理學院

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學院概況

理學院設有數學系、物理學系、化學系、生命科學系、地球科學系、資訊工程學系6個系(均含學士、碩士及博士課程),及科學教育研究所、環境教育研究所、光電科技研究所及海洋環境科技就所4個獨立研究所,另設有生物多樣性國際研究生博士學位學程。全學院專任教師約180人,陣容十分堅強,無論師資、學術長現、社會貢獻與影響力均居全國之首。

特色

理學院位在國立臺灣師範大學分部校區內,座落於臺北市公館,佔地約10公頃,是個小而美的校園,內含國際會議廳、圖書館、實驗室、天文臺等完善設施。

理學院創院已逾六十年,在此堅固基礎上,理學院不僅在基礎科學上有豐碩的表現,更在臺灣許多研究中獨占鰲頭,曾孕育出五位中研院院士。近年來,更致力於跨領域研究,並在應用科技上加強與業界合作,院內教師每年均取得多項專利,所開發之商品廣泛應用於醫、藥、化妝品、食品加工業、農業、環保、資訊、教育產業及日常生活中。

在科學教育研究上,臺灣師大理學院之排名更高居世界第一,此外更有獨步全臺的科學教育中心,該中心就中學科學課程、科學教與學等方面從事研究與推廣服務;是全國人力最充足,設備最完善,具有良好服務品質的中心。

