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Color-tunable dual-mode organic afterglow excited by ultraviolet (UV) and white light was achieved from classical aggregation-caused quenching compounds for the first time. Specifically, two luminescent systems, which could produce significant organic afterglow composed of persistent thermally activated delayed fluorescence and ultralong organic phosphorescence at ambient conditions, were constructed by doping fluorescein sodium and calcein sodium into aluminum sulfate. Their lifetimes surpassed 600 ms, and the dopant concentrations were as low as 5[[EQUATION]]10-6wt%. Moreover, the persistent luminescence colors of the materials could be tuned from blue to green and then to yellow by simply varying the concentrations of guest compounds or the temperature in the range of 260~340 K. Inspired by these exciting results, the afterglow materials were used for UV- and white-light-manipulated anti-counterfeiting and preparation of elastomers with different colors of persistent luminescence.

The development of circularly polarized thermally activated delayed fluorescence (CP-TADF) luminogens with stimuli-response characteristics remains challenging. Herein, a pair of organic enantiomers, S -CzTA and R -CzTA, with aggregation-induced emission properties, have been successfully developed by introducing chiral 1,2,3,4-tetrahydronaphthalene and carbazole to phthalimide. They present CP-TADF properties in toluene solutions, giving dissymmetric factors of 0.84×10 -3 and -1.03×10 -3 , respectively. In the crystalline state, both S -CzTA and R -CzTA can emit intense blue TADF and produce very bright sky-blue mechanoluminescence (ML) and remarkable mechanofluorochromism (MFC) under the stimuli of mechanical force. Single-crystal analysis and theoretical calculation results suggest that their ML activities are probably associated with their chiral and polar molecular structures and unique noncentrosymmetric molecular packing modes. Furthermore, the MFC properties of the enantiomers likely originate from the destruction of crystal structure, leading to the planarization of molecular conformation. This work may provide helpful guidance for developing new CP-TADF materials with force-stimuli-responsive properties.

A pair of axially chiral organic enantiomers were facilely prepared through a one-pot sequential synthesis. They exhibit circularly polarized luminescence activities and have thermally activated delayed fluorescence (TADF) and aggregation-induced emission enhancement properties. Meanwhile, these two enantiomers present remarkable and reversible thermochromism in the crystalline state, enabling dual-colour TADF switching between orange and red. However, when they form cocrystals, the resulting racemate shows opposite thermochromic behaviors. These intriguing results probably emanate from their different optical activities, leading to distinct molecular packing modes and molecular conformation variations. Moreover, information encryption based on thermochromism of organic enantiomers and their racemate has been presented for the first time. This work may expand the application scope of chiral organic luminogens and pave a new way to construct intelligent luminescent systems., A pair of axially chiral organic enantiomers with circularly polarized thermally activated delayed fluorescence and aggregation-induced emission enhancement properties show opposite thermochromic behaviors to their racemate.

The interaction of the newly approved pharmacon esketamine with HSA (human serum albumin) has been investigated by various spectrographic methods. The fluorescence quenching results of HSA by esketamine revealed that the 1:1 ground state complex has formed. The results of binding parameters lead to the conclusion that the reaction was exothermic. In the presence of esketamine, HSA was found to undergo partial unfolding, and thermodynamic parameters (ΔG° = − 2.08 × 104 J·mol−1, ΔS° = 35.7 J·mol−1·K−1, and ΔH° = − 1.20 × 104 J·mol−1 at 298 K) revealed that electrostatic forces dominated the stabilization of the complex. The qualitative and quantitative analyses of conformational changes of HSA were conducted using circular dichroism, three-dimensional, and synchronous fluorescence spectroscopy, revealing the loosening of skeleton structure and adaptive modifications of secondary structures. Fe3+ and Mg2+ may help prolong the storage time and improve the drug efficacy.

