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In this work, LiYF4:Yb0.253+/Er0.013+/Tm0.013+/Ho0.013+@LiYF4:Yb0.23+ upconverting nanoparticles (UCNP) were used as luminescent materials for the preparation of molecular imprinting polymer nanocomposites. Three luminescent molecularly imprinted polymer (MIP) nanocomposites were prepared by in situ polymerization. The relationship between the functional monomers, templates, and upconversion nanoparticles was investigated. Two hydrophilic monomers (acrylic acid (AA) and acrylamide (AAm)) and one hydrophobic monomer (N-tert-butylacrylamide (TBAm)) were employed as functional monomers, while one amino acid (cysteine) and two proteins (albumin and hemoglobin) were employed as the templates to investigate the effect of their interaction with LiYF4:Yb3+/Er3+/Ho3+/Tm3+@LiYF4:Yb3+ core/shell UCNPs on the polymerization process, luminescence properties, and adsorption capacity. The results showed that the UCNPs were embedded in the polymeric matrix to form an irregular quasimicrospherical UCNPs@MIP with diameters ranging from several hundred nanometers to several micrometers depending on the functional monomer. The quenching effect was more pronounced for the adsorption of hemoglobin with UCNPs@MIP compared to cysteine and albumin. In addition, the adsorption capacities of the AA- and AAm-made UCNPs@MIP were greater than those of TBAm-made UCNPs@MIP. The rebinding of the templates onto UCNPs@MIP was very fast and approached equilibrium within 30 min, indicating that the synthesized UCNPs@MIP can be employed as fluorescent probes to offer rapid detection of molecules.

A fluorescent probe for specific biorecognition was prepared by a facile method in which amphiphilic random copolymers were encapsulated with hydrophobic upconversion nanoparticles (UCNPs). This method quickly converted the hydrophobic UCNPs to hydrophilic UNCPs. Moreover, the self-folding ability of the amphiphilic copolymers allowed the formation of molecular imprinting polymers with template-shaped cavities. LiYF4:Yb3+/Tm3+@LiYF4:Yb3+ UCNP with up-conversion emission in the visible light region was prepared, this step was followed by the synthesis of an amphiphilic random copolymer, poly(methacrylate acid-co-octadecene) (poly(MAA-co-OD)). Combining the UCNPs and poly(MAA-co-OD) with the templates afforded a micelle-like structure. After removing the templates, UCNPs encapsulated with the molecularly imprinted polymer (MIP) (UCNPs@MIP) were obtained. The adsorption capacities of UCNPs@MIP bound with albumin and hemoglobin, respectively, were compared. The results showed that albumin was more easily bound to UCNPs@MIP than to hemoglobin because of the effect of protein conformation. The feasibility of using UCNPs@MIP as a fluorescent probe was also studied. The results showed that the fluorescence was quenched when hemoglobin was adsorbed on UCNPs@MIP, however, this was not observed for albumin. This fluorescence quenching is attributed to Förster resonance energy transfer (FRET) and overlap of the absorption spectrum of hemoglobin with the fluorescence spectrum of UCNPs@MIP. To our knowledge, the encapsulation approach for fabricating the UCNPs@MIP nanocomposite, which was further used as a fluorescent probe, might be the first report on specific biorecognition.

We report the synthesis of lanthanide-doped core/shell upconverting nanoparticles (UCNPs) LiYF4:Yb3+/Er3+/Ho3+/Tm3+@LiYF4:Yb3+. The photoluminescence (PL) spectra of the tetragonal-phase nanoparticles could be tuned by varying the doping ratio of lanthanide ions (Er3+, Ho3+, Tm3+) and their intensities were much enhanced through the active core/active shell strategy. The as-synthesized UCNPs were characterized and confirmed by X-ray diffraction (XRD), transmission electron microscope (TEM), and PL spectroscopy. By varying the composition and concentration of the dopant ions, the upconversion emissions upon near-infrared (NIR) excitation at 980 nm can be precisely modulated. After overcoating UCNP cores with LiYF4:Yb3+ shell, the upconversion emissions for all core/shell nanoparticles were about 3 times of those corresponding core nanoparticles. After ligand exchange, the hydrophobic LiYF4:Yb3+/Er3+/Ho3+/Tm3+@LiYF4:Yb3+ core/shell nanoparticles could be transferred into hydrophilic UCNPs. The colloid nanoparticles could be employed as a chemosensor for detection of Hg2+ at near-infrared excitation wavelengths.

