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In this paper, two D–π–A structured self-assembly monolayers (SAMs: FNE29 and DT-1) are self-assembled onto the indium tin oxide (ITO) substrates as hole-transport layers (HTLs) for inverted perovskite solar cells (PSCs). Due to the presence of a terminal –COOH group, the SAMs can be adsorbed onto the surface of the ITO substrate through the covalent self-assembly. The employed FNE29 and DT-1 SAMs differ in the π bridge (linker); the FNE29 SAM has a hexyl-substituent terthiophene while the DT-1 SAM contains dithienopyrrolobenzotriazole as the linkers, respectively. Upon the self-assembly of ITO with the SAMs, the power conversion efficiency (PCE) is enhanced from 9.36% for the control device to 16.75% for the FNE29 modified device and further to 20.65% for the DT-1 modified PSCs. As the D–π–A structured SAMs with a large fused π bridge as a linker is beneficial for hole transfer, the self-assembly of DT-1 achieves a higher PCE with an improved fill factor. Moreover, due to the good hydrophobic characteristics of the SAMs, the inverted PSC devices self-assembled with these two molecules display good stability, maintaining over 80% of the original PCE after storage in air (relative humidity of 20–30%) for ∼1000 h without encapsulation. In addition, the FNE29 and DT-1 based devices also show good photostability after operating for 1000 h. These results indicate that the D–π–A structured SAMs with large conjugated fused π bridges as linkers have obvious advantages as the HTLs for inverted PSCs. [ABSTRACT FROM AUTHOR]

Cancer as a leading cause of premature death worldwide has become a major threat to human health due to the high incidence and mortality. Monitoring tumor markers are reliable and significantly important for early detection of cancers. In complex biological systems, it is of great urgency but still remains challenging to conceive a fluorescent probe with multiple tumor markers detection property. Hydrogen sulfide (H 2 S) and pH are two target biomarkers for diagnosis of early cancer. The preparation of a novel probe with H 2 S and pH dual detection functions is highly anticipated. Herein, a novel sequential detection probe HTPQ-HS for H 2 S and pH has been developed. In this system, HPQ (2-(2 -hydroxyphenyl)-4(3H)-quinazolinone) structure combined with triphenylamine is applied as the fluorophore, and 2, 4-dinitrophenylsulfonyl group is used as the recognition group. In the presence of H 2 S, HTPQ-HS is transformed into product HTPQ-OH which shows fluorescence enhancement (29-fold) at 525 nm in less than 4 min and further displays repeatable acid-base responsive ability. HTPQ-HS is able to sequentially response to H 2 S and pH in living cells and does not react directly with pH. Owing to the low cytotoxicity, HTPQ-HS is able to detect exogenous and endogenous H 2 S in colon cancer cells and mice, monitor H 2 S in inflammation model and in foodstuffs. As the environment changes from acidic to alkaline, the fluorescence intensity ratio (I 470 /I 530) of product HTPQ-OH changes remarkably, illustrating the ratiometric fluorescent responsiveness to pH. A multifunctional fluorescent probe HTPQ-HS for sequential detection of H 2 S and pH is synthesized. Probe HTPQ-OH realizes the monitoring of dynamic changes in intracellular pH and displays prospective application in security printing. We expect that our work could offer an important guidance on the development of multifunctional fluorescent probes for visualizing H 2 S and pH in biology and environment. [Display omitted] • A Multifunctional fluorescent probe for sequential detection of H 2 S and pH is designed. • HTPQ-HS can detect exogenous and endogenous H 2 S in colon cancer cells and mice. • H 2 S-responsive HTPQ-HS test strips can be used to detect the freshness of food. • HTPQ-OH is able to realize the monitoring of dynamic changes in intracellular pH. • HTPQ-OH displays excellent security printing application and fluorescence stability. [ABSTRACT FROM AUTHOR]