It remains a great challenge to develop polymer-based materials with efficient and color-tunable organic afterglow. Two indolocarbazole derivatives IaCzA and IbCzA have been synthesized and doped into poly(vinyl alcohol) (PVA) matrices. It is found that the resulting films can produce unique dual-mode afterglow, which is composed of persistent thermally activated delayed fluorescence and ultralong organic phosphorescence. Besides, the IbCzA-doped PVA film exhibits intense blue afterglow with Φ

Flexible, stretchable and sensitive textile-based sensors play important roles in a wide variety of artificial intelligence because of its seamless integration with clothing and good comfort. Herein, MXene sensing layer is deposited on the surface of springlike helical core-sheath polyester yarns thanks to the capillarity effect and its intrinsic hydrophilic ability, and the resultant strain sensor and humidity sensor exhibit wide detection range from 0.3 to 120% strain and 30–100% relative humidity (RH) detection, owing to elastic core-sheath structures. The strain sensor shows excellent reproducibility (over 10000 cycles) and fast response time (120 ms). The core-sheath yarn sensor can detect various human motions such as walking, bending and twisting as well as physiological signal (pulse), which have great potential in real-time precise medicine and health care. The yarn sensor could also be an excellent humidity sensor because of the high specific area structure of yarn and intrinsic hydrophilic properties of MXene sensing layer.

The development of a sensitive flexible wearable temperature sensor has extraordinary significance in the field of human vital signs detection. Herein, we demonstrate a flexible temperature sensor (FTS) fitting on human skin based on non-woven fabric, and it has been systematically characterized and tested for performance. The resistor-type FTS integrated sodium alginate with graphene, behaved as negative temperature coefficient feature and exhibited excellent sensing performance of good sensitivity (TCR = − 1.5 °C−1), high accuracy of 0.1 °C, short response time (26.3 s), high stability and repeatability at the temperature range of 20.0–45.0 °C. Specially, the FTS eliminated strain and humidity interference, so that can be attached to the human body to detect skin temperature changes continuously and stably.

Stretchable electrical conductors have demonstrated promising potentials in a wide range of wearable electronic devices, the conductivity of most of reported stretchable conductive fibers will be changed if be stretched or strained. But however, stable conductance is essential for wearable and stretchable device, to ensure the performance of wearable devices is stable. Inspired by the peristaltic behavior of arthropods, we designed a graphene coating similar to the caterpillar structure on the PU fiber surface, enabled by coating the worm-shape graphene microlayer onto polyurethane filaments. Such worm-shape filaments can be stretched up to 1010% with wide reversible electro-response range (04000 stretching/releasing cycles), good initial conductivity (σ0=124 S m-1) and high-quality factor (Q=11.26). Remarkably, the worm-shape filaments show distinctive strain-insensitive behavior (ΔR/R0

The in situ construction of gas sensors is of great significance to obtain the desired structure of a sensing film with enhanced performance. In this work, an electrodeposition-based method was employed to in situ construct a ZnO-ordered macroporous film resistive-type gas sensor for the first time. A ceramic tube was used as the substrate and coated with graphite as an auxiliary conductive layer. By electrodeposition co-induced by a two-dimensional colloidal crystal template and sodium dodecylsulfate, metallic Zn standing nanosheets and Zn(OH)2 shells were grown around template microspheres. Then, by heat treatment in air, a ZnO-ordered macroporous film gas sensor was obtained. The film possessed a novel and unique structure composed of a monolayer macropore array and standing nanosheets integrated into the interstices among the macropores. The growth of pore-walls and nanosheets, as well as the morphology and sensing response of the final film, is controlled by the electrodeposition time. Given the synergy between the macroporous structure and the standing nanosheets, the sensing response of this ZnO film to ethanol gas was considerably enhanced compared with that of the film with only a macroporous structure, the film with only standing nanosheets, and the film without these two structures. Moreover, the sensor also exhibited a ppb-level detection limit, excellent reversibility, long-term stability and good selectivity. This method provides new approaches for constructing gas sensors with a uniform surface morphology and obtaining high sensing performance by constructing an ordered collocated structure.

