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 21
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    Low-Frequency Contact Noise of GaN Nanowire Device Detected by Cross-Spectrum Technique.
    (Japan Society of Applied Physics, 2011-06-01) L.-C. Li; K.-H. Huang; J.-A. Wei; Y.-W. Suen; T.-W. Liu; Chia-Chun Chen; L.-C. Chen; K.-H. Chen
    We report the properties of low-frequency contact noise of multielectrode GaN nanowire (NW) devices. A two-port cross-spectrum technique is used to discriminate the noise of the ohmic contact from that of the NW section. The diameter of the GaN NW is around 100 nm. The Ti/Al electrodes of the NWs are defined by e-beam lithography. The typical resistance of a NW section with a length of 800 nm is about 5.5 kΩ and the two-wire resistance is below 100 kΩ. The results show that the low-frequency excess noise of the GaN NW is much smaller than that of the current-flowing contact, indicating that the contact noise dominates the noise behavior in our GaN NW devices. A careful study of the noise amplitude (A) of the 1/f noise of different types of NW and carbon nanotube devices, both in our work and in the literature, yields an empirical formula for estimating A from the two-wire resistance of the device.
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    Vitalizing fuel cells with vitamins: pyrolyzed vitamin B12 as a non-precious catalyst for enhanced oxygen reduction reaction of polymer electrolyte fuel cells
    (Royal Society of Chemistry, 2012-01-01) S.-T. Chang; C.-H. Wang; H.-Y. Du; H.-C.Hsu; C.-M. Kang; Chia-Chun Chen; J.C.-S. Wu; S.-C. Yen; W.-F. Huang; L.-C. Chen; M.-C. Lin; K.-H. Chen
    The limited natural abundance and high cost of Pt has been a major barrier in its applications for hydrogen or methanol fuel cells. In this work, based on the pyrolyzed corrin structure of vitamin B12 (py-B12/C), it is reported to produce superior catalytic activity in the oxygen reduction reaction (ORR) with an electron transfer number of 3.90, which is very close to the ideal case of 4. The H2–O2fuel cell using py-B12/C provides a maximum power density of 370 mW cm−2 and a current density of 0.720 A cm−2 at 0.5 V at 70 °C. Calculations based on density functional theory suggests that the corrin complex with a low-symmetric structure offers a much preferable path for the ORR, which is not applicable to the porphyrin with a high-symmetric structure. The long-term stability and high ORR activity of py-B12/C make it a viable candidate as a Pt-substitute in the ORR.
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    Flexible supercapacitor based on polyaniline nanowires/carbon cloth with both high gravimetric and area-normalized capacitance
    (Elsevier, 2010-07-01) Y.-Y. Horng; Y.-C. Lu; Y.-K. Hsu; Chia-Chun Chen; L.-C. Chen; K.-H. Chen
    Flexible supercapacitor is successfully fabricated using polyaniline nanowires/carbon cloth (PANI-NWs/CC) nanocomposite. High gravimetric capacitance of 1079 F g−1 at a specific energy of 100.9 Wh kg−1 and a specific power of 12.1 kW kg−1 is obtained. Moreover, this approach also offers an exceptionally high area-normalized capacitance of 1.8 F cm−2. The diffusion length of protons within the PANI-NWs is estimated to be about 60 nm by electrochemical impedance analysis, which indicates that the electrochemical performance of the electrode is not limited by the thickness of PANI-NWs. The electrochemical performance of PANI-NWS/CC remains without any deterioration, even when the cell is bent under high curvature. These results clearly present a cost-effective and simple method of fabrication of the nanostructured polymers with enormous potential in flexible energy storage device applications.
