efficiency value is attributable to the reduction of recombinative and resistive losses at the rear side of the device, which contributed to the efficient electron-selective CBP in combination with DBT-BZ-tBuCz:DCM contact. Furthermore, the developed solar cell device is economical, inexpensive, and efficient. It has been concluded that these thin films can be used as selective electronic contacts to customize the energy band structure in currently dopant-free silicon (Si) heterojunction solar cells. [ABSTRACT FROM AUTHOR]

The multiple thermal decomposition channels of glycerol are calculated at the M06-2X-D3/6-311+G(d,p) level. In addition, the CAM-B3LYP and ωB97X-D functionals are used to show the functional influence on the free energy barrier. For the highly competitive primary channels, the DLPNO-CCSD(T)/CBS method is applied for the energy calculations. The results show that the dominant paths are: (1) breakage of the C–C, C–O, and O–H bonds of glycerol successively to form carbonyl and alkene, and then generation of water, formaldehyde, and acetaldehyde; (2) glycerol undergoing an intramolecular dehydration reaction and producing 3-hydroxypropionaldehyde; it has two subsequent reactions: C–C bond fracture occurring to form formaldehyde, acetaldehyde, and water; and intramolecular dehydration forming acrolein and water. The ΔG1 is 65.6 kcal mol−1 while the ΔG2 is 65.5 kcal mol−1 at 101 kPa and 298 K, and fitted rate equations are 1.09 × 1013 exp[65.6 × 103/RT] s−1 and 8.07 × 1012 exp[65.4 × 103/RT] s−1, respectively. Besides, UPLC and TG-GC/MS are applied complementarily to investigate the anaerobic pyrolysis products of glycerol at different temperatures. The experimental results are consistent with theoretical calculations. [ABSTRACT FROM AUTHOR]

Pinhole-free perovskite films with low defect density are essential to boost the efficiency of metal halide perovskite light-emitting diodes (PeLEDs). In this work, a novel amphiphilic silicone copolymer (Si14-PEG14-QAC) is introduced into perovskite as a passivation agent to improve the performance of PeLEDs. Si14-PEG14-QAC possesses polyethylene glycol and –NCH3 units, which can interact with perovskite by hydrogen bonding, resulting in high-quality perovskite films with small-size crystals, high coverage, low defect density, and enhanced photoluminescence quantum yield. Consequently, the perovskite films with Si14-PEG14-QAC enable efficient green PeLEDs with an external quantum efficiency of 4.5%, which is much higher than that of the control device without the polymer passivator (0.86%). This work suggests the great potential of silicone copolymers as passivation agents for high-quality perovskite films with high performance. [ABSTRACT FROM AUTHOR]

Endowing thermally activated delayed fluorescence (TADF) emitters with aggregation-induced emission (AIE) characteristics and a fine film-forming ability is significant for realizing efficient solution-processed non-doped organic light-emitting diodes (OLEDs). Herein, a class of AIE-active TADF emitters adopting phenyl ketone as an acceptor and 9,9-diphenyl-9,10-dihydroacridine (or 9,9-dimethyl-9,10-dihydroacridine and phenoxazine) as a donor are exploited. The suppressed intermolecular packing derived from the highly twisted molecular configuration and multiple transition channels induce improved luminescence efficiency and more efficient reverse intersystem crossing (RISC) simultaneously in the solid state. Solution-processed non-doped and doped devices with the maximum external quantum efficiencies (EQEs) of 12.1% and 17.6%, respectively, are obtained when employing the dendritic luminogens of 3PXZ-BPCTPA as the emitter, which are better than the reference non-dendritic luminogens of PXZ-BPCTPA. This work thus provides an approach for designing dendritic luminogens with TADF and AIE features as promising candidates for high-performance solution-processed OLEDs. [ABSTRACT FROM AUTHOR]

A new series of thermally initiated self-crosslinkable diarylfluorene-based copolymers have been reasonably designed and successfully synthesized, aiming to improve both efficiency and stability of blue light-emitting diodes. The crosslinking groups in side chains endow these copolymers with excellent solvent resistance and anti-oxidation abilities, as verified through Raman and UV-vis absorption as well as variable temperature photoluminescence spectra. The surface roughness of the thermal self-crosslinking copolymer film is almost unchanged with a low value of 0.73 nm, compared to a roughness of 0.68 nm for the original film without crosslinking. The modulation of the energy levels of copolymers with/without a crosslinking reaction is analyzed through computations and experiments. The up-shifted highest occupied molecular orbital (HOMO) energy level of the thermal self-crosslinking copolymer film by about 0.1 eV in comparison with that of the uncrosslinked copolymer film is conducive to the establishment of a better pathway for hole injection from the anode. In the end, a high external quantum efficiency of 4.29% with a maximum brightness of 7491 cd m−2 is achieved for the optimized blue polymer light-emitting diode (PLED) with the use of a thermal crosslinking copolymer emitter, which is the highest efficiency reported so far in the field of self-crosslinking blue fluorescent emitters. This work demonstrates that the introduction of self-crosslinkable side-chain units far from the blue polymer backbone is a very promising strategy for developing highly efficient and stable blue PLEDs. [ABSTRACT FROM AUTHOR]