White light-emitting diodes (LEDs) have been achieved using photopolymerization. Red and green CdSe/ZnS core–shell quantum dots (QDs) are dispersed in photopolymerized aliphatic acrylic acrylate resins, cured by using 36 W UV light for 1.5 min producing QD–acrylate nanocomposites, and then a hybrid LED device is achieved using the QD–acrylate nanocomposite with two emission wavelengths excited by using a blue InGaN LED chip. The cured QD–acrylate nanocomposite films are characterized by using ultraviolet–visible, fluorescence, scanning electron microscopy, atomic force microscopy, and thermogravimetric analysis measurements. Photopolymerization is conveniently employed to adjust several parameters of the CIE-1931 coordinate (x, y), color temperature, and color rending index (CRI). Good white balance of the red-green hybrid device achieves a luminance of 7976 lm/m2 at a 30 mA working current. The light emission efficiency, CRI, and color temperature of 14%, 47, and 11 204 K, respectively, are attained at this working current.

An amphiphilic block copolymer (BCP) which contains both photoresponsive and thermoresponsive blocks was synthesized by the atom transfer radical polymerization approach. Meanwhile, a new core/shell type of the upconversion nanoparticle (UCNP) LiYF4:Yb3+0.25,Tm3+0.01@LiYF4:Yb3+0.2 was successfully synthesized. By encapsulating UCNPs inside the micelles of the BCP and incorporating Nile red (NR) into the UCNP@BCP hybrid nanoparticles as a model drug, controlled release of the drug by the dual-stimuli BCP could be studied. After exposing the UCNP-loaded micellar solution to near-infrared (NIR) light, it was found that the UV light pumped from UCNPs could disrupt the polymer micelles and the fluorescence intensity of NR decreased with the increase of the irradiation time of the NIR light. The thermoresponsive study indicated that the fluorescence intensity of NR decreased with the increase of temperature of the micellar solution because of the release of NR into water arising from the contraction of the amphiphilic BCP.

Molecularly imprinted polymer (MIP)-based electrochemical sensors for the protein α-synuclein (a marker for Parkinson's disease) were developed using a peptide epitope from the protein. MIPs doped with various concentrations and species of transition metal dichalcogenides (TMDs) to enhance conductivity were electropolymerized with and without template molecules. The current during the electropolymerization was compared with that associated with the electrochemical response (at 0.24~0.29 V vs. ref. electrode) to target peptide molecules in the finished sensor. We found that this relationship can aid in the rational design of conductive MIPs for the recognition of biomarkers in biological fluids. The sensing range and limit of detection of TMD-doped imprinted poly(AN-co-MSAN)-coated electrodes were 0.001-100 pg/mL and 0.5 fg/mL (SNR = 3), respectively. To show the potential applicability of the MIP electrochemical sensor, cell culture medium from PD patient-specific midbrain organoids generated from induced pluripotent stem cells was analyzed. α-Synuclein levels were found to be significantly reduced in the organoids from PD patients, compared to those generated from age-matched controls. The relative standard deviation and recovery are less than 5% and 95-115%, respectively. Preparation of TMD-doped α-synuclein (SNCA) peptide-imprinted poly(AN-co-MSAN)-coated electrodes.

The level of C-reactive protein (CRP) in serum is frequently used to evaluate risk of coronary heart disease, and its concentration is related to cardiovascular disease, fibrosis and inflammation, cancer, and viral infections. In this work, three novel peptides, never previously used as imprinted templates, were selected, synthesized, and employed for epitope imprinting. Various imprinting concentrations of the template and various ratios of aniline (AN) to m-aminobenzenesulfonic acid (MSAN) were used in electropolymerization to form molecularly imprinted polymers (MIPs). The imprinting template and functional monomer concentrations were optimized to maximize the electrochemical response to target peptides. The surface morphologies of peptide- and non-imprinting poly(AN-co-MSAN) were observed using a scanning electron microscope (SEM) and an atomic force microscope (AFM). Moreover, the effect of doping of MIPs with a very small percentage of an MXene (e.g. Ti

In this work, LiYF

Molecularly imprinted polymers (MIPs) can often bind target molecules with high selectivity and specificity. When used as MIPs, conductive polymers may have unique binding capabilities, they often contain aromatic rings and functional groups, which can undergo &pi, －&pi, and hydrogen bonding interactions with similarly structured target (or template) molecules. In this work, an electrochemical method was used to optimize the synthetic self-assembly of poly(aniline-co-metanilic acid) and testosterone, forming testosterone-imprinted electronically conductive polymers (TIECPs) on sensing electrodes. The linear sensing range for testosterone was from 0.1 to 100 pg/mL, and the limit of detection was as low as ~pM. Random urine samples were collected and diluted 1000-fold to measure testosterone concentration using the above TIECP sensors, results were compared with a commercial ARCHITECT ci 8200 system. The testosterone concentrations in the tested samples were in the range of 0.33 &plusmn, 0.09 to 9.13 &plusmn, 1.33 ng/mL. The mean accuracy of the TIECP-coated sensors was 90.3 &plusmn, 7.0%.