Background: To investigate the clinical value of HE4 detection in the diagnosis of lung cancer and the clinical significance of combined detection with CEA, NSE and CYFRA21-1. Methods: 90 cases of lung cancer, 30 cases of pulmonary tuberculosis, 30 cases of pneumonia and 30 cases of health physical examination were selected. The levels of serum HE4, CYFRA21-1, CEA and NSE were detected by electrochemiluminescence method. Statistical analysis was performed to observe the sensitivity and specificity. Results: The levels of serum HE4, CEA, NSE and CYFRA21-1 in lung cancer group were significantly higher than those in tuberculosis group and health physical examination group. There was no significant difference in the levels of HE4, CEA and NSE between the lung cancer group and the pneumonia group, the difference of CYFRA21-1 level was statistically significant (p

A new micro/nano-structured material, mesoporous CuS hollow spherical cap (HSC), was fabricated on the surface of a solution by template-induced interfacial reaction. The Cu2(OH)2CO3 microspheres modified with vinyl trimethoxy silane were floated on the mixed aqueous solution of ethanol and thioacetamide, and acted as the template and the copper source. At the solid-liquid interface thioacetamide reacted with Cu2(OH)2CO3 to produce CuS shells around the immersed part of the template, and then the mesoporous CuS HSC was obtain by removal of the template. Controlling the content of ethanol could systemically tune the immersed depth and the HSC height. Such HSCs displayed increased photocatalytic activity in degradation of methyl blue with the decrease of the HSC height. In addition to the conventional specific surface area, the activity regions accessible by light (light receiving region) were analyzed by optical simulation for the first time and considered an important factor in enhancing the photocatalytic activity of HSC structure. The present study not only shows a facile strategy to fabricate activity-tunable CuS HSC photocatalyst, but also establishes a relationship between the geometry of morphology and photocatalytic performance.

Fast fashion, as a continuously growing part of the textile industry, is widely criticized for its excessive resource use and high generation of textiles. To reduce its environmental impacts, numerous efforts are focused on finding sustainable and eco-friendly approaches to textile recycling. However, waste textiles and fibers are still mainly disposed of in landfills or by incineration after their service life and thereby pollute the natural environment, as there is still no effective strategy to separate natural fibers from chemical fibers. Herein, a green chemistry strategy is developed for the separation and regeneration of waste textiles at the molecular level. Cellulose/wool keratin composite fibers and multicomponent fibers are regenerated from waste textiles via a green chemical process. The strategy attempts to reduce the large amount of waste textiles generated by the fast-developing fashion industry and provide a new source of fibers, which can also address the fossil fuel reserve shortages caused by chemical fiber industries and global food shortages caused by natural fiber production.

A dual-pKa values pH fluorescence probe based on pyrene, N-(2′-morpholinoethyl)-pyrene-1-carboxamide (MPCA), was fabricated through facile one-step reaction. Interestingly, MPCA showed a pKa1 of 1.88 under extremely acidic conditions and a pKa2 of 5.81 under weak acidic conditions in deionized water, which indicate that MPCA has a high sensitivity to change of pH value. When the pH value was decreased further from 4.05 to 0.52, the fluorescence response of MPCA was quenched by 93.8% due to quenching of fluorescence emission of the pyrene monomer and apparent conversion of monomer/excimer of pyrene group. The results show that pyrene excimer of MPCA can be produced in extremely acidic environment. When the pH value of the solution was decreased from 7.03 to 4.05, the fluorescence response of MPCA was enhanced due to the inhibition of photoinduced electron transfer (PET) from N atom on morpholine ring to pyrene fluorophore. In addition, MPCA has a short response time, good repeatability and anti-cation interference for pH monitoring. MPCA was then applied successfully to monitor the acidity of environmental water systems (tap water and Pearl River water) and the living GS cells of epinepheluscoioides. Finally, a fluorescence pH test paper based on the colorful changes of MPCA at different pHs was developed, which can conveniently monitor the pHs of aqueous solutions.

Dual-mode persistent luminescence and helical-array-induced mechanoluminescence (ML) are observed for the first time from two different polymorphs (SCp and SCb) of a pair of AIE-active enantiomers, respectively. The impressive afterglows from the SCp crystals of (R)-ImNCz and (S)-ImNCz are composed of persistent thermally activated delayed fluorescence and ultralong organic phosphorescence, and their colours can be tuned from yellow to sky blue by temperature in a mild window from 0 °C to 100 °C. In particular, the SCp crystals of (S)-ImNCz present relatively stable warm-white afterglows at around room temperature. The generation of dual-mode persistent luminescence from SCp crystals is probably associated with the charge separation and recombination as well as the small ΔEST values of enantiomer molecules and the strong intermolecular interactions in crystal structures. On the other hand, the conspicuous ML of (R)-ImNCz and (S)-ImNCz from SCb crystals likely results from their helical arrays and notable AIE properties, enabling the formation of crystals with polar space groups and high fluorescence quantum yields. The results from this polymorphic system may provide useful guidance for the development of new organic emitters with innovative applications.