在理學院紮實、多元的研究基礎下,學生可依其性向、興趣做出寬廣之選擇,無論對其未來進入學術研究領域、教育界或工業界工作,均是絕佳選擇。

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Now showing 1 - 10 of 15
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    Enhanced performance of photodetector and photovoltaic based on carrier reflector and back surface field generated by doped graphene
    (American Institute of Physics (AIP), 2012-08-13) C.-W. Chang; D.-Y. Wang; W.-C. Tan; I-S. Huang; I-S. Wang; Chia-Chun Chen; Y.-J. Yang; Y.-F. Chen
    We report the influence of carrier reflector and back surface field generated by dopedgraphene on n-ZnO nanoridges/p-silicon photodetectors and silicon solar cells. It is found that the p-type graphene not only acts as an electron blocking layer, but also helps the collection of photogenerated holes. Quite surprisingly, the on/off ratio of the photodetector with the insertion of dopedgraphene can be increased by up to 40 times. Moreover, we demonstrate that typical silicon solar cells with the dopedgraphene, the cell efficiency can be enhanced by about 20%. Our approach would expand numerous applications for graphene-based optoelectronic devices.
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    FeS2 Nanocrystal Ink as a Catalytic Electrode for Dye-Sensitized Solar Cells
    (Wiley-VCH Verlag, 2013-06-24) Y.-C. Wang; D.-Y. Wang; Y.-T. Jiang; H.-A. Chen; Chia-Chun Chen; K.-C. Ho; - H.-L. Chou; Chun-Wei Chen
    Calligraphic counter electrodes: An important photovoltaic application using FeS2 nanocrystal (NC) pyrite ink to fabricate a counter electrode as an alternative to Pt in dye-sensitized solar cells is demonstrated. FeS2 NC ink exhibits excellent electrochemical catalytic activity and remarkable electrochemical stability. ITO=indium-doped tin oxide.
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    Low operation voltage macromolecular composite memory assisted by graphene nanoflakes
    (Royal Society of Chemistry, 2013-01-21) Y.-C. Lai; D.-Y. Wang; I-S. Huang; Y.-T. Chen; Y.-H. Hsu; T.-Y. Lin; H.-F. Meng; T.-C. Chang; Y.-J. Yang; Chia-Chun Chen; F.-C. Hsu; Y.-F. Chen
    The trend towards simple and low-cost processing is one of the most important for macromolecular memory development. Here, bistable memory devices using a solution-processable active material, a mixture of graphene nanoflakes (GNFs) and insulating poly(vinyl alcohol) (PVA), are investigated, which serve as the first example for the direct integration of as-prepared nanoscale graphene into macromolecular memory devices through a one-step low-temperature processing method. Bistable electrical switching behavior and nonvolatile rewritable memory effects are realized by using an indium–tin-oxide/GNF–PVA/silver (ITO/GNF–PVA/Ag) sandwich structure. The resulting device exhibits low operation voltages of +1.4 V (turn-on) and −1.3 V (turn-off), which is promising for memory cells with low power consumptions. The programmable ON- and OFF-states possess a retention time of over 104 s and endure up to 107 read pulses. The carrier transport in the OFF- and ON-states follows the typical trap-limited space charge limited current and Ohmic laws, respectively. The asymmetric electrical switch behavior is therefore attributed to conducting filaments formed in the PVA layer assisted by the charged GNFs that induce the transition of the conductivity. Our study provides a potential approach for integrating as-prepared graphene into macromolecular memory devices with excellent performances through a simple solution-process.
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    Enhanced charge extraction in inverted hybrid photovoltaic cells assisted by graphene nanoflakes
    (Royal Society of Chemistry, 2011-11-21) Y.-M. Sung; F.-C. Hsu; D.-Y. Wang; I.-S. Wang; Chia-Chun Chen; H.-C. Liao; W.-F. Su; Y.-F. Chen
    We use graphene nanoflakes (GNFs) to greatly enhance the charge extraction out of a photoactive blend in inverted hybrid poly(3-hexylthiophene):(6,6)-phenyl C61butyric acid methyl ester (P3HT:PCBM)/ZnO-nanorod photovoltaic cells. Instead of a continuous film, solution processed GNFs with dimensions less than 200 nm � 200 nm are homogeneously scattered on top of the well-aligned ZnO-nanorods. Those GNFs play key roles, they serve as an electron drain to collect electron flow out to ZnO-nanorods, enhance the carrier mobility of the device and promote holes to drift toward the surface in contact with the cathode. As a result, there is a large enhancement in photocurrent and photovoltage of 35% and 27%, respectively, leading to an improved cell efficiency by up to about 100%.
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    Solution-Processable Pyrite FeS2 Nanocrystals for the Fabrication of Heterojunction Photodiodes with Visible to NIR Photodetection
    (Wiley-VCH Verlag, 2012-07-03) D.-Y. Wang; Y.-T. Jiang; C.-C. Lin; S.-S. Li; Y.T. Wang; Chia-Chun Chen; C.-W. Chen
    A heterojunction photodiode with NIR photoresponse using solution processable pyrite FeS2 nanocrystal ink is demonstrated which has the advantages of earth-abundance and non-toxicity. The device consists of a FeS2 nanocrystal (NC) thin film sandwiched with semiconducting metal oxides with a structure of ITO/ZnO/FeS2 NC/MoO3/Au, which exhibits an excellent photoresponse with a spectral response extended to NIR wavelengths of up to 1150 nm and a high photocurrent/dark current ratio of up to 8000 at -1 V under AM1.5 illumination (100 mW cm−2).
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    Type-II heterojunction organic/inorganic hybrid non-volatile memory based on FeS(2) nanocrystals embedded in poly(3-hexylthiophene)
    (IOP Publishing, 2011-07-27) C.-W. Lin; D.-Y. Wang; Y. Tai; Y.-T. Jiang; M.-C. Chen; Chia-Chun Chen; Y.-J. Yang; Y.-F. Chen