We have successfully synthesized ternary CdxZn1-xSe alloy quantum dots (QDs) and CdxZn1-xSe/ZnS core/shell nanocrystals. In order to be used as a fluorescent/paramagnetic bi-functional probe, the ZnS shell was doped with 0.1% and 5% of paramagnetic manganese ions. The compositions of Cd, Zn, and Se in the CdxZn1-xSe core QDs were identified by energy-dispersive X-ray spectroscopy (EDS), and the crystal structures of the alloy nanocrystals were identified by wide angle X-ray diffraction (WAXD). The particle size and distribution of nanocrystals were determined by dynamic light scattering (DLS) and transmission electron microscopy (TEM). By varying the ratio of Cd:Zn in the CdxZn1-xSe core, the band gaps of CdxZn1-xSe nanocrystals became adjustable and were in the range of 1.92 eV to 2.72 eV. Hence, the fluorescent color of nanocrystals varied from red to blue in the visible light region. The CdxZn1-xSe/ZnS core/shell nanocrystals exhibited superior photoluminescence (PL) quantum yield up to 50%. Compared with CdxZn1-xSe cores, the PL emission peaks of CdxZn1-xSe/ZnS core/shell QDs are red-shifted. Electron paramagnetic resonance (EPR) measurements for manganese-doped CdxZn1-xSe/ZnS nanocrystals showed paramagnetic properties at both low and high Mn2+ concentrations.

This work studied the effect of self-doped polyaniline (SPANI)-assembled carbon nanoparticles (CNPs) on a supercapacitor. SPANI was in situ polymerised and assembled on CBs by mixing the monomers o-aminobenzenesulphonic acid (SAN) and aniline (AN) with an initiator and CNPs. SAN acted as a self-doped monomer and a surfactant. SPANI-modified CNPs used as an electrode material would improve the performance of CB-based supercapacitor. Variation of the molar ratio of AN/SAN altered the performance of the SPANI–CNP-based supercapacitor. Cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy were employed to investigate the properties of the supercapacitors. The SPANI–CNP-based supercapacitor attained optimal performance at an AN/SAN ratio of 1.0, exhibiting a specific capacitance of 342 Fg− 1 at a charging current density of 0.5 Ag− 1 in a symmetric cell.

Ternary CdSxSe1−x alloy quantum dots (QDs) and CdSxSe1−x/ZnS core/shell nanocrystals exhibiting composition dependent band gaps have been successfully synthesized. The ZnS shell was doped with 0.1% and 5% of paramagnetic manganese ions so as to be used as a fluorescent/paramagnetic bi-functional probe. Energy-dispersive X-ray spectroscopy (EDS) measurements confirmed the presence of Cd, S, and Se in CdSxSe1−x nanocrystals with the atomic ratios of Cd, S, and Se which are well consistent with our synthetic ratios. Wide angle X-ray diffraction (WAXD) indicated that the crystal structures of the CdSxSe1−x core QDs and CdSxSe1−x/ZnS core/shell QDs were zinc blende phases. Both dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed that the as-synthesized nanocrystals had a narrow size distribution and high crystallinity. The band gaps of CdSxSe1−x nanocrystals were adjustable by varying the ratio of S:Se in the CdSxSe1−x core and were in the range of 1.96 eV to 2.32 eV. Hence, when composition x was changed from 0 to 1, the fluorescence color of the nanocrystals varied from red to green. After shell coverage, the ternary alloy QDs exhibited a superior photoluminescence (PL) quantum yield up to 57%. In comparison with the alloy core QDs, the PL emission peaks of the CdSxSe1−x/ZnS core/shell QDs displayed a small redshift. Electron paramagnetic resonance (EPR) measurements for manganese-doped CdSxSe1−x/ZnS nanocrystals revealed paramagnetic properties for both low and high Mn2+ doping levels.