A room-temperature photochemical method was introduced to fabricate SnO 2 -reduced graphene oxide (SnO 2 -rGO) composite with a new type of structure. SnO 2 dense layers were directly grown on the two sides of an rGO sheet through ultraviolet light (UV) irradiation of a mixed precursor solution of SnSO 4 , H 2 SO 4 , and graphene oxide for 6 h. The composite possessed a novel flat flake-like structure consisting of two SnO 2 dense layers and an rGO sheet sandwiched in between. In contrast to most graphene-based composites, the fabricated composite was non-flexible, wrinkle-free and rGO surfaces were completely covered. The composite could be used in photocatalysis and exhibited remarkably enhanced activity in degradation of p -nitrophenol under low intensity of UV light or sunlight. The activity was more than 12 times that of pure SnO 2 and considerably higher than that of other SnO 2 -rGO composites. The dense layer immobilized the flat structure, promoted the photocatalytic activity, and maintained the long-term stability of the composite. After preservation of more than 12 months in ambient condition, the composite showed a nearly constant activity. This photochemical method can be used to fabricate graphene-based composites with regular structure, high performance, and long-term stability.

We sought to evaluate the activity and safety of these novel proteasome inhibitors (PIs) (carfilzomib, ixazomib, oprozomib and marizomib) containing regimens (single, doublet and triplet) for relapsed/refractory multiple myeloma (R/RMM).We searched published reports including these novel PIs containing regimens for R/RMM.Finally, we identified 28 prospective studies that evaluated 4123 patients. Pooled analysis showed that novel PIs doublet combinations attained an impressive overall response rate (ORR) of 67%, which was higher than that of 22% from novel PIs single-agent (p .001). And, the same trends favoring novel PIs doublet combinations were also shown in at least very good partial response (≥VGPR) and clinical benefit rate (CBR) analysis. Meanwhile, the ORR of 70% from novel PIs triplet regimens seemed to be similar to that of 67% from novel PIs doublet combinations (p = .54). And, there were no difference between them in ≥VGPR and CBR analysis. Compared to standard therapy, novel PIs combinations clearly benefited patients with R/RMM in terms of overall survival (HR, 0.79; p= .01), progression free survival(HR, 0.64; p = .01), overall response rate (RR = 1.21 p .001).Novel PIs doublet combinations attained superior response outcomes over novel PIs single-agent in patients with R/RMM. Meanwhile, novel PIs triplet combinations had similar response outcomes with novel PIs doublet combinations. Compared to standard therapy, novel PIs combinations clearly prolonged survival for patients with R/RMM.

A highly selective and sensitive fluorescent ratiometric probe (1) based on pyrene-containing Schiff base for the dection of Cu2+ was synthesized. In acetonitrile–HEPES buffer solution (20.0 mM HEPES, 8:2, v/v, pH 7.4), only Cu2+, out of tested common cations, could induce the aggregation of probe 1. Fluorescence analysis showed that the excimer emission band of pyrene groups of probe 1 appeared and gradually increased with the addition of Cu2+. The fluorescent intensity ratio of excimer and monomer (I470/I409) of probe 1 increased 27.8-fold upon the addition of one equiv. of Cu2+ with a detection limit of 20.2 nM (1.28 ppb). The addition of Cu2+ also induced obvious color change and the characteristic peaks of pyrene excimer in UV–vis spectrometra of the relutant solution. Results from the Job plot, metal-binding fluorescent titration, mass spectra experiments and density functional theory calculations indicated a binding ratio of 2:1 (probe 1: Cu2+). In addition, probe 1 showed good potential as a fluorescent visualizing probe for the detection of Cu2+ in living GS cells of epinepheluscoioides.