Real-time monitoring of the cytochrome P450 1A1 (CYP1A1) activity in complex biological systems via a practical tool is highly sought after because of its significant role in the metabolism and bioactivation of various xenobiotics. Herein, according to slight differences in the 3D structure and substrate preference between CYP1A1 and its homologous CYP1A2, a series of novel ratiometric fluorescent probes were designed and synthesized using 1,8-naphthalimide because of its trait of naked-eye visualization and ratiometric fluorescence to achieve the detection of CYP1A1 in biological samples. Among these probes, NEiPN showed good water solubility, highly isoform selectivity and great sensitivity (LOD = 0.04874 nM) for CYP1A1 under simulated physiological conditions, which makes it favorable for monitoring CYP1A1 in vivo. Remarkably, NEiPN exhibited excellent reproducibility when it was used to detect the CYP1A1 content in human liver microsomes, which indicated that it has a great potential for quantifying the CYP1A1 content in real biological samples. Furthermore, NEiPN showed relatively low cytotoxicity and has been successfully applied in biological imaging in living cells and zebrafish. These findings indicate that NEiPN is capable of real-time monitoring of the activity of endogenous CYP1A1, which could provide support for CYP1A1-associated pathological processes. [ABSTRACT FROM AUTHOR]

The development of luminescent materials simultaneously possessing thermally activated delayed fluorescence (TADF), aggregation-induced emission (AIE), and high luminescence efficiency in the solid state is urgent for fabricating efficient non-doped organic light-emitting diodes (OLEDs). Herein, two novel emitters bearing triphenylamine as the donor moiety and phenyl ketone as the acceptor unit, named as DTPA-DTM and DTPA-DDTM, were designed and synthesized. Combined charge transfer pathways in a single molecule could be achieved via linking the donor and acceptor units in the ortho-position, which was favorable for reducing singlet–triplet energy splitting (ΔEst) and increased the luminescence efficiency. The TADF characteristics, AIE properties, solvatochromism, theoretical calculations, and crystallography of the designed emitters were systematically investigated to determine the structure–property relationship. By virtue of the inhibited concentration quenching in the solid state, the non-doped OLEDs employing DTPA-DDTM as the emitter realized high current efficiency (LE) and external quantum efficiency (EQE) of 25.6 cd A−1 and 8.2%, respectively. The obtained results clearly demonstrate that combining the charge transfer pathways in a single molecule is a promising strategy to construct highly efficient TADF emitters that can be used for fabricating non-doped organic light-emitting diodes. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymers with cationic hydrophilic moieties and different ratios of hydrophobic portion to hydrophilic portion were designed and synthesized via the combination of hydrosilylation reactions and quaternization reactions. The structures were characterized through Fourier transform infrared spectroscopy, 1H NMR, 13C NMR and gel permeation chromatography. The measurements of critical micelle concentrations, electrical conductivities and zeta potentials indicated that the copolymers could self-assemble into nanoparticles with charges around the surface in aqueous solution. The sizes of the micelles were between 67 nm and 104 nm detected by dynamic light scattering. The self-assembled micelles were used as drug carriers to encapsulate a model drug (tocopherol), and their drug-loading content ( DLC) and efficiency ( DLE) were determined by UV−visible spectra, resulting in considerable drug-loading capacity to a tocopherol maximum up to 17.2% ( DLC) and 80.3% ( DLE) with a size of 90 nm. The blank micelles and drug-loaded micelles displayed a spherical shape detected by transmission electron microscopy, which demonstrated not only the self-assembly behaviors but also the drug-loading performances of the cationic amphiphilic copolymers. All the results demonstrated that the cationic amphiphilic copolymers could be used as potential electric-responsive drug carriers. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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Kinetics of the cationic ring opening polymerization of octamethylcyclotetrasiloxane (D) in bulk initiated by solid superacid was studied. The optimalizing experimental conditions were based on preliminary experiments. Higher temperature was beneficial to equilibrium conversion while stirring intensity beyond a certain level displayed no obvious effect on the rate of the reaction. A kinetic model was elicited and kinetic parameters were obtained through optimization. The calculated activation energies were 32.6 and 34.1 kJ mol for D4 and all other annuluses (D), respectively. [ABSTRACT FROM AUTHOR]