Abstract Two efficient dye-sensitized solar cells have been fabricated by two novel D–D–π–A phenothiazine-based organic dyes (PH2 and PH3) with an encapsulated insulated molecular wire (EIMW) as an auxiliary donor. The cell sensitized by PH2 with EIMW as an auxiliary donor shows a much higher photovoltage (V oc) relative to the reference dye PH1 without EIMW, because the former dye can inhibit dye aggregation and suppress the charge recombination effectively. The results show that the cell sensitized by PH2 with co-adsorption of chenodeoxycholic acid obtains a high power conversion efficiency, even higher than that of the cell based on N719. Thus, an effective way to increase the photovoltage and efficiency of the DSSCs has been developed by introducing the EIMW into the organic dyes due to the effective inhibition of dye aggregation and charge recombination. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A facile one-pot synthesis method was reported. • Non-fluorinated superhydrophobic latex composite materials were fabricated. • Remarkable mechanochemical robustness and multifunctionality were obtained. • The water repellency of materials was remained after suffering serious disruption. • The samples are easily recoverable after contamination. Abstract Superhydrophobic materials have attracted immense commercial and academic interests in recent years. However, the poor mechanical durability has restricted their practical applications where high durability is required. Here, a facile one-pot synthesis method was reported to fabricate multifunctional superhydrophobic composite materials with remarkable mechanochemical robustness, stain repellency, oil-water separation and sound-absorption. Their mechanical and chemical durability could be greatly improved by chemically adhering epoxy resin microspheres (ERMs) on 3-D porous skeleton structures of latex sponge. The materials could retain superhydrophobicity after going through sandpaper abrasion, ultrasonication, multiple knife scratch, tape peeling and finger wiping, and exposure to UV irradiation and high temperature. The materials are able to maintain the repellency against strong acid and alkali droplets. The combined excellent mechanical properties, liquid repellency & selectivity, and other functional properties displayed by this type of material have made it a strong candidate for a range of industrial applications. [ABSTRACT FROM AUTHOR]

Three novel metal-free organic dyes IT , IPT and IQT , containing a dipentyldithieno[3,2- f :2′,3′- h ]quinoxaline ( DPQ ) unit as the π-bridge were synthesized and the impacts of the auxiliary acceptors on the photovoltaic performances were studied. IQT with 2,3-dipentylquinoxaline as the auxiliary acceptor exhibited the highest efficiency of 7.98%, with a short-circuit photocurrent density of 16.87 mA cm −2 , an open-circuit photovoltage of 0.71 V, and a fill factor of 0.67, under standard global AM 1.5G solar light condition. IPT with the strongest electron-withdrawing group (2,3-dipentylpyridopyrazine) as the auxiliary acceptor could red-shift the absorption range, but showed the weakest performance, which might be due to the electron trap of the 2,3-dipentylpyridopyrazine unit. The results show that incorporating auxiliary acceptor with moderate electron-deficient ability can extend the absorption range and adjust the molecular orbital energy levels, improving the photovoltaic performance. [ABSTRACT FROM AUTHOR]

Three novel quinoxaline-based donor-π-acceptor type organic dyes were synthesized and explored as sensitizers in dye-sensitized solar cells (DSSCs). The impacts of various π-conjugation configurations which contain different quinoxaline derivatives on the absorption properties, electrochemical properties and photovoltaic performances, as well as theoretical calculations have been investigated systematically. The photovoltaic performances of these dyes were found to be highly relevant to the π-conjugated configurations. In particular, the DSSC based on the dye with 2,3-dioctylquinoxaline as the spacer exhibited the highest efficiency of 8.20% with a short-circuit photocurrent density of 17.83 mA cm −2 , an open-circuit photovoltage of 0.71 V, and a fill factor of 0.65, under standard global AM 1.5G solar light condition. However, the DSSC based on the dye with a more conjugated dithieno [2,3- a :3′,2′- c ]phenazine core as the spacer exhibited a lower efficiency due to serious intermolecular aggregation. When the intermolecular aggregation is inhibited, the efficiency can be improved greatly. The results confirm that the configuration of the π-conjugation of the dyes should be considered for the improvement of the photovoltaic performance. [ABSTRACT FROM AUTHOR]

Two novel zinc porphyrin dyes containing either benzotriazole or 2 H -[1,2,3]triazolo[4,5- c ]pyridine as auxiliary acceptors, respectively, were synthesized for dye-sensitized solar cells. These two auxiliary acceptors were firstly applied into porphyrin based dyes. The photophysical and electrochemical properties of the dyes were investigated. These two dyes show the whole visible light absorption when they are adsorbed on the TiO 2 film, which means that they are promising sensitizers for dye-sensitized solar cells. The absorption intensity of the triazolopyridine containing dye is higher than that of the benzotriazole containing dye, resulting in a better light harvesting. Thus, the dye-sensitized solar cell based on the former dye achieved higher conversion efficiency of 6.65% than the cell based on the latter dye (6.17%) with chenodeoxycholic acid as the coadsorbant. [ABSTRACT FROM AUTHOR]

