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Metalloviologens, as emerging electron-transfer photochromic compounds, have shown intriguing properties such as radiochromism, photochromism and photoconductance. However, only a limited number of them have been reported so far. Exploration of new metalloviologens is strongly desired. Herein, we report a new solvothermally synthesized metalloviologen complex [CdCl2(ND)2]n (1, ND = 1,5-naphthalenes) that exhibits photochromic and intrinsic white light emission properties. Density functional theory calculation results reveal that the photochromism could be assigned to photoinduced electron transfer from chlorine atoms to ND molecules. The photoinduced charge-separated states are heat/air stable, attributed to the delocalization of ND and strong intermolecular π–π interactions. Besides, complex 1 consistently emits intrinsic white light when excited with 340–370 nm UV light, achieving high color rendering index (CRI) values (82.54–94.04). By adjusting the excitation wavelength, both "warm" and "cold" white light emission can be produced, making it suitable for the application of a white light emitting diode (WLED). Thus, this work demonstrates that the ND-based metalloviologen is not only helpful in producing photochromism, but also beneficial for creating white-light emission. [ABSTRACT FROM AUTHOR]

Optofluidic laser (OFL) technology, as an emerging technology combining microfluidics and laser technology, offers many unique advantages in sensing applications and has become a research hotspot for highly-sensitive intracavity biochemical analysis. Biochemical sensors based on OFLs can detect changes in biochemical parameters by using significant changes in laser output characteristics, so as to achieve high detection sensitivity. Here, we provide an overview of OFLs with a focus on their constructions, the design of OFL-based biochemical sensors, and their applications in biochemical analysis. Firstly, the three elements of an OFL, including the optical microcavity, gain medium, and pump source, are described systematically. After explaining the basic principles and characterization of OFLs for biochemical sensing, the current research progress of OFL-based biochemical sensors is summarized and analyzed according to the combination of OFLs with different assay techniques. This is followed by a discussion of the research on OFLs at the level of biological macromolecules, cells, and tissues. Finally, in view of the applications of OFLs in the field of biochemical sensing, the current challenges and future development directions are briefly discussed. [ABSTRACT FROM AUTHOR]

Organic compounds are capable of generating hydroxyl radicals (˙OH) through their excited triplet states in natural water. It is of significance to reveal the underlying mechanism of the generation and obtain the generation quantum yield of ˙OH from organic compounds for better understanding of its involvement in indirect photochemical processes in the environment. In this study, the ˙OH quantum yields (Φ˙OH) of 20 organic compounds were determined by photochemical experiments. The calculated Φ˙OH values for the selected organic compounds vary from (1.2 ± 0.39) × 10−5 to (7.2 ± 0.16) × 10−4. A quantitative structure–activity relationship (QSAR) model for log Φ˙OH was developed and the established model was proven to have a proper goodness of fit, robustness, and predictive ability. The QSAR model was successfully used to predict the Φ˙OH value of organic pollutants. Mechanistic interpretation showed that the electron distribution and the electronegativity of organic compounds are the most important factors that determine the generation of ˙OH. The results are helpful for understanding the generation mechanism of ˙OH from organic compounds and also provide insights into the generation of ˙OH from dissolved organic matter in natural water. [ABSTRACT FROM AUTHOR]

An innovative three-dimensional (3D) TiO2 photoelectrode with multilevel facet heterojunctions (FHs) is rationally designed based on in situ 1D rutile TiO2 nanorods with top {111} facets on a Ti mesh substrate. The 3D configuration composed of nanosheets and nanorods is provided with large specific area. The stepped band structure of the multilevel FH gives further impetus to spatial charge separation. The obtained FH-{111}TiO2/Ti photoelectrode achieves a 100% removal of bisphenol A (BPA) in only 20 min and presents an outstanding stability even after 10 cycles. Briefly, this work provides a reference pathway for the highly efficient removal of BPA. [ABSTRACT FROM AUTHOR]