This study develops a dental implant surgery composite material that allows learners to experience the drilling forces necessary to perform drilling into alveolar bone. Organic-inorganic TiO2-acrylate hybrid reactive precursors were first prepared in hydroethylacrylate (HEA) solvent using glycidylmethacrylate cordination-binding sol-gel polymerization of titanium tetrachloride in a simple one-pot hydrolysis process. HEA, used in place of alcohol, served as both of a solvent and a reactive monomer in later photopolymerization. The use of HEA eliminates the need to remove the diluent solvent. An average TiO2 nanoparticle size of about 20−30 nm was measured using dynamic light scattering equipment. The obtained TiO2-acrylate hybrid reactive precursors were mixed with bisphenol-A ethoxylate dimethacrylate and photoinitiators to prepare TiO2-polyacrylate composite films after ultraviolet-light illumination. Experimental results demonstrate that the contact angle of the composite films decreased with increasing TiO2-acrylate hybrid precursor content, whereas the glass transition temperature and hardness of the composite films increased. By varying TiO2- polyacrylate hybrid composition, a alveolar bone model was fabricated. The forces (> 7 N) necessary to drill cortical and cancellous bone were measured.

This work reports on a modularized electrochemical method for the determination of the hormones cortisol, progesterone, testosterone and 17β-estradiol in urine. These hormones were employed as templates when generating molecular imprints from aniline and metanilic acid by electropolymerization on the surface of screen-printed electrodes. The electrically conductive imprint was characterized by SEM, AFM and cyclic voltammetry. A four-channel system was then established to enable simultaneous determination of the hormones by cyclic voltammetry. The detection limits for cortisol, progesterone, testosterone and 17β-estradiol are as low as 2, 2.5, 10 and 9 ag·mL−1 (for S/N = 3).

In this study, a robust high-performance polyaniline-modified graphene electrode is successfully used to assemble a supercapacitor. Graphene is covalently bonded to self-doped polyaniline (SPANI) and used in supercapacitors, and 4-aminobenzoic acid-modified graphene (ABF-G) sheet materials are first bonded to an aniline functional group at graphene edges. Then, aniline, o-aminobenzene sulfonic acid monomers, and an oxidising agent are added into the ABF-G aqueous dispersion to achieve polymerisation on the surface of ABF-G. This covalently bonded SPANI-modified ABF-G (SPANI-ABF-G) thin-film electrode material is then used for fabricating supercapacitors. A Raman spectrometer, a scanning electron microscope, a secondary ion mass spectrometer, an X-ray electron photon spectrometer, and a specific surface area analyser are used to characterise this film. The supercapacitor with the proposed SPANI-ABF-G electrodes exhibits a high specific capacitance value of 642.6 F/g for charging and discharging at a current density of 1 A/g. After 5000 cycle-life testing, this supercapacitor exhibits a charging and discharging capacitance retention of 100% and 98.13% at a current density of 1 and 2 A/g, respectively. These capacitance retentions are higher than those of supercapacitors with conductive polymers electrodes. The results prove that electrode materials prepared using covalently bonded graphene and PANI can considerably improve supercapacitor performance.

Parkinson's disease (PD) is a progressive nervous system disorder that affects movement, whose early signs may be mild and unnoticed. α-Synuclein has been identified as the major component of Lewy bodies and Lewy neurites, which are the characteristic proteinaceous deposits that are the hallmarks of PD. In this work, three alpha-synuclein peptides were synthesized as templates for the molecular imprinting of conductive polymers to enable recognition of alpha-synuclein via ultrasensitive electrochemical measurements. The peptide sequences encompassed specific residues where mutations are known to accelerate PD (though the target sequences, in this study, were wild-type.) The different peptide targets were all successfully imprinted, but with differing imprinting effectiveness, probably owing to differences in target carboxylic acids (which can bind to the aniline (AN) m-aminobenzenesulfonic acid (MSAN) MIP polymers.) Composition of the imprinted polymer, (the mole proportions of AN and MSAN), and the concentrations and sequences of imprinted peptide templates were optimized by measuring the electrochemical responses to target peptides. The imprinted electrode can detect alpha-synuclein at fg/mL levels, and was therefore used to measure alpha-synuclein in the culture medium of human brain organoids generated from normal and idiopathic PD patients.