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    Low methanol-permeable polyaniline/Nafion composite membrane for direct methanol fuel cells
    (Elsevier, 2009-05-15) C.-H. Wang; Chia-Chun Chen; H.-C. Hsu; H.-Y. Du; C.-R. Chen; J.-Y. Hwang; L.-C. Chen; H.-C. Shih; J. Stejskal; K.-H. Chen
    Protonated polyaniline (PANI) is directly polymerized on Nafion 117 (N117), forming a composite membrane, to act as a methanol-blocking layer to reduce the methanol crossover in the direct methanol fuel cell (DMFC), which is beneficial for the DMFC operating at high methanol concentration. The PANI layer grown on the N117 with a thickness of 100 nm has an electrical conductivity of 13.2 S cm−1. The methanol permeability of the PANI/N117 membrane is reduced to 59% of that of the N117 alone, suggesting that the PANI/N117 can effectively reduce the methanol crossover in the DMFC. Comparison of membrane-electrode-assemblies (MEA) using the conventional N117 and the newly developed PANI/N117 composite shows that the PANI/N117-based MEA outputs higher power at high methanol concentration, while the output power of the N117-based MEA is reduced at high methanol concentration due to the methanol crossover. The maximum power density of the PANI/N117-based MEA at 60 °C is 70 mW cm−2 at 6 M methanol solution, which is double the N117-based MEA at the same methanol concentration. The resistance of PANI/N117 composite membrane is reduced at elevated methanol concentration, due to the hydrogen bonding between methanol and PANI pushes the polymer chains apart. It is concluded that the PANI/N117-based MEA performs well at elevated methanol concentration, which is suitable for the long-term operation of the DMFC.
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    On-chip Fabrication of Well-aligned and Contact-barrier-free GaN Nanobridge Devices with Ultrahigh Photocurrent Responsivity
    (Wiley-VCH Verlag, 2008-07-01) R.-S. Chen; S.-W. Wang; Z.-H. Lan; J. T.-H. Tsai; C.-T. Wu; L.-C. Chen; K.-H. Chen; Y.-S. Huang; Chia-Chun Chen
    Building nanobridges: Direct integration of an ensemble of GaN nanowires (n) onto a microchip produces a viable nanobridge (NB) device with good alignment and contact performance, the design of which demonstrates the potential of nanowires for sensor development. These GaN NBs have strong surface-enhanced photoconductivity with ultrahigh responsivity
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    Direct-growth of Polyaniline Nanowires for Enzyme-immobilization and Glucose Detection
    (Elsevier, 2009-04-01) Y.-Y. Horng; Y.-K. Hsu; A. Ganguly; Chia-Chun Chen; L.-C. Chen; K.-H. Chen
    Amperometric enzyme biosensor based on the glucose oxidase (GOx) incorporated polyaniline nanowires (PANI-NWs) on carbon cloth (CC) electrode was demonstrated. The simple, direct-growth of PANI-NWs on CC, via electrochemical polymerization, provides free-standing, template-independent, hence almost (interfacial) defects-free nanostructures. The defect-free interfaces, along with the excellently sensitive organic nanostructured-surface, as evident from its significantly large effective surface area (24 times the geometric area) for redox-sensing, allows efficient entrapment/immobilization and sensing of biomolecules, via rapid electron-transfer at NWs-CC. The GOx-immobilized PANI-NWs/CC, even in initial unoptimized stage, exhibited an excellent sensitivity, ∼2.5 mA mM−1 cm−2, to glucose, over detection range 0–8 mM, adequate for clinical monitoring of human glucose levels. The report clearly reveals a cost-effective simple system possessing enormous potentiality for biosensors, bioenergy and bioelectronics applications.
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    High-phase-purity zinc-blende InN on r-plane sapphire substrate with controlled nitridation pretreatment
    (American Institute of Physics (AIP), 2008-03-17) C.-L. Hsiao; T.-W. Liu; C.-T. Wu; H.-C. Hsu; G.-M. Hsu; L.-C. Chen; W.-Y. Shiao; C.-C. Yang; A. Gaellstroem; P.-O. Holtz; Chia-Chun Chen; K.-H. Chen
    High-phase-purity zinc-blende (zb) InN thin film has been grown by plasma-assisted molecular-beam epitaxy on r-plane sapphire substrate pretreated with nitridation. X-ray diffraction analysis shows that the phase of the InN films changes from wurtzite (w) InN to a mixture of w-InN and zb-InN, to zb-InN with increasing nitridation time. High-resolution transmission electron microscopy reveals an ultrathin crystallized interlayer produced by substrate nitridation, which plays an important role in controlling the InN phase. Photoluminescence emission of zb-InN measured at 20 K shows a peak at a very low energy, 0.636 eV, and an absorption edge at ∼0.62 eV is observed at 2 K, which is the lowest bandgap reported to date among the III-nitride semiconductors.
