02657nas a2200241 4500008004100000022001400041245005700055210005600112260009200168300001200260490000800272520186700280653000802147653002402155653002002179653003502199653001002234653000802244100002502252700002402277700002602301856008802327 2005 eng d a1042-015000aSurface disorder in c-Si induced by swift heavy ions0 aSurface disorder in cSi induced by swift heavy ions a4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLANDbTAYLOR & FRANCIS LTDcJUN a207-2180 v1603 a

The disorders induced in crystalline silicon (c-Si) through the process of electronic energy loss in the swift heavy ion irradiation were investigated. A number of silicon <100> samples were irradiated with 65 MeV oxygen ions at different fluences, 1x10(13) to 1.5x10(14) ions/cm(2), and characterized by the Raman spectroscopy, the optical reflectivity, the X-ray reflectivity, the atomic force microscopy (AFM) and the X-ray diffraction (XRD) techniques. The intensity, redshift, phonon coherence length and asymmetric broadening associated with the Raman peaks reveal that stressed and disordered lattice zones are produced in the surface region of the irradiated silicon. The average crystallite size, obtained by analyzing Raman spectrum with the phonon confinement model, was very large in the virgin silicon but decreased to <100 nm dimension in the ion irradiated silicon. The results of the X-ray reflectivity, AFM and optical reflectivity of 200-700 nm radiation indicate that the roughness of the silicon surface has enhanced substantially after ion irradiation. The diffusion of oxygen in silicon surface during ion irradiation is evident from the oscillation in the X-ray reflectivity spectrum and the sharp decrease in the reflectivity of 200-400 nm radiation. The rise in temperature, estimated from the heat spike model, was high enough to melt the local silicon surface. The results of XRD indicate that lattice defects have been induced and a new plane <211> has been formed in the silicon <100> after ion irradiation. The results of the present study show that the energy deposited in crystalline silicon through the process of electronic energy loss similar to 0.944 keV/nm per ion is sufficient to induce disorders of appreciable magnitude in the silicon surface even at a fluence of similar to 10(13) ions/cm(2).

10aAFM10acrystalline silicon10aion irradiation10aoptical and X-ray reflectivity10aRaman10aXRD1 aBogle, Kashinath, A.1 aGokhale, Suresh, P.1 aBhoraskar, Vasant, N. uhttps://library.ncl.res.in/content/surface-disorder-c-si-induced-swift-heavy-ions-001771nas a2200253 4500008004100000022001400041245009900055210006900154260007300223300001400296490000700310520087300317653003001190653000901220653001301229653002501242653000801267100002201275700002501297700002001322700001901342700002601361856013001387 2006 eng d a0167-577X00aElectron beam induced surface cross-linking of functional monomers coated on silicon substrate0 aElectron beam induced surface crosslinking of functional monomer aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAY a1360-13650 v603 a

A 3: 1 composition of functional monomer: multifunctional acrylate was spin coated and later cross-linked under the influence of keV electron irradiation on the surface of silicon to generate a surface-anchored cross-linked network bearing functional moieties. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) as well as wetting angle measurements were used for the analysis of functional monomer cross-linked surfaces. Results of the surface reconstruction of surfaces and electron irradiated on coated silicon wafers reveal that long-term hydrophilic surfaces can be achieved. Thus, the surface architecture can be favorably manipulated by using this remarkable technique with a Suitable combination of functional monomers and cross-linkers. (c) 2005 Elsevier B.V. All rights reserved.

10aelectron beam irradiation10aFTIR10aPolymers10asurface modification10aXPS1 aMahapatra, S., K.1 aBodas, Dhananjay, S.1 aMandale, A., B.1 aGangal, S., A.1 aBhoraskar, Vasant, N. uhttps://library.ncl.res.in/content/electron-beam-induced-surface-cross-linking-functional-monomers-coated-silicon-substrate-002409nas a2200289 4500008004100000022001400041245009300055210006900148260009200217300001200309490000800321520145200329653001801781653001501799653000801814653000901822653001401831653000801845653001601853653000801869100003001877700002001907700002201927700002001949700002601969856012401995 2006 eng d a1042-015000aIrradiation effects of 12 eV oxygen ions on polyimide and fluorinated ethylene propylene0 aIrradiation effects of 12 eV oxygen ions on polyimide and fluori a4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLANDbTAYLOR & FRANCIS LTDcAUG a495-5040 v1613 a