A selective Hg/Cu-induced OFF-ON-OFF type of signaling pattern was calculated by density functional theory and time-dependent density functional theory method. Geometries, molecular orbitals, and interaction thermal energies were evaluated at the restricted hybrid Becke's three-parameter exchange functional using 6-31+G(d) basis set and relativistic effective core potentials. The optimized geometric structures are used to perform natural bond orbital (NBO) analysis. The main type of driving force is the electrostatic interactions between the metal ions and the electron-donating oxygen and nitrogen atoms. Maximum absorption spectrums of the complexes are mainly contributed by the HOMO → LOMO transition. The high selectivity of ligand HNB for Hg results in a 'turn-on' fluorescent phenomenon. [ABSTRACT FROM AUTHOR]

The fabrication of electroluminescent devices that combine high device performance with simple device configuration remains an attractive challenge due to their low cost and simple fabrication processes. In this paper, a new series of electrophosphorescent small molecule iridium(iii) complexes with diphenylamine-based dendrons of good solubility have been designed. The relationships between their dendritic structures and their photophysical, electrochemical, and electrophosphorescent performances have been systematically investigated. With second-generation dendrons, the photoluminescence quantum yields of the neat film of the dendrimers are almost seven times higher than that of their prototype G0 (Ir(LG0)3, LG0 = 1-methyl-2-phenyl-1H-benzimidazole), and three times that of the first-generation dendron G1 (Ir(LG1)3, LG1 = 4-(1-methyl-1H-benzimidazol-2-yl)-N,N-diphenylbenzenamine). High-quality films of the dendrimers G2 (Ir(LG2)3, LG2 = 1-methyl-2-[4-bis[4-(diphenylamino)phenyl]-aminophenyl]-1H-benzimidazole) and G2Cz (Ir(LG2Cz)3, LG2Cz = 1-methyl-2-[4-bis[4-(9-carbazolyl)phenyl]-aminophenyl]-1H-benzimidazole) have been fabricated by spin-coating, producing highly efficient, non-doped phosphorescent organic light-emitting diodes (PhOLEDs). With a device structure of indium tin oxide/poly(3,4-ethylene-dioxythiophene):poly(styrene sulfonic acid)/neat dendrimer/Cs2CO3/Al, maximum luminous efficiencies of 14.02 cd A−1 and 18.35 cd A−1 have been realized, exhibiting ultrahigh luminous efficiency for single-layer self-host green PhOLEDs. The excellent performances are due to the flower bouquet-shaped iridium dendrimers, which may improve the electron injection and result in greater balance between electron and hole fluxes by the exposure of electron-deficient moieties. The molecular design reported here provides a simple and effective approach to balance charge injection/transporting capacities and develops highly efficient non-doped phosphors suitable for low-cost single-layer device technologies. [ABSTRACT FROM AUTHOR]

The fabrication of electroluminescent devices that combine high device performance with simple device configuration remains an attractive challenge due to their low cost and simple fabrication processes. In this paper, a new series of electrophosphorescent small molecule iridium(iii) complexes with diphenylamine-based dendrons of good solubility have been designed. The relationships between their dendritic structures and their photophysical, electrochemical, and electrophosphorescent performances have been systematically investigated. With second-generation dendrons, the photoluminescence quantum yields of the neat film of the dendrimers are almost seven times higher than that of their prototype G0 (Ir(LG0)3, LG0 = 1-methyl-2-phenyl-1H-benzimidazole), and three times that of the first-generation dendron G1 (Ir(LG1)3, LG1 = 4-(1-methyl-1H-benzimidazol-2-yl)-N,N-diphenylbenzenamine). High-quality films of the dendrimers G2 (Ir(LG2)3, LG2 = 1-methyl-2-[4-bis[4-(diphenylamino)phenyl]-aminophenyl]-1H-benzimidazole) and G2Cz (Ir(LG2Cz)3, LG2Cz = 1-methyl-2-[4-bis[4-(9-carbazolyl)phenyl]-aminophenyl]-1H-benzimidazole) have been fabricated by spin-coating, producing highly efficient, non-doped phosphorescent organic light-emitting diodes (PhOLEDs). With a device structure of indium tin oxide/poly(3,4-ethylene-dioxythiophene):poly(styrene sulfonic acid)/neat dendrimer/Cs2CO3/Al, maximum luminous efficiencies of 14.02 cd A−1 and 18.35 cd A−1 have been realized, exhibiting ultrahigh luminous efficiency for single-layer self-host green PhOLEDs. The excellent performances are due to the flower bouquet-shaped iridium dendrimers, which may improve the electron injection and result in greater balance between electron and hole fluxes by the exposure of electron-deficient moieties. The molecular design reported here provides a simple and effective approach to balance charge injection/transporting capacities and develops highly efficient non-doped phosphors suitable for low-cost single-layer device technologies. [ABSTRACT FROM AUTHOR]