Developing effective and feasible treatment methods to address high-risk emerging contaminants is a tremendous and persistent challenge to environmental safety. Bisphenol AF (BPAF), one of the most often used bisphenol A (BPA) alternatives, has a higher lethality, estrogenic activity, and developmental toxicity than BPA, and is difficult to decompose, yet studies to remove BPAF are very limited. Herein, by analysis and design of band structure, single bulk-doped, single surface-doped, and bulk and surface dual-iodine-doped BiOIO3 photocatalysts are fabricated via modifying pristine BiOIO3 using ion exchange or/and in situ reduction strategies. The respective role and synergistic effect of iodine doping at different locations of BiOIO3 are then discussed. As dual doping mode affords a high iodine content, rich oxygen vacancies, and more dispersed band structure, the as-synthesized dual-iodine-doped BiOIO3 exhibits strong visible-light absorption (from UV to ~ 750 nm), strong oxidation ability (valence band potential of 2.68 V), and efficient charge separation kinetics, resulting in an excellent visible-light photocatalytic activity for BPAF degradation. After 2 h of photoreaction, the degradation percentage and TOC reduction of BPAF reach 96.5% and 94.0%, respectively, which far exceed those of BiOIO3, BiOI, or single iodine-doped BiOIO3. The radical trapping experiments and EPR analysis reveal that h+, e−, O2−, OH, and 1O2 are all involved in the catalytic process. The reaction intermediates are identified, and a reasonable photocatalytic mechanism is proposed. In addition, the synthetic dual-iodine-doped photocatalyst maintains stability during photoreaction and is successfully applied to a real wastewater sample, demonstrating its potential in practical applications.

Visible light photocatalysis driven via ligand-to-metal charge transfer (LMCT) can provide a new opportunity for solar energy utilization, yet investigations on non-TiO2 catalysts are rather limited and the mechanism of LMCT remains unclear. This study focused on the controllable synthesis, applications, and LMCT photosensitization mechanism of bismuth-based materials. BiOIO3, with tunable surface-exposed Bi(III), was first synthesized by a facile hydrothermal route and then applied to visible light photocatalytic decomposition of six dihydroxybenzoic acids (DHBAs) to optimize the conditions of surface complexation and photosensitization. After that, nine additional DHBA analogues and seven bismuth-based semiconductors with different crystal and band structures were used as alternative ligands and modified materials, respectively, to verify and support the hypothesis. It was found that organics with an ortho-dihydroxyphenyl substructure could chelate well with Bi(III) to form colored metal-organic complexes and caused the formation of surface oxygen vacancies (OVs) in the semiconductors, which resulted in the structural dependence and selective photocatalytic properties over the catalysts. In addition, the obtained materials could be used as either normal visible-light-driven photoelectric conversion materials or photocatalysts for environmental contaminants removal through producing highly reactive •OH, O2−, and 1O2 oxygen species. Theoretical calculations were performed to analyze the coordination, light absorption, molecular orbitals, and band structures of the complexes. With reference to the principles of semiconductor heterojunction, a novel visible-light-sensitization mechanism for small-molecule surface-modified bismuth-based semiconductors was proposed. The results develop the LMCT mechanism and significantly extend the applications of semiconductor photocatalytic materials.

Se-rGO composite photocatalyst was prepared by photochemical method and improved Hummers method. The morphology and structure of the photocatalyst were characterized by SEM and XRD. The photocatalytic properties of the composite were studied by degrading RhB under UV light. The results showed that the composite retained the original mophorlogy of selenium and graphene oxide after compounding, where a large number of spherical Se particles are clustered and loaded on the surface of GO layers; hexagonal phase is observed in the pattern of pure Se, and the crystalline structure remains unchanged after compounding GO. The photocatalytic activity of the composite is more than twice as high as that of the pure Se. Moreover, the photocatalytic activity of the photochemical prepared Se-rGO composite is much higher than that of the mechanically mixed Se/GO. Se-rGO composite has good photocatalytic performance and the degradation process conforms well to the first-order reaction kinetics. The degradation rate of RhB solution can reach 76.8% after 120 minutes of UV irradiation.