Polyimide (PI) and Fluorinated Ethylene Propylene (FEP) samples (15mm x 15mm x 50 mu m ) were exposed to atomic oxygen ions of average energy similar to 12 eV and flux similar to 5x10(13) ions cm(-2) s(-1) , produced in the Electron Cyclotron Resonance (ECR) plasma. The energy and the flux of the oxygen ions at different positions in the plasma were measured by a retarding field analyzer. The fluence of the oxygen ions was varied from sample to sample in the range of similar to 5x10(16) to 2x10(17) ions cm(-2) by changing the irradiation period. The pre- and the post-irradiated samples were characterized by the weight loss, Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), and Fourier Transform Infrared (FTIR) techniques. The weight of the PI and FEP samples decreased with increasing the ion fluence. However, the erosion yield for the PI is found to be higher, by almost a factor five, when compared with that of FEP. On the surface region of irradiated samples, the concentrations of the carbon, fluorine, and oxygen and their corresponding chemical bonds have changed appreciably. Moreover, blisters and nanoglobules were also observed even at a fluence of similar to 10(17) ions cm(-2) . This oxygen ion fluence is almost two orders of magnitude lower than that of the 5 eV atomic oxygen, which a satellite encounters in the space, at the low Earth orbit, during its mission period of about 7 years.

10aatomic oxygen10aECR plasma10aFEP10aFTIR10aPolyimide10aSEM10aweight loss10aXPS1 aMajeed, Riyadh, M A Abdul1 aPurohit, V., S.1 aBhoraskar, S., V.1 aMandale, A., B.1 aBhoraskar, Vasant, N. uhttps://library.ncl.res.in/content/irradiation-effects-12-ev-oxygen-ions-polyimide-and-fluorinated-ethylene-propylene-001826nas a2200205 4500008004100000022001400041245007500055210006900130260008000199300001400279490000700293520107700300100003001377700002101407700001801428700002001446700002201466700002601488856010601514 2006 eng d a0022-372700aNitridation of high speed steel by electron cyclotron resonance plasma0 aNitridation of high speed steel by electron cyclotron resonance  aDIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcMAY a2109-21130 v393 a

Plasma nitridation of high speed M2 steel is studied using a microwave assisted electron cyclotron resonance plasma source. A mixture of hydrogen and nitrogen with a proportion of 7 : 3 was used as the nitriding gas. The density of plasma for this forming gas was measured to be similar to 10(18) m(-3) as estimated by a double probe method. The M2 steel was nitrided at various temperatures of 400, 450, 500 and 550 degrees C under similar reactor conditions. The nitrided layer was characterized by using various analytical techniques which included structural, morphological, chemical and microhardness measurement. The maximum thickness of the nitrided layer was found to be 48 mu m for samples nitrided at 550 degrees C. No layer corresponding to white/compound layer is seen in our analysis. The hardness is seen to increase from similar to 580HV to similar to 1190HV for samples nitrided at 550 degrees C. Electron cyclotron resonance plasma nitridation is observed to be much faster and a cleaner process as compared with the conventional nitriding process.

1 aMajeed, Riyadh, M A Abdul1 aPurohit, Vishwas1 aBhide, Rajesh1 aMandale, A., B.1 aBhoraskar, S., V.1 aBhoraskar, Vasant, N. uhttps://library.ncl.res.in/content/nitridation-high-speed-steel-electron-cyclotron-resonance-plasma-002727nas a2200253 4500008004100000022001400041245013800055210006900193260007100262300001200333490000700345520177100352100002502123700001902148700002202167700002602189700001802215700001902233700002402252700002302276700001802299700002902317856012702346 2008 eng d a0897-475600aCo : CdS diluted magnetic semiconductor nanoparticles: radiation synthesis, dopant-defect complex formation, and unexpected magnetism0 aCo CdS diluted magnetic semiconductor nanoparticles radiation sy a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJAN a440-4460 v203 a

Incorporating a dopant into a nanoparticle is a nontrivial proposition in view of the size dependent surface versus bulk energy considerations and the intrinsic proximity of the surface to the interior, which facilitates migration to the surface. If realized and controlled, however, it can open up new avenues to novel nanomaterials. Some previous studies have shown the dopability of nanosystems but only with specific surface functionalization. Here, we demonstrate the successful dopant incorporation via a new route of pulsed high energy electron induced synthesis. We choose a system Co:CdS (dilutely cobalt doped cadmium sulfide) in view of the well-known application-worthy properties of CdS and the potential possibility of its conversion to a diluted magnetic semiconductor of interest to spintronics. By using various techniques, we show that matrix incorporation and uniform distribution of cobalt are realized in US nanocrystals without the need for additional chemical or physical manipulation. Optical and photoluminescence properties also support dopant incorporation. Interestingly, although magnetism is realized, it is weak, and it decreases at higher cobalt concentration. First principle density functional calculations are performed to understand this counterintuitive behavior. These calculations suggest that the introduction of parent cation or anion vacancies lead to magnetic moment reduction, albeit marginally. However, with some Co impurity fraction in the octahedral interstitial site inside the wurtzite cage, the magnetic moment drops down drastically. This study reveals that defect states may have an interesting role in dopant stabilization in nanosystems, with interesting system dependent consequences for the properties.

