Browsing by Author "Huang, Tzu-Yen"

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2-Alkyl-5-thienyl-Substituted Benzo[1,2-b:4,5-b ']dithiophene-Based Donor Molecules for Solution-Processed Organic Solar Cells
(2013-10-09)
Patra, Dhananjaya
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Huang, Tzu-Yen
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Chiang, Chao-Cheng
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Maturana, Ramon Orlando Valencia
;
Pao, Chun-Wei
In this study, we have strategically designed and convergently synthesized two novel, symmetrical, and linear A-D-A-type pi-conjugated donor molecules (TBDTCNR, TBDTCN), each containing a planar electron-rich 2-octylthiene-5-yl-substituted benzodithiophene (TBDT) unit as the core, flanked by octylthiophene units and end-capped with electron-deficient cyanoacetate (CNR) or dicyanovinyl (CN) units. We thoroughly characterized both of these materials and investigated the effects of the end groups (CNR, CN) on their optical, electrochemical, morphological, and photovoltaic properties. We then fabricated solution-processed bulk heterojunction organic solar cells incorporating TBDTCNR and TBDTCN. Among our tested devices, the one containing TBDTCNR and [6,6]-phenyl-C-61-butyric acid methyl ester in a 1:0.40 ratio (w/w) exhibited the highest power conversion efficiency (5.42%) with a short-circuit current density (J(sc)) of 9.08 mA cm(-2), an open circuit voltage (V-oc) of 0.90 V, and an impressive fill factor (FF) of 0.66 under AM 1.5G irradiation (100 mW cm(-2)). The FFs of these solution-processed small-molecule organic solar cells (SMOSCs) are outstanding when compared with those recently reported for benzodithiophene (BDT)-based SMOSCs, because of the high crystallinity and excellent stacking properties of the TBDT-based compounds.
2.5 dB sensitivity improvement by optimizing the driving voltage of an MZM and electrical filter bandwidth of optical duobinary transmission systems
(2006)
Lu, Yu-Chang
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Wei, Chia-Chien
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Chen, Jason (Jyehong)
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Tsao, Cheng
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Chi, Sien
We numerically and experimentally demonstrated that 100% driving voltage doesn't necessarily yield optimal results in duobinary systems. Compared with conventional condition, a 2.5 dB sensitivity improvement is obtained using 3 GHz LPFs with optimum voltage. (C) 2006 Optical Society of America.
A high performance electrochemical sensor for acetaminophen based on a rGO-PEDOT nanotube composite modified electrode
(2014)
Huang, Tzu-Yen
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Kung, Chung-Wei
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Wei, Hung-Yu
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Boopathi, Karunakara Moorthy
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Chu, Chih-Wei
In this study, we perform an electrochemical sensing using a conductive composite film containing reduced graphene oxide (rGO) and poly(3,4-ethylenedioxythiophene) nanotubes (PEDOT NTs) as an electrode modifier on a glassy carbon electrode (GCE). Scanning electron microscopy suggests that the rGO covers the surface of GCE uniformly and the PEDOT NTs act as a conducting bridge to connect the isolated rGO sheets. By combining these two materials, the conductivity and the surface coverage of the film can be enhanced, which is beneficial for electrochemical sensing. The rGO-PEDOT NT composite modified electrode is applied for an effective sensor to analyze acetaminophen. The obtained electrochemical activity is much higher than those obtained by the rGO-and PEDOT NT-modified electrodes; the higher electrochemical activity may be attributed to the higher conductivity and greater coverage of the rGO-PEDOT NT composite film on the GCE. Furthermore, interference tests indicate that the rGO-PEDOT NT composite modified electrode exhibits high selectivity toward the analyte. This novel method for combining the rGO and PEDOT NTs establishes a new class of carbon material-based electrodes for electrochemical sensors.
