Surface Plasmon—Assisted Excitation of Atomic Visible Light Spectral Lines in the Impact of Highly Charged Ions 126Xeq＋ on Solid Surfaces

We measured the visible light spectral lines of sputtering atoms from solid surfaces orAl, Ti, Ni, Ta and Au which are impacted by 150 keV 126Xeq+ (6 ≤q ≤ 30). It is found that intensities of the light spectral lines are greatly and suddenly enhanced when the charge state of the ion is raised up to a critical value. If assuming that potential energy released from the incident ion due to capturing one electron is enough to excite a surface plasmon, we can estimate the critical charge states and obtain the results very well consistent with the measurements for the above-mentioned target materials. This means that a surface plasmon induced by one electron capture can enhance the excitation of atomic visible light spectral lines in the impact of a highly charged ion on a solid surface.

Preparation of Organic Semiconductor PTCDA and Studies on Its Crystal Structure and the Absorption Spectrum

Organic semiconductoe 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) has been synthetized with 1,8-naphthalic anhydride using chemical method.X-ray diffraction spectrum shows that it is monoclinic.Visible absorption spectrum shows that its gap band is 2.2 eV with singlet exciton bandwidth of 0.9 eV.

A comprehensive analysis of various structural parameters of Indian coals with the aid of advanced analytical tools

An exhaustive structural analysis was carried out on three Indian coals （ranging from sub-bituminous to high volatile bituminous coal） using a range of advanced characterization tools. Detailed investigations were carded out using UV-Visible spectroscopy, X-ray diffraction, scanning electron microscopy coupled energy dispersive spectroscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. The X-ray and Raman peaks were deconvoluted and analyzed in details. Coal crystallites possess turbostratic structure, whose crystallite diameter and height increase with rank. The tJdC ratio plotted against aromaticity exhibited a decreasing trend, confirming the graphitization of coal upon leaching. It is also found that, with the increase of coal rank, the dependency of I20/I26 on La is saturated, due to the increase in average size of sp2 nanoclusters. In Raman spectra, the observed G peak （1585 cm^-1） and the D2 band arises from graphitic lattices. In IR spectrum, two distinct peaks at 2850 and 2920 cm i are attributed to the symmetric and asymmetric -CH2 stretching vibrations. The intense peak at - 1620 cm^-1, is either attributed to the aromatic ring stretching of C=C nucleus.

测量托卡马克可见光谱辐射的低噪声、高响应光敏二极管探测器

研制了一种用于托卡马克等离子体可见光谱线测量的半导体光敏二极管探测器。这种探测器具有体积小、造价低、使用方便等优点，它具有很高的量子效率、理想的线性区、宽的频率范围和低的噪声，完全能够满足托卡马克诊断中对等离子体可见光微弱谱线的测量。

Size-controlled chalcopyrite CuInS_2 nanocrystals:One-pot synthesis and optical characterization

Chalcopyrite ternary CulnS2 semiconductor nanocry stals have been synthesized via a facile one-pot chemical approach by using oleylamine and oleic acid as solvents. The as-prepared CuInS2 nanocrystals have been characterized by instrumental analyses such as X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscopy （TEM）/high-resolution TEM （HRTEM）, energy-dispersive X-ray spectroscopy （EDS）, UV-vis absorption spectroscopy （UV-vis） and photoluminescence （PL） spectroscopy. The particle sizes of the CuInS2 nanocrystals could be tuned from 2 to 10 nm by simply varying reaction conditions. Oleylamine, which acted as both a reductant and an effective capping agent, plays an important role in the size-controlled synthesis of CulnS2 nanocrystals. Based on a series of comparative experiments under different reaction conditions, the probable formation mechanism of CulnS2 nanocrystals has been proposed. Furthermore, the UV-vis absorption and PL emission spectra of the chalcopyrite CulnS2 nanocrystals have been found to be adjustable in the range of 527-815 nm and 625-800 rim, respectively, indicating their potential application in photovoltaic devices.

Activating ZnO nanorod photoanodes in visible light by Cu ion implantation

Utilization of visible light is of crucial importance for exploiting efficient semiconductor catalysts for solar water splitting. In this study, an advanced ion implantation method was utilized to dope Cu ions into ZnO nanorod arrays for photoelectrochemical water splitting in visible light. X-ray diffraction （XRD） and X-ray photo-electron spectroscopy （XPS） results revealed that Cu^＋ together with a small amount of Cu^2＋ were highly dispersed within the ZnO nanorod arrays. The Cu ion doped ZnO nanorod arrays displayed extended optical absorption and enhanced photoelectrochemical performance under visible light illumination （A 〉 420 nm）. A considerable photocurrent density of 18 μA/cm^2 at 0.8 V （vs. a saturated calomel electrode） was achieved, which was about 11 times higher than that of undoped ZnO nanorod arrays. This study proposes that ion implantation could be an effective approach for developing novel visible-light-driven photocatalytic materials for water splitting.