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    Enhanced Emission of (In, Ga) Nitride Nanowires Embedded with Self-assembled Quantum Dots
    (Wiley-VCH Verlag, 2008-03-25) C.-W. Hsu; A. Ganguly; C.-H. Liang; Y.-T. Hung; C.-T. Wu; G.-M. Hsu; Y.-F. Chen; Chia-Chun Chen; K.-H. Chen; L.-C. Chen
    We report the structure and emission properties of ternary (In,Ga)N nanowires (NWs) embedded with self-assembled quantum dots (SAQDs). InGaN NWs are fabricated by the reaction of In, Ga and NH3 via a vapor–liquid–solid (VLS) mechanism, using Au as the catalyst. By simply varying the growth temperature, In-rich or Ga-rich ternary NWs have been produced. X-ray diffraction, Raman studies and transmission electron microscopy reveal a phase-separated microstructure wherein the isovalent heteroatoms are self-aggregated, forming SAQDs embedded in NWs. The SAQDs are observed to dominate the emission behavior of both In-rich and Ga-rich NWs. Temperature-dependent photoluminescence (PL) measurements indicate relaxation of excited electrons from the matrix of the Ga-rich NWs to their embedded SAQDs. A multi-level band schema is proposed for the case of In-rich NWs, which showed an anomalous enhancement in the PL peak intensity with increasing temperature accompanies with red shift in its peak position.
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    Electronic Structures of Group-III-Nitride Nanorods Studied by X-ray Absorption, X-ray Emission, and Raman Spectroscopy
    (American Institute of Physics, 2006-05-29) C.-W. Pao; P.-D. Babu; H.-M. Tsai; J.-W. Chiou; S.-C. Ray; S.-C. Yang; F.-Z. Chien; W.-F. Pong; M.-H. Tsai; C.-W. Hsu; L.-C. Chen; Chia-Chun Chen; K.-H. Chen; H.-J. Lin; J.-F. Lee; J.-H. Guo
    Nitrogen (N) and metal (Al, Ga, and In) K-edge x-ray absorption near-edge structure (XANES), x-ray emission spectroscopy (XES), and Raman scattering measurements were performed to elucidate the electronic structures of group-III–nitride nanorods and thin films of AlN, GaN, and InN. XANES spectra show slight increase of the numbers of unoccupied N p states in GaN and AlN nanorods, which may be attributed to a slight increase of the degree of localization of conduction band states. The band gaps of AlN, GaN, and InN nanorods are determined by an overlay of XES and XANES spectra to be 6.2, 3.5, and 1.9 eV, respectively, which are close to those of AlN and GaN bulk/films and InN polycrystals.
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    Controlled Growth of Aluminium Nitride Nanorod Arrays via Chemical Vapour Deposition
    (IOP Publishing, 2006-06-14) J. Yang; T.-W. Liu; C.-W. Hsu; L.-C. Chen; K.-H. Chen; Chia-Chun Chen
    Large-area and high-density arrays of AlN nanorods were synthesized at low temperature via a template-free and catalyst-free chemical vapour deposition. The quasi-aligned AlN nanorods were identified to grow along the c-axis and preferentially orient with their growth direction perpendicular to the substrate. Further studies showed that the AlN nanorods were grown on a buffer layer formed at the beginning of the reaction. By changing the flow rate of the carrier gas at the beginning of the reaction, we successfully obtained nanorods with different orientations on the substrate. The Raman spectrum and cathodoluminescence spectrum of the AlN nanorods at room temperature reveal the existence of oxygen-related defects in the nanorods.