Four novel D–π–A–π–A metal-free organic dyes Q1-Q4 were synthesized and the impacts of the auxiliary acceptors on the photovoltaic performances were studied. Q2 with quinoxaline as the auxiliary acceptor exhibited the best photovoltaic performance due to its highest short-circuit photocurrent density (17.22 mA cm −2 ), leading to a power conversion efficiency of 7.42% under simulated AM 1.5 G illumination. Q1 with the strongest electron withdrawing group (pyrazino[2,3- g ]quinoxaline) as the auxiliary acceptor showed the weakest performance, which can be attributed to electron trap and mismatch of energy-level. The results showed that the different electron-withdrawing property of auxiliary units significantly influenced the absorption, energy levels and photovoltaic performance. Incorporating auxiliary acceptor with moderate electron-deficient ability can extend the absorption range and adjust the molecular orbital energy levels, resulting in better photovoltaic performance. [ABSTRACT FROM AUTHOR]

Four novel organic dyes DT1-DT4 containing a dithienopyrrolobenzotriazole unit were synthesized and applied in dye sensitized solar cells, where dithienopyrrolobenzotriazole moiety was introduced as a π-spacer for the first time. The four dyes exhibited good light harvesting efficiency with high molar extinction coefficients and broad spectral response. The influence of the different electron donor on the photovoltaic performance was evaluated. The effects of the linear and branched alkyl chains in the π-bridge on the photophysical, electrochemical and photovoltaic performance were systemically investigated. The results show that branched alkyl chains are better than linear alkyl chains in inhibition of intermolecular aggregation and electron recombination between the injection electrons and electrolyte. Finally, DT4 sensitized solar cell obtained a power conversion efficiency of 8.05%. These results indicate that the dithienopyrrolobenzotriazole-based organic sensitizer is a promising candidate for efficient dye sensitized solar cells. [ABSTRACT FROM AUTHOR]

Three types of novel diketopyrrolopyrrole-based organic dyes ( Type 1 – 3 ) with phenyl unit as an additional π -bridge and triphenylamine or phenothiazine as the donors are designed and synthesized for dye-sensitized solar cells (DSSCs). Type 1 dyes incorporating the donor segment directly to the diketopyrrolopyrrole core lead to a better electron communication between the donor and acceptor, allowing an efficient charge transfer process. Type 2 and Type 3 dyes with a phenyl unit between the donor and diketopyrrolopyrrole unit show lower delocalization of the excited state. Compared with Type 3 dyes, Type 1 dyes exhibit higher conjugated skeleton co planarity and shorter electron transfer distance from the donor to TiO 2 , resulting in the red-shifts of absorption and promotion of electron injection, respectively. Moreover, the dyes with triphenylamine as the donor display better UV performance and lower trend of aggregation than the dyes with phenothiazine as the donor. Finally, a power conversion efficiency of 8% with chenodeoxycholic acid as the co-absorbant for the DSSC based on Type 1 dyes with triphenylamine is achieved. The results reveal that the donors, the position and number of phenyl unit of the dyes significantly influence the photovoltaic performance of their DSSCs. [ABSTRACT FROM AUTHOR]