Enhanced Organic Solar Cell Performance by Lateral Side Chain Engineering on Benzodithiophene-Based Small Molecules
(2018-08-01)
Patra, Dhananjaya
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Budiawan, Widhya
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Huang, Tzu-Yen
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Wei, Kung-Hwa
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Wang, Pen-Cheng
The three novel acceptor-donor-acceptor (A-D-A) conjugated small molecules were synthesized, each featuring a benzodithiophene (BDT) core presenting lateral flexible side chains: TB-BDT6T substituted with 2-ethynyl-5-octylthiophene, TS-BDT6T substituted with 2-(octylthio)-thiophene, and TT-BDT6T substituted with 2-(2-ethylhexyl)-thieno[3,2-b]thiophene groups. The lateral incorporation of functionalized pi-conjugated flexible side chains, without altering the end-capped acceptor (cyanoacetate) moieties, amended the optoelectronic properties of these BDT-based small molecules. X-ray diffraction spectroscopy revealed that these small molecules possess high crystallinity; moreover, the optimized blend film morphologies, recorded using atomic force microscopy, revealed miscibility with PC61BM, and turn out nanoscale phase separations. The energy levels of the highest occupied and lowest unoccupied molecular orbitals of these small molecules were allowed, leading to high open-circuit voltages (V-oc) for their solar cell devices. The bulk heterojunction small-molecule solar cell based on TT-BDT6T:PC61BM blend presented the highest power conversion efficiency (5.80%) with a high value of V-oc of 0.98 V, a short circuit density of 9.49 mA cm(-2), and a fill factor of 62.44% under AM 1.5G irradiation (100 mW cm(-2)).
Peculiar anatomic variation of recurrent laryngeal nerve and EMG change in a patient with right substernal goiter and pre-operative vocal cord palsy-case report
(2020-06-01)
Wang, Jia Joanna
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Lu, I-Cheng
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Chang, Pi-Ying
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Wu, Che-Wei
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Wang, Ling-Feng
We report a patient with right substernal goiter and preoperative vocal cord palsy (VCP). During dissection, an anatomic variation of the recurrent laryngeal nerve (RLN) and a prolonged EMG were detected by intraoperative neuromonitoring (IONM). Symmetrical vocal cord movement was recorded one month after surgery. The potential for recovery of vocal cord function is high after surgical treatment of a thyroid tumor with preoperative VCP. An IONM enables early localization of the RLN position. lb the best of our knowledge, this case of prolonged EMG in an abnormal acquired-ventral RLN trajectory is the first reported in the literature.
Quantitative Characterization and Mechanism of Formation of Multilength-scale Bulk Heterojunction Structures in Highly Efficient Solution-Processed Small-Molecule Organic Solar Cells
(2015-07-23)
Huang, Yu-Ching
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Tsao, Cheng-Si
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Huang, Tzu-Yen
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Cha, Hou-Chin
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Patra, Dhananjaya
In this study we used simultaneous grazing-incidence small- and wide-angle X-ray scattering (GISAXS and GIWAXS, respectively) to probe the multilength-scale structures of thin active layers comprising the linear A-D-A-type pi-conjugated donor molecule TBDTCNR and the fullerene acceptor molecule PC61BM for use in solution-processed small-molecule-based organic solar cells (SMOSCs). We found that the pseudo-two-dimensional fractal-like networks in the bulk heterojunction (BHJ) structure were determined by mutual interactions between the small-molecule (SM) crystallites and the nanoscale PC61BM clusters during their formation and phase separation, and deduced quantitatively, at multiple length scales, the BHJ structures comprising these SM crystallites and PC61BM clusters. We also conducted in situ GIWAXS measurements to study the temporal behavior and kinetics of SM crystallization from solution to the solid film state. Our GISAXS/GIWAXS study revealed that the multilength-scale BHJ structures in the thin films could be tuned effectively by varying the amount of incorporated PC61BM and the annealing temperature. This study provides fundamental information relating to the mechanism of formation of hierarchical BHJ structures through relatively rapid crystallization of a highly crystalline SM, as well as the relationships among the hierarchical structure, the photovoltaic performance, and the mechanism of formation, thereby allowing greater control over BHJ structures in SMOSCs with optimized fabrication and performance.