Background Lentiviral vectors (LVs) have enhancer activity and/or transcriptional read-through (EATRT) properties that can lead to the activation of adjacent genes. Consequently, patients may be at increased risk for adverse effects if such vectors are used clinically. Methods In the present study, we assessed the abilities of different "pro-LV"-like constructs with respect to decreasing its EATRT, including the "pro-LV" vector bearing a chimeric ΔLTR of the human foamy virus R-U5 region replaced by that of an LV (HF). Results By analyzing the EATRT of "pro-LV" constructs transfected in 293T cells, we observed that the inclusion of the first 400 bp of the chicken β-globin locus HS4 insulator core sequence oriented in the reverse direction (C-) combined with two copies of the simian virus 40 upstream-sequence element (U) at the ΔU3 of ΔLTR region of "pro-LV" tended to shield the adjacent genomic sequences, such that the EATRT rate was lower than when either of the C- or U was included in the "pro-LV". Moreover, upon transduction, the pro-HF appears to reduce the EATRT rate in the chromosomes of 293T (by 80%) and human peripheral blood mononuclear cells (PBMCs) (by 75%) compared to when pro-LV C-U was included (with a 60% and 89% reduction in 293T and PBMCs, respectively). The HF construct had a significant reduction of viral biological titer compared tiowhen the pro-LV C-U was used in 293T cells. Conclusions The results of the present study provide an important basis for the clinical applicability of LVs in gene and cell therapy.

For the construction of a resistive-type gas-sensor, it is usually required for a sensing film to be fabricated on a non-conductive substrate. The in situ construction of a sensor by subjecting the substrate to an electrodeposition method is impossible and there have been no related reports on this. Herein, taking the in situ construction of a SnO2 film sensor as an example, a novel electrodeposition-based method was introduced. A conductive graphite coating was firstly fabricated on the non-conductive substrate for the implementation of the electrodeposition, and then a calcining process was employed. The conductive pristine graphite coating was found to become non-conductive after being calcined for more than 70 min at 500 °C, resulting in the final electrodeposited film being able to work as a sensing film. Some important parameters related to the sensing performances, including the formation, the conductivity, the electrodeposition time, the calcining time and the working temperature, were systematically studied. Under the optimal conditions, the SnO2 film sensor exhibited high sensitivity, a fast response and recovery, and long-term stability in the detection of ethanol gas with concentrations ranging between 1–100 ppm. The electrodeposition-based method is reproducible, mass-productive and general. It is therefore practical and promising for the construction of various semiconductor film sensors.

Micro/nanostructured silver particles with different shapes (flower, wire, and rod) have been prepared and characterized. All the open aperture z-scan curves of silver microrods and silver nanoflowers present a typical reverse saturable absorption. With the increase of incident intensity, the nonlinear absorption coefficients and the third-order optical susceptibilities ImX(3) of nanoflowers increase, but those of silver microrods decrease. Moreover, the silver nanowires show the conversion from saturable absorption to reverse saturable absorption. There was no definite correlation between incident intensity and nonlinear absorption coefficient (β) under the conditions studied herein. And nonlinear optical properties of micro/nanostructured silver particles are dependent on the particle shape in suspensions at 800 nm.

Nanoporous SnO2 fine particles with controlled specific surface area were prepared in the SnSO4 and H2SO4 mixed solutions by a simple photochemical method for the first time. Compared with other solution methods, the controlling of surface area can be manipulated at room temperature without the addition of any surfactant or template. Only by controlling the concentration of H2SO4, the specific surface area of the product could be tuned in the range of 13–203 m2 g−1. They showed high activity and can be applied to efficient photocatalytic degradation of dye pollutants under a low power (8 W 254 nm) UV lamp. It was found the activity gradually increased with the increase of the specific surface area or the increase of the concentration of H2SO4 employed in the preparation process. The formation of SnO2 and pore structures, the morphologies, the compositions and the photocatalytic degradation mechanisms were systematically studied.

SnO2 nanoparticles were prepared by a photochemical method with different concentrations of PVP as surfactant. The PVP can put regular impact on the size of the particles and the corresponding sensing response to alcohol gas. The optimized sensor of the SnO2 nanoparticles could exhibit a response of ~21 to 50 ppm alcohol at 270 °C, which is more than 2-folds of that without PVP. The sensor also had excellent stability, repeatability and concentration linear, exhibiting good practicality in alcohol detection. The method is easily-manipulated, low-cost and green for obtaining a gas sensing material.