Natural soiling of photovoltaic (PV) panel is an increasing problem especially in arid and desert areas. Finding a strategy that can reduce dust adhesion on PV panels is highly desirable but remains challenging. In this paper, different wettability of transparent coatings including superhydrophilic, hydrophilic, hydrophobic and superhydrophobic coatings were prepared to investigate the importance of surface roughness and surface energy. Their anti-soiling effects were investigated under different airflow velocity and different tilt angles. Dust deposition density, reduced transmittance, the ratio of reduced transmittance between bare glass surfaces and coatings, and PV efficiency reduction were used to characterize dust resistance performances. It is found that dust adhesion on superhydrophilic coatings was eminently governed by their respective high surface energy, with surface roughness rendering lesser contribution towards resisting/adhering effects. However, for other three coatings, further reducing the surface energy had little influence on the improvement of dust-proof ability. A large airflow velocity is beneficial to resist dust adhesion for all four types of coatings. However, a large airflow velocity has a limited ability to improve the anti-soiling effect of superhydrophilic coating under different tilt angles compared with other three coatings. The anti-soiling coatings can be referred to hydrophilic and hydrophobic coatings, not limited to superhydrophobic coating only. The study provides an invaluable guiding significance for preparation of dust-resistant coatings. • The anti-soiling effects of different wettability of transparent coatings were investigated. • The anti-soiling effects were investigated under different airflow velocity and tilt angle. • Large airflow velocity was beneficial to resist dust adhesion for all four types of coatings. • The anti-soiling effect of superhydrophilic coating was the weakest under different tilt angles. • Surface roughness and surface energy both rendered contribution towards anti-soiling. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is a pioneering and effective anticancer modality with low adverse effects and high selectivity. Hypochlorous acid or hypochlorite (HClO/ClO−) is a type of inflammatory cytokine. The abnormal increase of ClO− in tumor cells is related to tumor pathogenesis and may be a "friend" for the design and synthesis of responsive phototherapy agents. However, preparing responsive phototherapy agents for all-in-one noninvasive diagnosis and simultaneous in situ therapy in a complex tumor environment is highly desirable but still remains an enormously demanding task. An acceptor-π bridge-donor-π bridge-acceptor (A-π-D-π-A) type photosensitizer TPTPy was designed and synthesized based on the phenothiazine structure which was used as the donor moiety as well as a ClO− responsive group. TPTPy was a multifunctional mitochondria targeted aggregation-induced emission (AIE) photosensitizer which could quickly and sensitively respond to ClO− with fluorescence "turn on" performance (19-fold fluorescence enhancement) and enhanced type I reactive oxygen species (ROS) generation to effectively ablate hypoxic tumor cells. The detection limit of TPTPy to ClO− was calculated to be 185.38 nM. The well-tailored TPTPy anchoring to mitochondria and producing ROS in situ could disrupt mitochondria and promote cell apoptosis. TPTPy was able to image inflammatory cells and tumor cells through ClO− response. In vivo results revealed that TPTPy was successfully utilized for PDT in tumor bearing nude mice and exhibited excellent biological safety for major organs. A win-win integration strategy was proposed to design a tumor intracellular ClO− responsive photosensitizer TPTPy capable of both type I and type II ROS production to achieve photodynamic therapy of tumor. This work sheds light on the win-win integration design by taking full advantage of the characteristics of tumor microenvironment to build up responsive photosensitizer for in situ PDT of tumor. [Display omitted] • An AIE photosensitizer TPTPy for ClO− detection and follow-on PDT is designed. • TPTPy can target mitochondria and generate type I and type II ROS for PDT. • TPTPy can detect ClO− with fluorescence turn on and enhanced type I ROS generation. • TPTPy can detect endogenous ClO− in inflammatory cells and tumor cells. [ABSTRACT FROM AUTHOR]

Two novel organic dyes TLEP-1 and TLEP-2 based on phenothiazine with trilateral π-conjugation extensions were designed and synthesized for dye-sensitized solar cells, where phenothiazine ring was linked with two phenyl moieties at 7- and 10-positions as the first and second π-conjugation extensions, and with furan or thiophene ring at 3-position as the third π-conjugation extension for TLEP-1 and TLEP-2 , respectively. The influence of the π-conjugation extensions on the photovoltaic performance was evaluated. The cell based on TLEP-2 exhibits an impressive short-circuit photocurrent density of 14.87 mA cm −2 , which is much higher than the cell based on the reference dye without π-conjugation extension (9.01 mA cm −2 ), leading to high power conversion efficiency of 7.33% under simulated AM 1.5 G illumination condition. The results indicate that the trilateral π-conjugation extensions are an effective way to improve the photovoltaic performance of the dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