We report a novel {001}TiO2/Ti photoelectrode by directly constructing "mirror-like" TiO2 microspheres on a Ti foil substrate (M-{001}TiO2/Ti). It presents highly enhanced PEC oxidation capability of DMP wastewater, which is mainly attributed to the significant synergetic effects of high exposure of {001} facets and equivalent {001}/{101} facet junctions. [ABSTRACT FROM AUTHOR]

Nowadays, groundbreaking strategies are urgently needed to address drug resistance, osteolysis, bone defects and other predicaments impeding the therapeutic efficacy of osteosarcoma. Among them, photothermal therapy (PTT), using systematically administrated nanoagents, exhibits attractive therapeutic efficacy, yet is powerless in bone defect regeneration. Herein, a novel multifunctional beta-tricalcium phosphate (β-Ca3(PO4)2, β-TCP) bioceramic platform-coated with carbon aerogel (CA), which was initially developed for tumor therapy, was fabricated. On account of the desirable photothermal capabilities of CA, sufficient hyperthermia is generated under the irradiation of an 808 nm laser to achieve a thorough ablation of osteosarcoma tumors. Furthermore, CA-coated surfaces provide extra roughness and a higher specific surface area, which promoted the protein recruitment ability and osteogenesis via a fibronectin (FN)-mediated signaling pathway. The photothermal therapeutic efficacy and osteogenesis capability of CA-coated β-TCP-C suggests a novel approach for the treatment of osteosarcoma and provides provoking inspiration for the prospective bio-application of CA. [ABSTRACT FROM AUTHOR]

Estuarine waters of variable compositions are sinks for many micropollutants. The varying water properties can impact the photodegradation of organic pollutants. In this study, the combined effects of dissolved organic matter (DOM), pH, ionic strength, and halides on the photodegradation of the model organic pollutant oxytetracycline (OTC) were investigated. Suwannee River natural organic matter (SRNOM) was used as a representative DOM. The results showed that the observed photolysis rate constant (kobs) of OTC increased rapidly upon increase of pH. SRNOM induced a 11.0–17.9% decrease of the kobs for OTC. In the presence of SRNOM, the ionic strength and specific halide effects promote OTC photodegradation with a 39.2–84.2% and 7.1–28.8% increase of the kobs, respectively. The effects of SRNOM, ionic strength and halides on OTC photodegradation are pH-dependent. Direct photolysis half-lives (t1/2) of OTC were estimated in view of the more important role of direct photolysis compared to indirect photolysis. The estimated t1/2 values decreased from 187.4–206.6 d to 34.4–36.6 d as the pH increases in the Yellow River estuarine region. The results of this research demonstrate that the photodegradation rate of OTC increases rapidly in the gradient from river water to marine water in estuarine regions. [ABSTRACT FROM AUTHOR]

Photonic crystal (PC) cavities, which possess the advantages of compactness, flexible design, and suitability for integration in a lab-on-a-chip system, are able to distinguish slight variations in refractive index with only a small amount of analyte. Combined with the newly proposed optofluidic technology, PC-cavity devices stimulate an emerging class of miniaturized and label-free biochemical sensors. In this review, an overview of optofluidic PC cavities based biochemical sensors is presented. First, the basic properties of the PC, as well as the sensing principle of the PC cavity, are discussed. Second, the applications of the sensors in detecting gas, liquid, and biomolecule concentrations are reviewed, with a focus on their structures, sensing principles, sensing properties, advantages, and disadvantages. Finally, the current challenges and future development directions of optofluidic PC-cavity-based biochemical sensors are discussed. [ABSTRACT FROM AUTHOR]