Herein, we successfully synthesized a series of LaF3:Yb3+/Er3+/Ho3+/Tm3+ upconversion nanoparticles (UCNPs) and LaF3:Yb3+0.20, Er3+0.02@LaF3:Yb3+0.20 core/shell UCNPs by modifying the amount of NaOH and the reaction time. Hexagonal LaF3 nanocrystals with uniform particle sizes and bright UC emissions were obtained. The crystal structures of the lanthanide-doped LaF3 UCNPs were investigated using wide-angle X-ray diffraction. The morphologies and particle sizes of the nanocrystals were determined using transmission electron microscopy. The photoluminescence (PL) spectra of the LaF3 nanocrystals could be tuned by altering the doping ratio of Er3+, Ho3+, and Tm3+. In addition, the PL intensities increased after coating the UCNP cores with an active shell. The fluorescence intensities of the UCNPs synthesized via a one-hour reaction with the addition of 2.5 or 5 mmol NaOH increased by up to 17 times compared with the sample prepared without the addition of NaOH. By modifying the doping ratio of Yb/Tm, UV-emissive LaF3 nanocrystals were obtained. After surface modification by ligand exchange, the hydrophobic LaF3:Yb3+0.20, Er3+0.02@LaF3:Yb3+0.20 core/shell UCNPs became water-dispersible. These colloid UCNPs could be utilized as a fluorescent probe for the detection of Hg2+ ions under 980 nm near-infrared irradiation.

Vinylimidazolium-typed poly(ionic liquids) (PILs) are prepared by photo-polymerization of ionic liquid monomers. Vinylimidazolium-based ionic liquid monomers with C4 and C8 alkyl tail length were synthesized via quaternization of 1-vinylimidazole with corresponding n-alkyl bromides. Polymerization was conducted at a 3 wt.% of photoinitiators in these monomers using illumination of 36 W LED light. In the same procedure, preparation of cross-linked PILs was performed in the presence of 15 mol% of divinylimidazolium-based cross-linker. These PILs are characterized by using chemical structure, physical characteristics, and electrical conductivity. Electrical conductivity of C4-based PILs is greater than that of C8-based PILs, whereas linear PILs are higher than crosslinked PILs. Crosslinked PILs have higher glass transition and thermal decomposition temperatures as compared linear PILs. PILs consist of the repeating units of anion and cation pair. Its nature has moderate electronic conductivity, which is suitable use in gel-type or quasi-solid-state dye-sensitized solar cells (DSSCs). The linear PILs were incorporated in DSSCs obtaining an efficient quasi-solid-state cell to solve the leakage of liquid electrolyte in a liquid-type DSSC.

In this work, progesterone is imprinted into poly(aniline-co-metanilic acid) on the working electrode of an electrochemical sensing chip. This sensing chip was used directly to optimize the composition of the imprinting polymer. Poly(aniline-co-metanilic acid) deposited from a 1 : 3 molar ratio of aniline (ANI) : m-aminobenzenesulfonic acid (MSAN) had an imprinting effectiveness which led to a four-fold greater electrochemical response than pure polyaniline. The electrochemical sensing of progesterone had a limit of detection (LOD) less than 1.0 pg mL−1, and the direct electrochemical response was very weak even at high interference concentrations. Results from potential interferents (urea, testosterone, creatinine and 17-β estradiol) are reported. The progesterone levels that were measured in a random urine analysis were compared with those obtained using a commercial ARCHITECT system, and the accuracy of the progesterone concentration was 89.0 ± 5.3% at a concentration of 0.64–5.27 ng mL−1.

Two conjugated alternating copolymers to be used as the donor materials of the active layers in polymer solar cells have been designed and synthesized via a Stille coupling reaction. The alternating structure consisted of 4,8-bis((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b′]dithiophene (BDT) as the donor unit and benzo[c][1,2,5]thiadiazole (BT) or fluorinated benzo[c][1,2,5]thiadiazole (FBT) as the acceptor unit, along with a thiophene group as the π-bridge between the donor and acceptor units. Since the donor units have attached alkoxy pendant chains, both polymers were soluble in common organic solvents. UV-vis spectra of both copolymers exhibited broad absorption bands in the range of 325–900 and 380–900 nm, respectively, and corresponding low band gaps of 1.82 and 1.80 eV. After fluorination of the BT unit, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of the polymer were lowered and estimated to be −5.51 and −3.71 eV, respectively. It was found that substitution of an F atom into the BT units facilitated the intramolecular charge transfer. In comparison with the nonfluorinated polymer, the photovoltaic performance of the fluorinated polymer was significantly improved due to the enhanced Jsc and Voc. Based on the ITO/PEDOT:PSS/polymer:PC61BM/LiF/Al device structure, the optimal device efficiency was obtained from a device with a blend of PBDTFBT and PC61BM at a weight ratio of 1 : 1. For this blend ratio, the values of Jsc and power conversion efficiency (PCE) obtained at room temperature are 7.98 mA cm−2 and 3.62%, respectively, under the illumination of AM 1.5 (100 mW cm−2).