A new di-anchoring organic dye based on phenothiazine featuring A-D-π-D-A (acceptor-donor-π-linker-donor-acceptor) configuration with fluorene as the π linker was designed and successfully synthesized. Compared to the corresponding mono-anchoring D-A congener, this new dye exhibited a broader and stronger absorption in the light wavelength ranging from 400 nm to 600 nm and thus showed a more efficient photovoltaic performance for dye-sensitized solar cells (DSSCs). The overall power conversion efficiency ( η ) of this new dye in a sensitized solar cell amounted to 5.70%, which is 17% higher than that of the equivalent based counterpart (4.87%). On the other hand, the introduction of two thiophene units at position-2 and -7 of the fluorene unit gave another new dye with extended conjugation. This extended conjugation dye showed a higher molar extinction coefficient ( ε ), but exhibited π-stacked aggregation on the TiO 2 surface, resulting in low efficiency of electron injection. The results indicate that the di-anchoring dye with fluorene as π linker is a promising candidate for efficient DSSCs. [ABSTRACT FROM AUTHOR]

Abstract: Three organic dyes with double D–A system were synthesized and applied in the dye-sensitized solar cells. These dyes contain phenothiazine as an electron donor and cyanoacetic acid as an acceptor/anchor. Linkages were incorporated at the ortho-, meta- and para-positions and their impact on the performance of photovoltaic was observed. Among them, the dye with a para-position linkage exhibited the highest short-circuit photocurrent density (12.26 mA cm−2) and open-circuit photovoltage (756 mV), leading to the best overall efficiency (6.14%) due to better light harvesting capacity under standard global 1.5 AM conditions. Under similar measuring conditions the dyes with ortho and meta-position linkage delivered sunlight to electricity conversion efficiencies of 5.25% and 5.85% respectively. The result shows the position isomer of the linkage units influences the photophysical characteristics, dye loading on the film and electron lifetime. [Copyright &y& Elsevier]

• Five new dithienopyrrolobenzothiadiazole-based organic dyes are reported. • DTPBT is used as donor for organic sensitizer for the first time. • W3 with phenothiazine shows better ability of suppressing electron recombination. • W5 sensitized DSSC achieves an efficiency of 7.98%. Five new dithienopyrrolobenzothiadiazole (DTPBT)-based organic sensitizers were prepared for dye-sensitized solar cells (DSSCs). In this work, DTPBT unit was used as a donor to construct mono- and di-anchored metal-free organic sensitizers for the first time. The DTPBT unit applied as a donor or a π-spacer in mono-anchored dyes (W1 and W2) greatly influences the absorption range, HOMO-LUMO energy level and the solar cell performance of the dyes. The results show that the DTPBT unit is more suitable for acting as a π-spacer in D-π-A dyes. Di-anchored dyes exhibit broader photo-spectra response and higher molar extinction coefficients than those of the mono-anchored dyes. Di-anchored dyes W4 and W5 with DTPBT as the donor, thiophene as the π-bridge achieve high power conversion efficiencies of 7.93%, 7.98% with 1 mM CDCA as the co-adsorbent, respectively. The results suggest that the DTPBT moiety is a promising donor candidate to develop efficient double anchored organic dyes for DSSCs. [ABSTRACT FROM AUTHOR]