Photochemical transformation of hydroxylated polyhalodiphenyl ethers (HO-PXDEs) has attracted much attention for their ubiquitous presence and the photochemical formation of highly toxic dioxins. Dissolved organic matter (DOM) plays an important role in the environmental photochemical transformation of organic pollutants. However, the effects of DOM on the photolysis kinetics and dioxin formation of HO-PXDEs are still not fully understood. Herein, the effects of Suwannee River natural organic matter (SRNOM) on the phototransformation of 2′-HO-2,4,4′-trichlorodiphenyl ether (triclosan) and 2′-HO-2,4,4′-tribromodiphenyl ether (2′-HO-BDE-28) were investigated in artificial estuarine water (AEW). The results showed that although SRNOM induced indirect photolysis of triclosan and 2′-HO-BDE-28, it decreased the observed photolytic rate constants due to light screening, static quenching and dynamic quenching effects. The above effects were quantified firstly. Direct photolysis is more important than indirect photolysis in the transformation of the target compounds and the production of dioxins. SRNOM increased the dioxin yields of the two HO-PXDEs. It was also found that SRNOM decreased the formation rate constant (kp) of 2,8-dichlorodibenzo-p-dioxin (2,8-DCDD) from triclosan and showed no obvious influence on the kp of 2,8-dibromodibenzo-p-dioxin (2,8-DBDD) from 2′-HO-BDE-28. SRNOM showed no obvious influence on the degradation of 2,8-DCDD, while it increased the degradation rate constant of 2,8-DBDD. The promoting effect on the degradation of 2,8-DBDD was attributed to the formation of chloride radicals with the concurrence of SRNOM and Cl− in AEW. This study revealed the roles of SRNOM in the photochemical transformation of HO-PXDEs and the photochemical formation and degradation of dioxins, which is important for elucidating the transformation fate of HO-PXDEs in aquatic environments. [ABSTRACT FROM AUTHOR]

A solar-driven dual photoelectrode photocatalytic fuel cell (PFC) based on n-type semiconductor photoanode and p-type semiconductor photocathode is reported for wastewater treatment with simultaneous hydrogen production. The PFC shows a superior performance for phenol degradation and hydrogen production with a maximum TOC removal rate of 84.2% and a total hydrogen production rate of 86.8 μmol cm−2 in 8 hours which is much higher than other similar researches. Compared to the system comprised of a photoanode (photocathode) and Pt for phenol degradation (hydrogen production), the results prove that there is a synergistic effect between the two photoelectrodes. This is because the electrons are preferentially stored on the photocathode for hydrogen production and holes on the photoanode for pollutant degradation. Several semiconductors are chosen as photoelectrodes to investigate the factors influencing the performance of the PFC system. The VOC value of the PFC increases with the difference of Fermi level between the two photoelectrodes. This PFC system provides a new approach for efficient energy recovery from wastewater. [ABSTRACT FROM AUTHOR]

A series of new metal–organic coordination complexes, [Zn(cpds)(H2O)2]n(1), {[Zn(cpds)(4,4′-bipy)]·6H2O}n(2), {[Zn(cpds)(bpe)]2·0.5(bpe)·4H2O}n(3), [Cu(cpds)(2,2′-bipy)(CH3OH)]2·2H2O (4), {[Cu(cpds)(4,4′-bipy)(H2O)2]·2.24H2O}n(5), {[Cu(6-sinic)(4,4′-bipy)0.5]·CH3OH·H2O}n(6), [Cd2(6-mna)2(phen)]n(7), and {[Cd(cpds)(bpe)]·2.2H2O}n(8) were prepared by self-assembly of disulfide derivative of the nicotinate, 6,6′-dithiodinicotinic acid (H2cpds) with transition metal ions in the absence of different N-donor ligands (4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy= 2,2′-bipyridine, phen = 1,10-phenanthroline, bpe = 1,2-bis(4-pyridyl)ethene, 6-sinic = 6-sulfinto-nicotinate, 6-mna = 6-mercaptonicotinic acid). X-Ray structure analyses of 1–8reveal their structure ranging from the discrete unit (0D) (4), one-dimensional (1D) (1, 5), two-dimensional (2D) (7), non-interpenetrating 3D porous coordination polymers (6, 8), 2-fold interpenetrated structure (2) to a 5-fold interpenetrating framework (3), which mainly due to the differences in the bridging modes of cpds2−and the effect of the secondary ligands. Interestingly, in the complexes 6and 7, the starting H2cpds reagent is converted into new ligands (6-sinic in 6and 6-mna in 7) under solvothermal condition viain situcleavage of S–S bond. In addition, thermogravimetric analyses, X-ray powder diffractions and the fluorescent properties of complexes 1, 2, 3, 7, 8have been investigated. [ABSTRACT FROM AUTHOR]