Fabrication and characterization of amorphous ITO/p-Si heterojunction solar cell

Amorphous indium-tin-oxide(a-ITO) film was deposited by radio-frequency(RF) magnetron sputtering at 180°C substrate temperature on the texturized p-Si wafer to fabricate a-ITO/p-Si heterojunction solar cell.The microstructural,optical and electrical properties of the a-ITO film were characterized by XRD,SEM,XPS,UV-VIS spectrophotometer,four-point probe and Hall effect measurement,respectively.The electrical properties of heterojunction were investigated by I-V measurement,which reveals that the heterojunction shows strong rectifying behavior under a dark condition.The ideality factor and the saturation current density of this diode are 2.26 and 1.58×10-4 A cm-2,respectively.And the value of IF/IR(IF and IR stand for forward and reverse currents,respectively) at 1 V is found to be as high as 21.5.For the a-ITO/p-Si heterojunction solar cell,the a-ITO thin film acts not only as an emitter layer,but also as an anti-reflected coating film.The conversion efficiency of the fabricated a-ITO/p-Si heterojunction cell is approximately 1.1%,under 100 mW cm-2 illumination(AM1.5 condition).And the open-circuit voltage(Voc),short-circuit current density(J SC),filll factor(FF) are 280 mV,9.83 mA cm 2 and 39.9%,respectively.Because the ITO film deposited at low temperature is amorphous,it can effectively reduce the interface states between ITO and p-Si.The barrier height and internal electric field,which is near the surface of p-Si,can effectively be enhanced.Thus we can see the great photovoltaic effect.

An inverted triplesalen ligand by a convergent synthesis and its influence on trinuclear Fe_3~Ⅲ complexes

The inverted triplesalen ligand H6feldMe has been synthesized from 2,4,6-triformyl-phloroglucinol and a ketimine salen half-unit in a convergent synthesis. NMR, IR, and UV-vis spectroscopy reveal that this ligand is not in the O-protonated tau- tomer but in the N-protonated tautomer with substantial heteroradialene contribution. This ligand and the conventional triple- salen ligand H6talent-au2 have been used to synthesize the trinuclear Fem complexes [（feldMe）（FeCl）3] and [（talent-Bu2）（FeC1）3], respectively. The molecular structures of these complexes were obtained by single-crystal X-ray diffraction. Two trinuclear Fem complexes of [（feldMe）（FeCl）3] dimerize via two Fe-phenolate bonds, whereas due to steric hindrance no dimerization is observed for [（talent-Bu2）（FeC1）3]. The structural data also reveal some heteroradialene contribution in the trinuclear complexes. Whereas UV-vis and MOlSbauer spectroscopy are not suitable to distinguish between the two complexes, FT-IR spectra show characteristic features due to the different substitution patterns of the conventional and the inverted triplesalen ligands. Another handle is provided by electrochemistry. Whereas both complexes exhibit an irreversible oxidation wave （0.94 V vs. Fc＋/Fc for [（feldMe）（FeC1）3] and 0.84 V vs. Fc~/Fc for [（talent-Bu2）（FeC1）3]）, which is assigned to the oxidation of the central backbone, higher potential oxidations are reversible for [（talent-Bu2）（FeC1）3]） but irreversible for [（feldMe）（FeC1）3]. This is attributed to the reversible oxidation of the terminal phenolates in the di-tert-butyl substituted [（talentBu2）（FeCl）3] in contrast to the mono-methyl-substituted phenolates in [（feld^ae）（FeC1）3]. The magnetic properties of [（talen^-Bu2）（FeC1）3] reveal a very small ferromagnetic coupling with significant zero-field splitting of the Feul S = 5/2 ions. In contrast, the dimerization of two trinu- clear complexes in [（feldMe）（FeCl）3] results in antiferromagnetic interactions between the two phenolate-bridged FeIII ions, which mask the intra-trinuclear interactions transmitted by the central phloroglucinol backbone.

Thermostable Nitrogen-Doped HTiNbO5 Nanosheets with a High Visible-Light Photocatalytic Activity

Nitrogen-doped HTiNbO5 nanosheets have been successfully synthesized by first exfoliating layered HTiNbO5 in tetrabutylammonium hydroxide （TBAOH） to obtain HTiNbO5 nanosheets and then heating the nanosheets with urea. The resulting samples were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, energy-dispersive X-ray （EDX）, X-ray photoelectron spectroscopy （XPS）, UV-vis spectroscopy and N2 adsorption-desorption measurements. It was found that N-doping resulted in a much higher thermostability of the layered structure, intrinsic bandgap narrowing and a visible light response. The doped nitrogen atoms were mainly located in the interstitial sites of TiNbOs- lamellae and chemically bound to hydrogen ions. Compared with N-doped HTiNbOs, N-doped HTiNbO5 nanosheets had a much larger specific surface area and richer mesoporosity due to fee rather loose and irregular arrangement of fitanoniobate nanosheets. Both N-doped layered HTiNbOs and HTiNbO5 nanosheets showed a very high visible-light photocatalytic activity for the degradation of rhodamine B （RhB） aqueous solution. Moreover, due to the considerably larger surface area, richer mesoporosity and stronger acidity, N-doped HTiNbO5 nanosheets had an even higher activity than N-doped HTiNbOs, although the latter had a stronger absorption in the visible region. The dye molecules were mainly degraded to aliphatic organic compounds and partially mineralized to CO2 and/or CO, rather than being simply decolorized. The effect of photosensitization was insignificant and RhB was degraded mainly via the typical photocatalytic reaction routes. Two different reaction routes for the photodegradation of RhB under visible light irradiation over N-doped HTiNbO5 nanosheets have been proposed. The present method can be extended to a large number of layered metal oxides that have the characteristics of intercalation and exfoliation, thus providing new opportunities for the fabrication of highly effective and potentially practical visible-light photocatalysts.

Putting aniline radical cations in a bottle

Salts containing aniline radical cations have been isolated and characterized by electron paramagnetic resonance(EPR)spectroscopy, UV-Vis absorption spectroscopy and single crystal X-ray diffraction. The EPR spectra and theoretical calculations indicate the unpaired electron is delocalized on phenyl rings and nitrogen atoms. Both radical cations feature a quinoidal geometry with a partially double C–N bond, but are distinct in that the C–N bond is coplanar to the phenyl plane in one cation while deviates from the plane in the other due to steric crowding. The work provides the first unequivocal examples of stable aniline radical cations.