A series of novel triphenylamine (TPA)-based dyes that use double linkers between the electron donor and the electron acceptor are synthesized, characterized, and applied as photosensitizers for dye-sensitized solar cells. The dyes contain N-methylpyrrole (NMP) (MTPA-2 dye) and styrene (St) (STPA-2 dye), respectively, linkers on TPA. These linkers are expected to generate effective π-conjugation forming donor–π–acceptor (D–π–A) links. The photovoltaic performance of the dyes depends on the linker type. For the dual-St-π-linked dye, the charge transfer from the excited dye molecules to the conduction band of TiO2 is improved, making the efficiency of the corresponding devices higher than those of dye-based devices with NMP linkers and no linkers. The device with the dye bearing positions of C3 and C4 on NMP linkers has the lowest conjugation effect and efficiency. In particular, the STPA-2 dye shows a broad incident-photon-to-current conversion efficiency response with a signal of up to 700 nm, covering most of the ultraviolet-visible light region. Device efficiencies of 5.43% and 7.56% for dye-sensitized devices using the STPA-2 dye and the cis-RuL2(NCS)2 (N3) dye, respectively, were fabricated using the same method and measured under AM 1.5 irradiation.

In this study, two photoswitchable spiropryran-capped hybrid nanoparticles based on two different core/shell upconverting nanoparticles (UCNPs) were reported. Two kinds of LiYF4 core/shell UCNPs doped with Yb3+/Ho3+ and Yb3+/Tm3+ were first prepared and could emit the ultraviolet (UV) and visible light under 980 nm NIR excitation respectively. X-ray diffraction (XRD) and transmission electron microscope (TEM) analysis indicated that both kinds of UCNPs had the tetragonal phase and the single-crystal structure. The photoluminescence (PL) intensities were much enhanced through the active-core/active-shell synthetic strategy. Next, the spiropyran molecules could be coordinated onto the surface of the oleate-capped UCNPs via ligand exchange, which was confirmed by fourier transform infrared (FTIR) spectra. PL spectra for the Ho3+-doped SP-UCNPs hybrid nanoparticles revealed that the green emission band excited by near-infrared (NIR) light could be completely quenched after illuminating SP-UCNPs with UV for 150 s. The cyclical photoswitching tests were further carried out for both kinds of UCNPs by alternating irradiation with UV/visible, UV/NIR, or NIR/visible light. The optical switching of PL intensity of the spiropryran-capped UCPNs did not have apparent decline effect after 10 cycles of on/off test. A reversible photoswitching of the hybrid nanoparticles revealed that both kinds of spiropyran-capped UCNPs had a superior photostability for the biological applications.

Ternary CdS

A photopolymerization method is used to prepare a mixture of polymer ionic liquid (PIL) and ionic liquid (IL). This mixture is used as a solid-state electrolyte in carbon nanoparticle (CNP)-based symmetric supercapacitors. The solid electrolyte is a binary mixture of a PIL and its corresponding IL. The PIL matrix is a cross-linked polyelectrolyte with an imidazole salt cation coupled with two anions of Br− in PIL-M-(Br) and TFSI− in PIL-M-(TFSI), respectively. The corresponding ionic liquids have imidazolium salt cation coupled with two anions of Br− and TFSI−, respectively. This study investigates the electrochemical characteristics of PILs and their corresponding IL mixtures used as a solid electrolyte in supercapacitors. Results show that a specific capacitance, maximum power density and energy density of 87 and 58 F·g−1, 40 and 48 kW·kg−1, and 107 and 59.9 Wh·kg−1 were achieved in supercapacitors based on (PIL-M-(Br)) and (PIL-M-(TFSI)) solid electrolytes, respectively.