1 aBogle, Kashinath, A.1 aGhosh, Saurabh1 aDhole, Sanjay, D.1 aBhoraskar, Vasant, N.1 aFu, Lian-feng1 aChi, Miao-Fang1 aBrowning, Nigel, D.1 aKundaliya, Darshan1 aDas, Gour, P.1 aOgale, Satishchandra, B. uhttps://library.ncl.res.in/content/co-cds-diluted-magnetic-semiconductor-nanoparticles-radiation-synthesis-dopant-defect-002050nas a2200277 4500008004100000022001400041245007300055210006900128260007300197300001400270490000700284520108200291653002401373653003701397653002901434653002101463653001301484653003101497100002501528700002401553700002101577700002601598700002201624700002201646856010401668 2011 eng d a0167-577X00aSynthesis of cube-shaped gold nanostructures by electron irradiation0 aSynthesis of cubeshaped gold nanostructures by electron irradiat aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUN a1605-16070 v653 a

The needle-like gold nanostructures were synthesized by using chloroauric acid (HAuCl(4)) as a metal precursor and sodium borohydride (NaBH(4)) as the reducing agent. These needle-like nanostructures of gold were irradiated with high energy electrons (E-6 MeV, phi similar to 10(12) e cm(-2) s(-1)). The pre- and post-irradiated gold nanostructures were characterized by Scanning Electron Microscopy (SEM), UV-vis spectroscopy, X-ray Diffraction (XRD) and contact angle measurement (GBX-Model Digidrop) techniques. The results of the SEM revealed that after electron irradiation, the needle-like gold structures got fragmented into identical cube-shaped gold nanostructures, though of different sizes. The XRD analysis indicated that the average crystallite size of the gold nanostructures remained unchanged even after irradiation with high energy electrons. A glass surface showed hydrophilic behavior when coated with needle-like nanostructures and became ultra hydrophilic when coated with cube-shaped gold nanostructures. (C) 2011 Elsevier B.V. All rights reserved.

10aGold nanostructures10aHigh energy electron irradiation10aNanostructured materials10aRadiation damage10aSurfaces10aUltra hydrophilic surfaces1 aDhumale, Vinayak, A.1 aGangwar, Rajesh, K.1 aShah, Preeti, V.1 aBhoraskar, Vasant, N.1 aMulla, Imtiaz, S.1 aSharma, Rishi, B. uhttps://library.ncl.res.in/content/synthesis-cube-shaped-gold-nanostructures-electron-irradiation-001944nas a2200301 4500008004100000022001400041245009700055210006900152260008100221300001100302490000700313520092500320653002701245653000701272653002501279653001401304100001601318700001801334700001701352700001501369700001701384700002401401700002101425700002601446700002301472700002201495856012501517 2015 eng d a0022-372700aReduction of graphene oxide by 100 MeV Au ion irradiation and its application as H2O2 sensor0 aReduction of graphene oxide by 100 MeV Au ion irradiation and it aTEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcSEP a3651050 v483 a

Graphene oxide (GO) synthesized from a modified Hummer's method was reduced (referred, rGO) by using 100 MeV Au ion species and its response to the sense H2O2 was investigated. The changes in the atomic composition and structural properties of rGO after irradiation were studied using x-ray diffraction, Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy. These results suggested that the removal of the oxygen-containing functional groups and the improvement of the electrochemical performance of reduced graphene oxide (rGO) after ion irradiation. Raman spectroscopic results revealed the increase in the disorder parameter (I-D/I-G) after Au ion irradiation and also the formation of a large number of small sp(2) domains due to the electronic energy loss of ion beam. The resultant rGO was investigated for H2O2 sensing using electrochemical techniques and it showed a good response.

10aelectronic energy loss10aGO10aion beam irradiation10areduction1 aHareesh, K.1 aJoshi, R., P.1 aShateesh, B.1 aAsokan, K.1 aKanjilal, D.1 aLate, Dattatray, J.1 aDahiwale, S., S.1 aBhoraskar, Vasant, N.1 aHaram, Santosh, K.1 aDhole, Sanjay, D. uhttps://library.ncl.res.in/content/reduction-graphene-oxide-100-mev-au-ion-irradiation-and-its-application-h2o2-sensor-1