Fluorescence imaging-guided photodynamic therapy (PDT) is considered as an ideal alternative strategy to treat tumors. However, insufficient supply of oxygen in solid tumor tissue, aggregation-caused quenching (ACQ) of photosensitizers (PSs), poor targeting-specificity of cancer cells and short wavelengths of emission are representative obstacles for effective PDT. In this paper, three D-π-A structured PSs TSB-OH , TSBPy-OH , TSBPy-DNT with aggregation induced emission (AIE) properties and integrated type I and type II ROS generation were synthesized by modulating distinct acceptor units. Among them, TSBPy-OH is optimal with multiple advantages including near-infrared emission, good biocompatibility, remarkably intracellular ROS production ability, mitochondria targeting capability inducing cell apoptosis and enhancing PDT, and long-term tumor retention ability for imaging-guided photodynamic therapy. More importantly, efficient in vitro cancer cells damage, in vivo tumor ablation and ignorable damage in major organs during PDT are demonstrated, suggesting potential capability of TSBPy-OH in safe and effective fluorescence imaging-guided PDT. This successful example of AIE theranostics design would provide a reference for the modification of D-π-A structure organic AIEgens. [Display omitted] • Three organic photosensitizers with AIE characteristic were developed. • TSBPy-OH exhibited excellent type Ⅰ and type Ⅱ ROS generation ability. • TSBPy-OH showed mitochondria targeting capability and could induce cell apoptosis. • TSBPy-OH could effectively inhibit tumor growth and had good biological safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four organic photosensitizers with AIE characteristic were developed. • TSPy-B exhibited excellent ROS (type I and type II) generation ability. • TSPy-B showed biotin receptor and mitochondria dual-targeted capability in cells. • TSPy-B could effectively inhibit tumor growth and had good biological safety. Rational design of organelle targeted therapeutic platform in where the drug can be targeted to destroy tumor cells as much as possible, is one of the effective ways to improve the therapeutic outcomes and minimize the cytotoxicity to normal cells. Here, photosensitizer TSPy-B with aggregation-induced emission (AIE) feature, biotin receptor and mitochondria dual-targeted capability, and high reactive oxygen species (ROS) generation efficiency was designed for fluorescence imaging guided photodynamic therapy (PDT) by linking biotin group to D-π-A type AIE dyes via ester bonds. Notably, cell imaging experiments showed that TSPy-B could selectively target tumor cells with biotin receptor overexpression and further exhibit mitochondria targeting ability. The in vitro anticancer mechanism confirmed that after cell internalization, TSPy-B localized in the mitochondrial site and produced ROS resulting in mitochondrial dysfunction and cell death. ROS generation experiments showed that TSPy-B could simultaneously produce 1O 2 and highly toxic free radicals which not depended on the oxygen level of solid tumor. The cell killing effect of TSPy-B was also confirmed in hypoxic culture model. In vivo photodynamic therapy experiments demonstrated that TSPy-B could effectively inhibit tumor growth and had good biological safety. This work provides a choice for development of highly targeted photosensitizers for clinical fluorescence imaging guided PDT. [ABSTRACT FROM AUTHOR]

Abstract Four novel benzotriazole-based donor-acceptor-donor (D-A-D) type hole transport materials (HTMs) BTA1-2 and DT1-2 are synthesized to investigate the effect of the acceptors on the photovoltaic performance of perovskite solar cells (PSCs). The acceptors include nonfused core (thiophene-benzotriazole-thiophene) and fused core (dithienopyrrolobenzotriazole, DTBT). Systematical investigation reveals that the acceptor greatly influences the absorption, energy level, hole transfer and extraction, and photovoltaic performances of the HTMs. The dopant-free HTMs DT1-2 with DTBT core exhibit better hole transfer and extraction performance, and then obtain better photovoltaic performance than that of BTA1-2. Especially, the PSC using DT2 without any dopants obtains a power conversion efficiency of 13.22%, which is outperforming than that of spiro-OMeTAD (10.41%). When doping with Li-TFSI/TBP (lithium bis(trifluoromethylsulphonyl)imide/tert-butylpyridine), DT2 -based cell achieves an improved efficiency of 15.77%. In addition, the different alkoxyl chain lengths on triphenylamine has a significant impact on the conductivity, hole mobility, hole extraction, and photovoltaic performance. The stability testing of the PSCs shows that the four HTMs based devices display improved stability than spiro-OMeTAD. These results certify that the fused acceptor core DTBT is a promising core for efficient D-A-D type HTMs towards PSCs. Graphical abstract Image 1 Highlights • Novel D-A-D types HTMs with different acceptor cores were reported. • Acceptor core of the HTMs greatly influences the performance of the PSCs. • DT-2 based PSC obtains a power conversion efficiency of 15.77%. • DT1-2 exhibit better conductivity and hole mobility than spiro-OMeTAD. [ABSTRACT FROM AUTHOR]