In this work, we electrochemically deposited self-doped polyanilines (SPANI) on the surface of carbon-nanoparticle (CNP) film, enhancing the superficial faradic reactions in supercapacitors and thus improving their performance. SPANI was electrodeposited on the CNP-film employing electropolymerization of aniline (AN) and o-aminobenzene sulfonic acid (SAN) comonomers in solution. Here, SAN acts in dual roles of a self-doped monomer while it also provides an acidic environment which is suitable for electropolymerization. The performance of SPANI−CNP-based supercapacitors significantly depends upon the mole ratio of AN/SAN. Supercapacitor performance was investigated by using cyclic voltammetry (CV), galvanostatic charge and discharge (GCD), and electrochemical impedance spectroscopy (EIS). The optimal performance of SPANI−CNP-based supercapacitor exists at AN/SAN ratio of 1.0, having the specific capacitance of 273.3 Fg−1 at the charging current density of 0.5 Ag−1.

A proportional control chart (P chart), a special case of the PID chart arise by setting the chart parameters k I and k D to zero. From the viewpoint of the operators, the use of the complete PID chart is more complicated than that of the P chart, and would only result in a marginal improvement of the detecting ability when the process autocorrelation is very strong or the mean shifts are very large. In the most of literatures, the average run lengths (ARLs) of a PID chart are obtained by simulation technique and used to evaluate the charting performance. But the simulation technique is quite time consume in the case of longer on-target ARL analysis. In the present paper, a simple unified method based on a finite Markov chain approach for evaluating the performance of P chart is developed. The method is implemented by using discretization of control statistic and the finite Markov chain imbedding (FMCI) technique to investigate the ARL of a P chart when the observations have an AR(1) autocorrelated structure. This simple model may be a reasonable model for many processes encountered in practice. The numerical studies show that the approximation results are consistent with the simulation results.

Free-radical polymerization kinetics of N-isopropylacrylamide (NIPAAm) using 2,2′-azobis(isobutyronitrile) (AIBN) as an initiator in supercritical carbon dioxide (scCO2) was investigated. A high-pressure differential scanning calorimeter revealed that the melting temperatures of NIPAAm and AIBN were both decreased with increasing CO2 pressure in a linear fashion and the polymerization could occur in CO2 at 55 °C. The polymerization kinetics of NIPAAm in scCO2 was compared with that in methanol (MeOH). At 55 °C, the induction periods of polymerizations in scCO2 of 27.6 MPa were much longer (up to 6 h) than those in MeOH (about 30 min) for similar feed concentrations. The monomer conversions reached and molecular weights produced were much higher in scCO2 than in MeOH. The reaction orders for initial monomer and initiator concentrations, [NIPAAm]0 and [AIBN]0, in initial stage of polymerizations were respectively 1.48 and 0.79 in scCO2 and 1.27 and 0.51 in MeOH.

A series of side-chain-tethered copolymers containing the N-(2-ethylhexyl)-N′-(thiophene-3-yl)-3,4:9,10-perylenebis(dicarboximide) (thiophene-PDI) moieties and 4,4-diethylhexyl-cyclopenta[2,1-b:3,4-b′]dithiophene unit were synthesized via Grignard metathesis polymerizations. With the incorporation of pendent perylenebis(dicarboximide) (PDI) moieties as acceptor side chains and thiophene as the donor backbone, the copolymers exhibited the intramolecular donor–acceptor characteristic and displayed a panchromatic absorption ranging from 290 to 1100 nm and ideal bandgaps of 1.49 to 1.52 eV. Due to the coplanarity of PDI moieties, the charge separation and transfer process were more effective and enhanced after photoexcitation. When increased the weight ratio of PC61BM:polymer to 3, the Jsc could be raised significantly. The value of bandgap decreased slightly, and both Voc and Jsc showed an upward trend with the increase of molar ratio of thiophene-PDI unit from 50% (the copolymer P11) to 75% (the copolymer P13). The polymer/PC61BM devices have shown a significant improvement from 0.45 to 1.66% with a judicious modulation. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1978–1988

Nitrogen-doped graphene (NDG)/titanium dioxide (TiO2) nanoparticles were coated on indium-tin oxide (ITO) glass substrates to fabricate NDG-TiO2 nanocomposite electrodes. 3-methylthiophene (3MT) was electrochemically deposited on the NDG-TiO2 films to form poly(3-methylthiophene) (P3MT/NDG/TiO2) composite electrochromic electrodes. The introduction of NDG and TiO2 mesoporous films significantly increased the initial maximum optical contrast (ΔT%) to 70% as compared 41% of pure ITO electrodes, whereas the P3MT/NDG/TiO2 composite electrodes enhanced the adhesion of P3MT polymers to the NDG/TiO2/ITO substrate, thereby increasing the long-term stability of the corresponding electrochromic devices. Experimental results reveal that P3MT/NDG/TiO2 composite electrodes retained up to 90% of ΔT%, relative to 70% remaining ΔT% of pure ITO electrodes. This illustrates the enhanced long-term stability achieved through the introduction of a NDG-TiO2 nanocomposite films in electrochromic devices. These devices demonstrated excellent response time characteristics and ΔT% value of 6 s and ca. of 70%, respectively. This work has shown that conductive polymer/NDG/TiO2 composite electrodes are well suited to electrochromic devices for the promotion of performance and stability.