Graphical abstract: - Highlights: • Photocatalytic activity of Cu{sub 2}O octahedral microcrystals on ITO glass was studied. • They showed high abilities in degradation of methylene blue in the presence of H{sub 2}O{sub 2}. • H{sub 2}O{sub 2} amount could affect the degradation efficiency. • Such particles could be easily recycled and still kept high activity. • Many dye pollutants and their mixtures could be efficiently degraded. - Abstract: Cu{sub 2}O octahedral microcrystals were prepared on the ITO glass by galvanostatic electrodeposition in CuSO{sub 4} solution with poly(vinylpryrrolidone) as the surfactant. By controlling the electrodeposition time, the microcrystals could be randomly distributed on the ITO glass and separated from each other, resulting in as many as possible (1 1 1) crystalline planes were exposed. Such microcrystals immobilized on ITO glass were employed in photodegradation of dye pollutants in the presence of H{sub 2}O{sub 2} under a 150 W halogen tungsten lamp. The photodegradation of methylene blue was taken as an example to evaluate the photocatalytic activities of the octahedral Cu{sub 2}O microcrystals. Effects of electrodeposition time and H{sub 2}O{sub 2} amount on the degradation efficiency was discussed, giving the optimum conditions and the corresponding degradation mechanism. The catalyst showed highmore » ability in degradation of methylene blue, methyl orange, rhodamine B, eosin B and their mixtures under identical conditions.« less

Photo-initiated dispersion polymerization, a photochemical method for preparing poly (styrene-co-maleic anhydride) microspheres, is introduced for the first time in this paper. Ultraviolet lamp, ethanol/water mixture, 2,2-azobisisobutyronitrile, and poly (vinylpyrrolidone) were respectively used as the light source, green solvent, initiator, and stabilizer in the preparation. After careful study of the influencing factors, formations, sizes and size distributions of the microspheres were found to systematically vary with light intensity and amount of reagents used. Under the optimal conditions, microspheres with the narrowest size distribution and sizes smaller than 1 μm were obtained. Based on the functional groups contributed by the MAH, an important application of the prepared microspheres in Ni2+ adsorption was explored. Adsorption capacities were controlled by the MAH amount added in the microsphere preparation.

Octahedral Cu 2 O particles were prepared on an indium-tin oxide glass via electrodeposition and were employed in the catalytic degradation of p -nitrophenol in the presence of H 2 O 2 . Under irradiation of a warm visible-light source, tungsten halogen lamp, Cu 2 O particles not only acted as a photocatalyst, but might also act as a thermal-catalyst to induce the decomposition of H 2 O 2 and produce O 2 at higher temperatures. The photogenerated electrons and holes could react with H 2 O 2 , O 2 , and H 2 O to produce abundant OH radicals, resulting in the effective oxidation of p -nitrophenol. High-performance liquid chromatography measurements of degradation intermediates showed that p -nitrophenol was first decomposed into hydroquinone and benzoquinone and then mineralized. The degradation efficiency was dependent on electrodeposition time, light intensity, H 2 O 2 amount, and solution temperature. This catalyst could be easily recycled and used in the efficient degradation of other phenolic compounds.

Morphology-controlled Cu 2 O microcrystalline particle films had been successfully electrodeposited on tin-doped indium oxide glass substrates in CuSO 4 solutions containing different amounts of polyethylene glycol (PEG) additives. With an increase of PEG, microcrystals gradually changed from irregular shapes to cubes, octahedrons, and spherical shapes. Sizes increasingly became smaller with an increase of PEG under the same deposition time. These films had been first used as recyclable photocatalysts and showed excellent and photocatalytic activities in photodegradation of methylene blue (MB) under sunlight. Activities were regularly varied relative to the morphologies of films controlled by the amount of PEG and could be further enhanced by adding a little amount of hydrogen peroxide in the MB solution. The method for controllable preparation of Cu 2 O microcrystals with photocatalytic activities was simple and inexpensive. The as-prepared particle films could also be used in photodegradation of many other pollutants under sunlight.

