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Farming fisheries are popular in Penghu, and traditional fisheries require a lot of manpower and time. This research integrates thermometer, pH meter, dissolved oxygen meter, and water quality sensor into a circuit board, and transmits the sensed value to the server. User can obtain the real-time information of fish farm through the mobile APP

In this work, a novel electrochromic device (ECD), consisting of phenyl viologen (PV) as the cathodically coloring material and 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as the stable radical provider for charge balance, was proposed. Nanofibers (NFs) obtained by electrospinning, using poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and poly(oxyethylene)-imide imidazolium tetrafluoroborate (POEI-IBF4), were introduced into the electrolyte to absorb tetrabutylammonium tetrafluoroborate and propylene carbonate, so as to form a solid-state electrolyte for the ECD. The NFs were characterized by distribution of their diameters, or histograms, based on the scanning electron microscope (SEM) images; their physical properties, including electrolyte uptake, ionic conductivity, and porosity were studied. The proposed ECDs were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), UV–visible spectra, and dynamic transmittance curves. The pertinent N15P10-ECD exhibited a high transmittance change (ΔT) of 68.7% at 590 nm, while maintaining a good cycling stability (95.5% of its original ΔT) after continuous 1000 switching cycles of operation at room temperature.

Three novel polymeric ionic liquids (PILs), denoted as PFII-F, PFII-E, and PFII-S, are successfully synthesized by grafting different molar ratios (one-fourth, one eighth, and one sixteenth, respectively) of 1-butylimidazolium iodide onto poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP). These PFII PILs are fabricated as polymer membranes via a simple electrospinning technique, which are used as the electrolyte for quasi-solid-state (QSS) dye-sensitized solar cells (DSSCs). The PFII membranes have multiple functions including: (1) encapsulation of the liquid electrolyte with good charge transfer and ionic conductivity properties, (2) chelation of Li+ through the lone pair electrons on their fluoride atoms, and (3) filling the dye-uncovered TiO2 surface with their imidazolium segment. Function (1) endows DSSCs with prominent long-term stability, while functions (2) and (3) suppress the dark current. The best QSS-DSSC with the PFII-F membrane shows a larger open-circuit voltage (VOC), comparable short-circuit current density (JSC), better power conversion efficiency (η) of 9.26%, and superior long-term stability (up to 97% of its initial η) over 1500 h compared to the cell with standard liquid electrolyte (8.63%).

Viologens, or 1,1′-disubstituted-4,4′-bipyridiniums, are electrochromic materials with dramatic color change when reduced from transparent dication to colored radical cation. Many applications based on viologens have been developed, including anti-glare mirrors or displays in which viologens could be used to offer optical contrast. Additionally, by substituting different groups on bipyridiniums, the optical characteristics of viologens upon reduction could be tuned, such as alkyl for blue or aryl for green, which expands the versatility of viologens for displays. In an electrochromic device, viologens could be classified into three types of electrochromes depending on the environment or mechanism: type-1 for viologens in non-aqueous solvents, type-2 for precipitated viologens at radical cation state, and type-3 for immobilized viologens. Among them, type-3 viologen electrochromes are most known for their stability improved by immobilizing viologens, and therefore they were widely adopted in commercial electrochromic devices. The immobilization of viologens could be achieved by either anchoring viologens on substrates by direct bonding, polymerizing viologens, or introducing gel or solid-state electrolytes.

A novel polymer, denoted as TP-X, is synthesized by grafting 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl (4-amino-TEMPO) onto the poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) backbone. TP-X was electrospun into a nanofibrous polymer matrix and introduced into viologen-based electrochromic devices (ECDs). Heptyl viologen (HV) was chosen as the electrochromic material and TEMPO was added as the stable redox couple in the ECDs in this study. The results show that the addition of TP-X nanofibers (TP-X NF) effectively reduced the aggregation of HV and the grafted TEMPO moieties provide the extended surface area for electron transfer. The reduction in viologen aggregation led to outstanding stability and the extended electron transfer surface area resulted in fast write-erase response for ECDs with TP-X NF polymer matrix. The optimized ECD containing the TP-10 NF showed fast write-erase response times of 2.3 and 1.5 s for bleaching and coloring at 605 nm, respectively. More importantly, the incorporation of TP-10 NF gave improved stability of the ECDs, which retained more than 83% of its initial transmittance change at 605 nm after 10,000 operation cycles, as compared to the conventional solution-type ECD (27.3%). This study provides a potential polymer matrix to be utilized in various electrochemical applications for pursuing decent performance and reliable stability.