Composites of Nafion, COOH-capped CdSe, and self-doped polyaniline (SPAN) were used to prepare novel chemical modified glassy carbon electrodes (Nafion/CdSe/SPAN/GCE). The electrocatalytic activities of the modified GCE to the redox reactions of dopamine (DA), uric acid (UA), and ascorbic acid (AA) were investigated by cyclic voltammetry (CV). CV curves revealed that the electrocatalytic activities of Nafion/CdSe/SPAN/GCE to oxidations of the analytes in solution of pH 7 were in the order of DA > UA > AA. This order was consistent with the strong-to-low extent of interactions between the modified GCE and the analytes. These interactions were consistent with the observations that the oxidation rate of DA followed a diffusion-controlled process whereas that of UA followed a surface adsorption-controlled process. The composites of casting at higher pH levels were found to exhibit better CdSe and SPAN dispersions in films and higher electrocatalytic activities. CdSe and SPAN exhibited insignificant synergistic effects on the oxidations of DA when cast from Nafion solutions of both low and high pHs whereas CdSe and SPAN exhibited much synergistic effects on the oxidations of UA when cast from the Nafion solution of high pH at 12.

This study presents a two-stage hydrothermal process to synthesize anatase TiO 2 nanoparticles. The first stage formed sodium titanate (Na 2 Ti 9 O 19 ). Octahedral TiO 6 in Na 2 Ti 9 O 19 shares crystal edges similar to those of octahedral TiO 6 in anatase TiO 2 . This study used Na 2 Ti 9 O 19 as an intermediary to generate pure anatase TiO 2 . The second stage involves disintegrating the structure of the Na 2 Ti 9 O 19 crystals through an ion exchange of Na + in Na 2 Ti 9 O 19 with H + in HNO 3 , resulting in the formation of pure anatase TiO 2 nanoparticles (7 to 10 nm). The static (acid addition) and space repulsion (binder addition) methods (surface area with BET = 81.594 m 2 g −1 ) were used to hinder the coalescence of TiO 2 nanoparticles. The proposed approach produces well-dispersed nanoparticles compared to the method using only static repulsion (surface area with BET = 68.071 m 2 g −1 ). These two TiO 2 materials were used to prepare photoelectrodes with a film thickness of approximately 6 μm in dye-sensitized solar cells (DSSCs), which achieved device efficiencies of 6.23% and 4.66%, respectively.

Composites of self-doped polyaniline (SPAN), chitosan (CS), and carbon nanotubes (CNT) (or COOH-functionalized CNT, denoted by fCNT) were cast on glassy carbon electrodes (GCE) via different casting procedures for investigations on their apparent electrocatalytic activities in buffer solutions of pH 2, 7, and 11 using the Fe(CN) 6 3-/4- redox couple as a probe by cyclic voltammetry (CV). CV curves revealed that the cast CS–CNT and CS–fCNT composites both exhibited apparent electrocatalytic activities to the reactions of the probe at pH 2 and 7. The SPAN was found to exhibit synergistic effects with (f)CNT on the apparent electrocatalytic activity, with CNT exhibiting higher synergism than fCNT. SPAN in the outer layer of the SPAN/CS–(f)CNT/GCE exhibited more enhanced apparent electrocatalytic activity than that in the inner layer of the CS–(f)CNT/SPAN/GCE or that being mixed in the CS–(f)CNT–SPAN/GCE. At pH 7, the layered SPAN/CS–CNT/GCE and CS–CNT/SPAN/GCE that exhibited fairly high apparent electrocatalytic activities to the redox reactions of the probe exhibited also high apparent electrocatalytic activities to the oxidation reactions of dopamine (DA) and uric acid (UA) and were suitable for their detections. The layered SPAN/CS–fCNT/GCE and CS–fCNT/SPAN/GCE, and the non-layered CS–(f)CNT–SPAN/GCE exhibited low anodic peak current densities and were not suitable for the detections of both analytes.