A series of new metal–organic coordination complexes, [Zn(cpds)(H2O)2]n(1), {[Zn(cpds)(4,4′-bipy)]·6H2O}n(2), {[Zn(cpds)(bpe)]2·0.5(bpe)·4H2O}n(3), [Cu(cpds)(2,2′-bipy)(CH3OH)]2·2H2O (4), {[Cu(cpds)(4,4′-bipy)(H2O)2]·2.24H2O}n(5), {[Cu(6-sinic)(4,4′-bipy)0.5]·CH3OH·H2O}n(6), [Cd2(6-mna)2(phen)]n(7), and {[Cd(cpds)(bpe)]·2.2H2O}n(8) were prepared by self-assembly of disulfide derivative of the nicotinate, 6,6′-dithiodinicotinic acid (H2cpds) with transition metal ions in the absence of different N-donor ligands (4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy= 2,2′-bipyridine, phen = 1,10-phenanthroline, bpe = 1,2-bis(4-pyridyl)ethene, 6-sinic = 6-sulfinto-nicotinate, 6-mna = 6-mercaptonicotinic acid). X-Ray structure analyses of 1–8reveal their structure ranging from the discrete unit (0D) (4), one-dimensional (1D) (1, 5), two-dimensional (2D) (7), non-interpenetrating 3D porous coordination polymers (6, 8), 2-fold interpenetrated structure (2) to a 5-fold interpenetrating framework (3), which mainly due to the differences in the bridging modes of cpds2−and the effect of the secondary ligands. Interestingly, in the complexes 6and 7, the starting H2cpds reagent is converted into new ligands (6-sinic in 6and 6-mna in 7) under solvothermal condition viain situcleavage of S–S bond. In addition, thermogravimetric analyses, X-ray powder diffractions and the fluorescent properties of complexes 1, 2, 3, 7, 8have been investigated. [ABSTRACT FROM AUTHOR]

An innovative three-dimensional (3D) TiO2 photoelectrode with multilevel facet heterojunctions (FHs) is rationally designed based on in situ 1D rutile TiO2 nanorods with top {111} facets on a Ti mesh substrate. The 3D configuration composed of nanosheets and nanorods is provided with large specific area. The stepped band structure of the multilevel FH gives further impetus to spatial charge separation. The obtained FH-{111}TiO2/Ti photoelectrode achieves a 100% removal of bisphenol A (BPA) in only 20 min and presents an outstanding stability even after 10 cycles. Briefly, this work provides a reference pathway for the highly efficient removal of BPA.

We report a novel {001}TiO 2 /Ti photoelectrode by directly constructing "mirror-like" TiO 2 microspheres on a Ti foil substrate (M-{001}TiO 2 /Ti). It presents highly enhanced PEC oxidation capability of DMP wastewater, which is mainly attributed to the significant synergetic effects of high exposure of {001} facets and equivalent {001}/{101} facet junctions.