A new general method for the fabrication of a reduced graphene oxide (rGO)-based ordered monolayer macroporous film composed of a layer of closely arranged pores is introduced. Assisted by the polystyrene microsphere monolayer colloid crystal by a simple solution-heated method, pure rGO, rGO-SnO2, rGO-Fe2O3, and rGO-NiO composite monolayer ordered porous films were examplarily constructed on the curved surface of a ceramic tube widely used in gas sensors. The rGO-oxide composite porous films could exhibit much better sensing performances than those of the corresponding pure oxide films and the composite films without the ordered porous structures in detecting ethanol gas. The enhancement mechanisms induced by distinctive rGO-oxide heterojunctions and porous structures as well as the effects of the rGO content and the pore-size on the sensitivity of the composite films were systematically analyzed and discussed. This study opens up a kind of construction method for an rGO-based composite film gas sensor with uniform surface structures and high performance.

Taking the poly(styrene-co-acrylamide) (P(St-AM)) as a model material, a novel two-step photochemical method was introduced to construct nanoporous polymer microspheres at room temperature. Under ultraviolet light irradiation, suspensions composed of Cu/Cu2O nanoparticles were first prepared in an alcohol solution of acetylacetonate and benzophenone. Subsequently, the monomers were photopolymerized around the nanoparticles in the suspension-added precursor solution to form polymer–nanoparticle composite microspheres. Nanoporous polymer microspheres could then be obtained by removing the particles with acid. The products had been investigated by XRD, SEM, TEM, IR, DSC, and BET. Results showed the typical microspheres had diameters of 200~300 nm, and the specific areas and pore volume regularly varied with the quantity of the suspensions. By the optimum control, porous P(St-AM) microspheres with average pore size of 5.7 nm, pore volume of 0.18 cm3/g, and specific surface area of 123.54 m2/g could be obtained. The method represents a new, easily manipulated, cost-effective, and safe route for preparation of porous polymer microspheres using inorganic porogens.

Spindly cupric oxide (CuO) micro-particles were synthesized using Cu(NO 3 ) 2 , hexamethylenetetramine, and NaOH solutions at 95 °C. The spindly CuO particles had a shape similar to a carambola of ∼1 μm in length and 300 nm in width. They were composed of nanosheets with a thickness of ∼5 nm. Such particles could be used in the photocatalytic degradation of rhodamine B in the presence of ∼0.01 M H 2 O 2 . Under irradiation by a 100 W halogen tungsten lamp, the CuO showed photocatalytic activities higher than those of P25 and commercially available CuO powder. They were very stable and could be recycled without considerable loss of activity. Other dye and organic pollutants such as methyl orange, methylene blue, erosin B, and p-nitrophenol could also be photodecomposed under identical conditions. These characteristics show the practical applications of the CuO particles in environmental remediation.

Arrayed porous iron-doped TiO2 with controllable pore size was prepared by using polystyrene spheres and its structure, morphology, composition and photoelectrochemical properties were characterized with X-ray diffraction, scanning electron microscope, inductively coupled plasma-atomic emission spectrometer and electrochemical methods. It is found that the photoelectrochemical properties of the arrayed porous TiO2 can be improved by doping adequate amount of iron in the lattice of TiO2 and the sample doped with 0.01 wt% Fe (based on Ti) exhibits the best photoelectrochemical performance. With doping 0.01 wt% Fe in TiO2, the photocurrent density of the sample is improved from 2.0 μA cm−2 to 10.0 μA cm−2 and its flat-band potential shifts from −0.38 V to −0.55 V (vs. SCE).

Arrayed porous iron-doped TiO2 was prepared by sol–gel with polystyrene spheres as template and used as photocatalyst for the degradation of methyl orange. The structure and performances of the prepared photocatalyst were characterized with X-ray diffractometer, inductively coupled plasma-atomic emission spectrometer, scanning electron microscope, UV-visible spectrometer, and methyl orange degradation tests. It is found that the iron dopant does not change the crystal phase of TiO2 but affects its lattice constant, optical absorption, electronic conductivity, charge-transfer resistance, and activity toward the degradation of methyl orange. The sample doped with 0.01 wt.% Fe (based on Ti) and with smaller pore size exhibits the better photocatalytic activity. The degradation rate of methyl orange on the sample with a pore size of 190 nm is 2.3 times that on the undoped sample with the same pore size.