Abstract A novel colorimetric fluorescent chemosensor TP1 with a D-π-A structure for the detection of (cyanide) CN− has been developed. TP1 is capable of showing high selectivity and sensitivity towards CN− over a wide range of other interfering anions. After reaction with CN−, TP1 shows a significant blue-shift of absorption peak from 514 to 437 nm, which induces color changes from amaranth to yellow. Non-fluorescent TP1 upon interaction with CN− exhibits a ca. 17-fold fluorescence enhancement at 551 nm, resulting in strong orange emission. The sensing mechanism of TP1 recognizes CN− which undergoes a nucleophilic addition reaction. Moreover, the detection limit of the probe TP1 towards CN− is 1.4 × 10−8 M, which is far lower than the WHO guideline of 1.9 μM cyanide for drinking water. In addition, the cell imaging experiments certify that TP1 can be successfully applied as a bioimaging agent for monitoring CN− in pheochromocytoma cell (PC12). Graphical abstract Image 1 Highlights • Probe TP1 with D-π-A featured structure for CN− was developed. • TP1 can detect cyanide with high sensitivity and selectivity. • The detection limit of TP1 towards CN− was 1.4 × 10−8 M. • TP1 can be applied in cell imaging with turn-on emission and low cytotoxicity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A NIR-II photothermal agent TPTQ with AIE characteristic was developed. • TPTQ NPs showed high photothermal conversion efficiency of 73.32%. • Acceptor/π-bridge planarization and donor rotation design strategies were applied. • TPTQ NPs had photothermal antitumor effect and real-time visualization ability. Aggregation-induced emission luminogens (AIEgens) with second near infrared (NIR-II) fluorescence and photothermal therapy (PTT) have recently attracted great research interest. The formidable challenge, the competing balance between radiation-mediated NIR-II fluorescence imaging and non-radiation NIR-PTT, prevents the development of efficient NIR-II AIEgens. In this study, a quite strong photothermal agent TPTQ is developed via rational design, which involves planarizing acceptor and π-bridge and rotating donor. The strong electron-withdrawing moiety 6, 7-diphenyl-[1,2,5]thiadiazolo[3,4- g ]quinoxaline is selected as the acceptor and thiophene is fabricated as the π-bridge. The planarization of π-bridge and acceptor units can enhance the intramolecular charge transfer effect, which makes TPTQ possess a long imaging wavelength longer than 1300 nm. Moreover, phenothiazine is utilized as the donor and triphenylamine is engineered on the donor part as a rotor to optimize the AIE-active characteristic and photothermal conversion efficiency of TPTQ. Notably, the TPTQ nanoparticles (NPs) achieve the highest photothermal conversion efficiency of 73.32% among the reported photothermal agents with NIR-II fluorescence imaging capability. Extensive tests in vivo indicate that the constructed TPTQ NPs can not only serve as a superior NIR-II fluorescence imaging (FLI) for the blood vessels of mice but also be successfully applied in 4T1 tumor-xenografted mice for the outstanding photothermal imaging (PTI), demonstrating distinguished FLI-guided photothermal tumoricidal capability. Herein, the smart design of acceptor/π-bridge planarization and donor rotation provide a new approach of developing highly effective NIR-II photothermal therapeutic agents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four homologous luminogens with AIE characteristics through acceptor substitution engineering were developed. • The four photosensitizers showed excellent ROS generation capacities and different organelle targeting abilities. • TBVP targeting cellular membrane exhibited the strongest antitumor PDT efficiency. Photodynamic therapy (PDT) is a promising noninvasive treatment for cancer. Researchers have focused on improving the therapeutic effects of PDT in recent years. Subcellular organelles are the building blocks of cells, and their destruction can lead to cell dysfunction or even death. Photosensitizers (PSs) with precise organelle targeting capacity can not only kill cancer cells effectively but also help reduce PS dose, minimize side effects, and avoid drug resistance. Herein, four homologous luminogens with aggregation-induced emission (AIE) characteristics through acceptor substitution engineering are designed and synthesized to specifically anchor to mitochondria, cell membrane and lysosome through slight structural tweaks, and reactive oxygen species (ROS) are efficiently produced under light irradiation, which significantly enhance the therapy efficacy of PDT. Notably, biological studies have shown that membrane-targeted PS, TBVP exhibits more powerful therapeutic effects than other three PSs (TBPy , TBPy-Bu and TBPy-TA) at the same concentration. The highly effective anti-tumor activity of TBVP was evaluated successfully in vitro and in vivo. In addition, TBVP can promote cell autophagy to induce cell death. We thus believe the anchoring organelles approach described here represents an attractive therapeutic approach in photodynamic therapy. [ABSTRACT FROM AUTHOR]

Abstract: Three novel metal-free organic dyes with dihydro-5H-dibenzo[b,f]azepine as a donor and cyanoacrylic acid as an anchoring unit were designed as an innovative linear skeleton of D–D–π–A type of organic dyes. The conversion efficiency of the derived dye-sensitized solar cells is moderate. Among them, the dye with a hydroxy group as an additional anchoring moiety exhibited the highest UV–Vis absorption with a maximum molar extinction coefficient of 24,136 M−1 cm−1 at λ max = 458 nm and the best photovoltaic performance with an overall power conversion efficiency of 4.88%, while the dye with a carboxy group as an additional anchoring moiety exhibited the lowest conversion efficiency (4.52%). The results show that the dye loading on the film and photovoltaic performance of the dyes were influenced by the additional anchoring units. [Copyright &y& Elsevier]