rGO/SWCNT composites as novel electrode materials for electrochemical biosensing
(2013-05-15)
Huang, Tzu-Yen
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Huang, Jen-Hsien
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Wei, Hung-Yu
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Ho, Kuo-Chuan
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Chu, Chih-Wei
In this study we performed electrochemical sensing using conductive carbon composite films containing reduced graphene oxide (rGO) and single-walled carbon nanotubes (SWCNTs) as electrode modifiers on glassy carbon electrodes (GCEs). Raman spectroscopy, transmission electron microscopy, atomic force microscopy, and scanning electron microscopy all suggested that the rGO acted as a surfactant, covering and smoothing out the surface, and that the SWCNTs acted as a conducting bridge to connect the isolated rGO sheets, thereby (i) minimizing the barrier for charge transfer between the rGO sheets and (ii) increasing the conductivity of the film. We used the rGO/SWCNT-modified GCE as a sensor to analyze hydrogen peroxide (H2O2) and beta-nicotinamide adenine dinucleotide (NADH), obtaining substantial improvements in electrochemical reactivity and detection limits relative to those obtained from rGO- and SWCNT-modified electrodes, presumably because of the higher conductivity and greater coverage on the GCE, due to pi-pi interactions originating from the graphitic structures of the rGO and SWCNTs. The electrocatalysis response was measured by cyclic voltammetry and amperometric current-time (i-t) curve techniques. The linear concentration range of H2O2 and NADH detection at rGO/SWCNT-modified electrode is 0.5-5 M and 20-400 mu M. The sensitivity for H2O2 and NADH detection is 2732.4 and 204 mu A mM(-1) cm(-2), and the limit of detection is 1.3 and 0.078 mu M respectively. Furthermore, interference tests indicated that the carbon composite film exhibited high selectivity toward H2O2 and NADH. Using GO as a solubilizing agent for SWCNTs establishes a new class of carbon electrodes for electrochemical sensors. (C) 2012 Elsevier B.V. All rights reserved.
Safety of Ligasure exact dissector in thyroidectomy with continuous neuromonitoring: a porcine model
(2020-06-01)
Huang, Tzu-Yen
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Lin, Yi-Chu
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Tseng, Hsin-Yi
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Dionigi, Gianlorenzo
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Kim, Hoon-Yub
Background: The purpose of this study was to investigate and define safety parameters for using the Ligasure exact dissector (LED) for dissection close to the recurrent laryngeal nerve (RLN) during thyroidectomy. Methods: Real-time electrophysiologic electromyographic (EMG) tracings were recorded in 16 RLNs (8 piglets) during various applications of LED under continuous intraoperative monitoring in this prospective porcine model study. In the activation study, LED was activated at varying distances from the RLN. In the cooling study, LED was activated with different cooling times or after touching the sternodeidomastoid muscle before application to the RLN. Results: In the activation study, no adverse EMG events occurred at distances longer than I rum. In the cooling study, no adverse EMG events occurred after a 2-second cooling time. Additionally, no adverse EMG events occurred when a sternodeidomastoid muscle touch maneuver was used for cooling. Conclusions: The LED can be safely used at distance of 1 mm or longer, and it should be cooled for at least 2 seconds or by muscle touch maneuver. Thyroid surgeons can avoid RLN injury if standard procedures for LED use are observed.