Photonic crystal (PC) cavities, which possess the advantages of compactness, flexible design, and suitability for integration in a lab-on-a-chip system, are able to distinguish slight variations in refractive index with only a small amount of analyte. Combined with the newly proposed optofluidic technology, PC-cavity devices stimulate an emerging class of miniaturized and label-free biochemical sensors. In this review, an overview of optofluidic PC cavities based biochemical sensors is presented. First, the basic properties of the PC, as well as the sensing principle of the PC cavity, are discussed. Second, the applications of the sensors in detecting gas, liquid, and biomolecule concentrations are reviewed, with a focus on their structures, sensing principles, sensing properties, advantages, and disadvantages. Finally, the current challenges and future development directions of optofluidic PC-cavity-based biochemical sensors are discussed.

A series of new metal-organic coordination complexes, {[Ni(IP)(H(2)O)(4)].(2H(2)O)(SO(4))} (1), [M(IP)(mu(2)-SO(4))(H(2)O)(2)] (M = Zn 2 , and M = Mn 3 ), {[M(2)(IP)(2)(mu(2)-SO(4))(2)(H(2)O)(4)].2H(2)O} (M = Zn 4 , and M = Co 5 ), {[Mn(2)(IP)(mu(2)-SO(4))(H(2)O)(2)].(6.5H(2)O)(sdba)} (6), {[Mn(IP)(2)(H(2)O)(2)][Mn(pydc)(2)(H(2)O)(2)].(4H(2)O)} (7), {[Mn(IP)(fum)(H(2)O)].H(2)O} (8), {[M(3)(IP)(3)(fum)(3)].(8H(2)O)} (M = Cd 9, and M = Zn 10 ), {[Cd(2)(IP)(2)(bptc)(H(2)O)(2)].(7.3H(2)O)} (11), {[Zn(2)(IP)(2)(bptc)(H(2)O)(2)].(3H(2)O)} (12), {Cd(1,4-BDC)(IP)(H(2)O)].(0.5H(2)O)} (13), {[Mn(1,4-BDC)(IP)(H(2)O)].H(2)O} (14), {[Zn(2)(1,4-BDC)(2)(IP)].2.5H(2)O} (15) (IP = 1H-imidazo[4,5-f][1,10]-phenanthroline, H(2)sdba = 4,4'-sulfonyldibenzoic acid, H(2)pydc = pyridine-2,6-dicarboxylic acid, H(2)fum = fumaric acid, H(4)bptc = 3,3',4,4'-benzophenonetetracarboxylic acid and 1,4-H(2)BDC = 1,4-benzendicarboxylic acid) were prepared via self-assembly of pharmaceutical agent IP with different metal sulfates in the absence/presence of the carboxylate under mild conditions. All these compounds were structurally determined by single-crystal X-ray diffraction. Compounds 2-6 crystallize with N-donor chelating ligands and sulfate anion linkers. Complexes 2-6 possess sulfate anions with mu(2)-bridging modes, the roles of sulfate anions result in 1D chains (2 and 3) and dinuclear units (4, 5and 6). For complex 7 , two different Mn units are chelated by two IP and pydc ligands, respectively. Compound 8 is a 1D chain connected by fum ligands. Polymers 9-12 exhibit 2D network structures composed of tetrametallic and hexametallic clusters. The Cd(ii)/Zn(ii) layers are interdigitated in pairs for complexes 11 and 12 by stacking forces, which exhibit unusual 2D-->3D interdigitated architectures. In 13 and 14, they show 1D undulating and linear chains due to the different coordinate modes of 1,4-BDC. IP firstly acts in a tridentate mode via the two N atoms of pyridyl rings and the third N atom of imidazole ring, and the two carboxylate groups of 1,4-BDC ligand taking three types of coordinative modes connect Zn atoms into a complicated 3D network in 15 . The structural differences among complexes 1-15 indicate the backbone of such dicarboxylate ligands, nature of metal resources and the ratio of metal to ligand play important roles in modulating the formation of the coordination polymers. Thermal stabilities of these crystalline materials, fluorescent properties of these complexes and TD-DFT calculation of spectra of IP were also investigated.