Photodynamic therapy (PDT) is a promising treatment for cancer, but still faces challenges. For example, the residual photosensitizers (PSs) can cause toxic effects on normal tissues. Thus, it is of great importance to change the PS into safe compounds in or after PDT process. In this work, a novel PS NTPy was synthesized and successfully applied for cancer therapy. NTPy with aggregation-induced emission (AIE) characteristics shows high reactive oxygen species generation efficiency and exhibits a strong fluorescence emission in 678 nm. In addition, NTPy shows excellent mitochondria targeting capacity. In hypoxic microenvironment, NTPy is degraded into TPy via the reduction caused by nitroreductase. TPy shows very little PDT activities and low fluorescence emission. Therefore, NTPy can detect the hypoxic microenvironment of tumor through fluorescence "turn-off" response. More importantly, NTPy can reduce the side effects of PS on normal tissues after effective PDT treatment. This work provides a new strategy for intelligent PDT treatment and increases the biological safety of PDT. • A new aggregation-induced emission (AIE) photosensitizer NTPy was developed. • NTPy showed excellent mitochondria targeting and high ROS generation capacities. • NTPy could be degraded into TPy via the reduction by NTR in hypoxic condition. • TPy showed very little PDT activity and low fluorescence emission. [ABSTRACT FROM AUTHOR]

Development of multifunctional probes that can be simultaneously utilized for both efficient hydrogen sulfide detection and photodynamic therapy in cancer cells is in high demand but remains worldwide challenge. Herein, a fluorescent probe DB2T based on a BODIPY structure for H 2 S fluorescence "turn-on" detection together with light sensitive anticancer capacity has been designed and synthesized. The probe DB2T features high selectivity towards H 2 S, excellent low detection limit (6.39 nM), and good biocompatibility. Importantly, the probe DB2T has been satisfactorily applied in fluorescence imaging of exogenous H 2 S in zebrafish, and successfully employed in fluorescence imaging of endogenous H 2 S in HCT116 cell and tumor tissues. Moreover, evaluation of the phototherapy effect demonstrates that the probe DB2T performs well as a photosensitizer for photodynamic ablation of HCT116 cancer cells upon white light irradiation. This work should facilitate significant advances in rational design of fluorescence systems for H 2 S detection and even in the diagnosis and treatment of H 2 S related diseases. [Display omitted] • A novel fluorescent probe DB2T for hydrogen sulfide detection was developed. • DB2T can detect H 2 S with excellent selectivity and low detection limit (6.39 nM). • DB2T can detect endogenous H 2 S in HCT116 cell with fluorescence turn-on. • DB2T performs well for photodynamic therapy of HCT116 cancer cells. [ABSTRACT FROM AUTHOR]

• A new near-infrared probe DBT for H 2 S detection was developed. • DBT can detect H 2 S with high selectivity and good sensitivity. • The detection limit of DBT for H 2 S was 6.74 nM. • DBT can be applied in endogenous H 2 S imaging in HCT116 cell with turn-on emission. Hydrogen sulfide (H 2 S) plays a significant role in many pathological and physiological processes in living system. It is of great importance to develop effective fluorescent probes for H 2 S detection with good sensitivity and high selectivity. In this work, we developed a new near-infrared (NIR) fluorescent probe DBT for H 2 S detection with fluorescence turn-on performance. For probe DBT , triphenylamine combined with BODIPY is used as the fluorophore and 2, 4-dinitrophenylsulfonyl group is acted as the reaction site. The results show that DBT exhibits excellent sensing characters toward H 2 S with rapid response (within 150 s), excellent sensitivity (detection limit of 6.74 nM) and good selectivity. Importantly, this probe is also successfully applied in the fluorescent imaging of endogenous H 2 S in HCT116 cells. The outcomes indicate that the probe DBT is a valuable tool for H 2 S detection in solution and living cells. [ABSTRACT FROM AUTHOR]