Safety parameters of ferromagnetic device during thyroid surgery: Porcine model using continuous neuromonitoring
(1970-01-01)
Huang, Tzu-Yen
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Lin, Yi-Chu
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Tseng, Hsin-Yi
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Dionigi, Gianlorenzo
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Kim, Hoon Yub
Background The ferromagnetic (FM) device is a new surgical energy modality. This study investigated dynamic recurrent laryngeal nerve (RLN) electromyographic (EMG) data to define safety parameters for using FM devices in thyroidectomy. Methods Real-time EMG tracings obtained under continuous neuromonitoring were recorded from 24 RLNs (12 piglets). In the activation study, FM devices were activated at varying distances from the RLN. In the cooling study, FM devices were cooled for varying time intervals, or muscle touch maneuver was performed, before contact with the RLN. Results During the FMwand/FMsealer activation, no adverse EMG events occurred at distances of 2 mm or longer. The cooling study revealed no adverse EMG events after 1-second (FMwand) or 3-second (FMsealer) intervals or after muscle touch maneuver. Conclusions An FM device should be activated at a distance of 2 mm from the RLN and should be adequately cooled before further contact with the RLN. Surgeons can avoid RLN injury by observing standard procedures for using FM devices.
Study on Oxidation State Dependent Electrocatalytic Ability for I-/I-3(-) Redox Reaction of Reduced Graphene Oxides
(2014-01-01)
Yeh, Min-Hsin
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Lin, Lu-Yin
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Huang, Tzu-Yen
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Chuang, Hui-Min
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Chu, Chih-Wei
The influence of oxidation states on electrocatalytic abilities for I-3(-) reduction is discussed for reduced graphene oxide (rGO), which is a promising catalyst of counter electrodes for dye-sensitized solar cells (DSSCs). The oxidation states of rGO can be controlled via a photothermal reduction process by varying exposure times. The results reveal that the rGO with lower oxidation state shows smaller charge transfer resistance at the electrode/electrolyte interface and better electrocatalytic ability attributed to higher standard heterogeneous rate constant (k(0)) and reasonable electrochemical surface area (A(e)) for I-3(-) reduction, both are quantitatively determined by a rotating disk electrode system using the Koutecky-Levich equation.
U-shaped strap muscle flap for difficult thyroid surgery
(2020-04-01)
Ko, How-Yun
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Lu, I-Cheng
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Chang, Pi-Ying
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Wang, Ling-Feng
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Wu, Che-Wei
Background: Open thyroidectomy via conventional midline approach can be challenging in complex thyroid surgeries. This study proposes a U-shaped strap muscle flap (USMF) technique that provides adequately wide exposure of the surgical field. Methods: Strap muscles were cut close to the clavicle and along the anterior margin of both sternocleidomastoid muscles followed by total thyroidectomy in 20 patients as USMF group, and surgical outcomes were compared with 40 patients who had received total thyroidectomy via midline approach. Results: No patient had postoperative hematoma, vocal cord paralysis, permanent hypocalcaemia, wound infection or flap necrosis. At 2 months post-surgery, objective voice analysis and subjective assessment of voice and swallowing showed no significant difference between groups. Conclusions: USMF provides superb surgical field exposure, and the voice and swallowing functions after USMF are comparable to those obtained by midline approach. The USMF approach is a feasible option for selective difficult thyroid surgery.
Wet-milled transition metal oxide nanoparticles as buffer layers for bulk heterojunction solar cells
(2012)
Huang, Jen-Hsien
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Huang, Tzu-Yen
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Wei, Hung-Yu
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Ho, Kuo-Chuan
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Chu, Chih-Wei
"In this study, we used high-energy grinding to prepare solutions of well-dispersed transition metal oxides (TMOs), allowing the fabrication of crystalline TMO films with high surface coverage through solution processing without post-annealing. Moreover, because this solution-based method did not require surfactants, it preserved the intrinsic electronic and optical properties of the TMOs. The resulting smooth, continuous, and highly transparent TMO films were readily integrated into organic solar cells. After incorporating MoO3 thin films into bulk heterojunction solar cells, we obtained devices delivering power conversion efficiencies of up to 3.68%, rivalling those of devices fabricated with commercial poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) as the hole collection layer."