    Electrical bistable behaviour was demonstrated in memory devices based on n-type FeS2 nanocrystals (NCs) embedded in a p-type poly(3-hexylthiophene) (P3HT) matrix. An organic/inorganic hybrid non-volatile memory device with a type-II band alignment, fabricated by a spin-coating process, exhibited electrical bistable characteristics. The bistable behaviour of carrier transport can be well described through the space-charge-limited current model. The small amount of FeS2 NCs in this device serve as an excellent charge trapping medium arising from the type-II band alignment between FeS2 and P3HT. Our study suggests a new way to integrate non-volatile memory with other devices such as transistor or photovoltaic since the presented FeS2/P3HT offers a type-II band alignment.
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    Enhanced Infrared Light Harvesting of Inorganic Nanocrystal Photovoltaic and Photodetector on Graphene Electrode
    (American Institute of Physics, 2011-06-27) C.-C. Lin; D.-Y. Wang; K.-H. Tu; Y.-T. Jiang; M.-H. Hsieh; Chia-Chun Chen; C.-W. Chen
    We demonstrate an enhancement of infrared light harvesting of inorganic PbSnanocrystalphotovoltaic and photodetectordevices based on the transparent grapheneelectrode. Due to high infrared transparency of the grapheneelectrode with respect to indium tin oxide (ITO), the infrared photoresponse of the graphene-based device is superior to the ITO-based counterpart, in spite of a higher sheet resistance of the grapheneelectrode. The outstanding infrared characteristics of the devices based on the grapheneelectrode make it a promising candidate for infrared optoelectronic applications such as solar cells, imaging and sensing, or optical communication.
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    Simple Replacement Reaction for the Preparation of Ternary Fe1?xPtRux Nanocrystals with Superior Catalytic Activity in Methanol Oxidation Reaction.
    (American Chemical Society, 2012-06-20) D.-Y. Wang; H.-L. Chou; Y.-C. Lin; F.-J. Lai; C.-H. Chen; J.-F. Lee; B.-J. Hwang; Chia-Chun Chen
    The finding of new metal alloyed nanocrystals (NCs) with high catalytic activity and low cost to replace PtRu NCs is a critical step toward the commercialization of fuel cells. In this work, a simple cation replacement reaction was utilized to synthesize a new type of ternary Fe1–xPtRux NCs from binary FePt NCs. The detailed structural transformation from binary FePt NCs to ternary Fe1–xPtRux NCs was analyzed by X-ray absorption spectroscopy (XAS). Ternary Fe35Pt40Ru25, Fe31Pt40Ru29, and Fe17Pt40Ru43 NCs exhibit superior catalytic ability to withstand CO poisoning in methanol oxidation reaction (MOR) than do binary NCs (FePt and J-M PtRu). Also, the Fe31Pt40Ru29 NCs had the highest alloying extent and the lowest onset potential among the ternary NCs. Furthermore, the origin for the superior CO resistance of ternary Fe1–xPtRux NCs was investigated by determining the adsorption energy of CO on the NCs’ surfaces and the charge transfer from Fe/Ru to Pt using a simulation based on density functional theory. The simulation results suggested that by introducing a new metal into binary PtRu/PtFe NCs, the anti-CO poisoning ability of ternary Fe1–xPtRux NCs was greatly enhanced because the bonding of CO–Pt on the NCs’ surface was weakened. Overall, our experimental and simulation results have indicated a simple route for the discovery of new metal alloyed catalysts with superior anti-CO poisoning ability and low usage of Pt and Ru for fuel cell applications.
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    Quantum Dot Light-Emitting Diode Using Solution-Processable Graphene Oxide as the Anode Interfacial Layer.
    (American Chemical Society, 2012-05-10) D.-Y. Wang; I.-S. Wang; I.-S. Huang; Y.-C. Yeh; S.-S. Li; K.-H. Tu; Chia-Chun Chen; C.-W. Chen
    In this article, the solution processable graphene oxide (GO) thin film was utilized as the anode interfacial layer in quantum dot light emitting diodes (QD-LEDs). The QD-LED devices (ITO/GO/QDs/TPBi/LiF/Al) were fabricated by employing a layer-by-layer assembled deposition technique with the electrostatic interaction between GO and QDs. The thicknesses of GO thin films and the layer number of CdSe/ZnS QD emissive layers were carefully controlled by spin-casting processes. The GO thin films, which act as the electron blocking and hole transporting layer in the QD-LED devices, have demonstrated the advantage of being compatible with fully solution-processed fabrications of large-area printable optoelectronic devices.
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    Efficient Light Harvesting by Photon Downconversion and Light Trapping in Hybrid ZnS Nanoparticles/Si Nanotips Solar Cells
    (American Chemical Society, 2010-10-26) C.-Y. Huang; D.-Y. Wang; C.-H. Wang; Y.-T. Chen; Y.-T. Wang; Y.-T. Jiang; Y.-J. Yang; Chia-Chun Chen; Y.-F. Chen
    A hybrid colloidal ZnS nanoparticles/Si nanotips p−n active layer has been demonstrated to have promising potential for efficient solar spectrum utilization in crystalline silicon-based solar cells. The hybrid solar cell shows an enhancement of 20% in the short-circuit current and approximately 10% in power conversion efficiency compared to its counterpart without integrating ZnS nanoparticles. The enhancement has been investigated by external quantum efficiency, photoluminescence excitation spectrum, photoluminescence, and reflectance to distinct the role of ZnS quantum dots for light harvesting. It is concluded that ZnS nanoparticles not only act as frequency downconversion centers in the ultraviolet region but also serve as antireflection coating for light trapping in the measured spectral regime. Our approach is ready to be extended to many other material systems for the creation of highly efficient photovoltaic devices.