In this paper, a belief propagation (BP) decoding algorithm with early termination is proposed for polar code. The early termination is accomplished using the syndrome generated by the parity-check matrix, which can be transferred from the generator matrix. With the assistance of the early termination, the BP decoder can provide not only a better bit error rate performance but also significantly reduce the decoding complexity. For (1024, 512) polar codes, the average numbers of iterations can be reduced from 80 to 23 when Eb/N0=3 dB. The reduction in the computation complexity is about 70%.

Poly(hydroxymethyl 3,4-ethylenedioxythiophene) (PhmEDOT) and Poly(3,4- ethylenedioxythiophene) (PEDOT) thin films are prepared by electropolymerization method on indium tin oxide conducting glass in this study. Surface morphology of the thin films is observed using a scanning electron microscopy. Electrochemical and electrochromic properties including redox behaviors, UV–Vis absorbance spectra at different applying potentials, coloring/bleaching response times and transmittance modulation ability of the thin films are investigated. Photoelectrochromic devices (PECDs) composed of the PhmEDOT or the PEDOT thin films and dye-sensitized TiO2 photoanodes were assembled, and their photoelectrochromic performances compared. According to the obtained results, the PECD using the PhmEDOT thin film has faster photoelectrochromic coloring/bleaching rates and better transmittance modulation ability than the one using the PEDOT thin film.

A novel hybrid type electrochromic device (ECD) was fabricated, using a stable radical provider, 2,2,6,6−tetramethyl−1−piperidinyloxy (TEMPO) and two electrochromic (EC) materials, polyaniline (PANI) and heptyl viologen (HV(BF4)2). The PANI thin film and HV(BF4)2 solution were chosen as anodically and cathodically coloring materials, respectively. The TEMPO was selected to act as the anion storage species in pair with either of the electrochromic material. This type of assembly thus formed two electrochromic systems in one device, i.e., TEMPO−HV and TEMPO−PANI. The electrolyte for the ECD was composed of 0.1 M TEMPO, 0.05 M HV(BF4)2, 0.1 M TBABF4, and 1.0 mM HClO4 in propylene carbonate (PC), and was placed in between two ITO glasses. By varying the operating voltage between 0 and 1.5 V, the TEMPO−HV system showed a transmittance change (ΔT) of 46.2% at 550 nm. By varying the operating voltage between 0 and −1.0 V, the TEMPO−PANI system showed a ΔT of 45.5% at 700 nm. The complete system activation (both TEMPO−HV and TEMPO−PANI) was achieved by setting the operating voltage between −1.0 and 1.5 V, obtaining a ΔT of 53.3% at 550 nm. The estimated switching times for the total system were 3.1 and 3.4 s for bleaching and darkening, respectively. The coloration efficiencies of the ECD at 700 and 500 nm, for the green to blue transition, were 159.7 and 169.2 cm2C-1, respectively, while 88.8 and 23.5 cm2C-1 for the transparent to green transition. The proposed hybrid ECD was characterized by cyclic voltammetry (CV), UV–Vis absorbance spectra, dynamic transmittance curves, and long-term stability test.

Herein, three kinds of viologens-based electrochromic devices (ECDs) (heptyl viologen (HV(BF4)2), octyl viologen (OV(BF4)2), and nonyl viologen (NV(BF4)2)) were fabricated utilizing ferrocene (Fc) as a redox mediator. Among them, the NV(BF4)2-based ECD exhibits the highest coloration efficiency (36.2 cm2/C) owing to the lowest driving energy. Besides, switching between 0 and 1.2 V, the NV(BF4)2-based ECD shows a desirable initial transmittance change (ΔT = 56.7% at 605 nm), and long-term stability (ΔT = 45.4% after 4000 cycles). Furthermore, a UV-cured polymer electrolyte containing polymeric ionic liquid (PIL, 1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) and ethoxylated trimethylolpropane triacrylate (ETPTA) was introduced to the NV(BF4)2-based ECD. By controlling the weight percentage of the PIL, different curing degrees of the polymer electrolytes were obtained and led to an improved stability of the NV(BF4)2-based ECD because of the immobilization of NV(BF4)2. This observation was explained by calculating the apparent diffusivity (Dapp) of the redox species in the NV(BF4)2-based ECD under various curing degrees. In addition, increasing the amount of PIL leads to a lower driven energy needed for the NV(BF4)2-based ECD, following the same trend as the value of Dapp. Among all NV(BF4)2-based ECDs, 20 wt % of PIL addition (20-PIL ECD) exhibits large transmittance change (ΔT = 55.2% at 605 nm), short switching times (2.13 s in coloring and 2.10 s in bleaching), high coloration efficiency (60.4 and 273.5 cm2/C at 605 nm, after excluding the current density at the steady state), and exceptional cycling stability (ΔT = 53.8% after 10,000 cycles, or retained 97.5% of its initial ΔT).