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The inverse-micellar preparation of Si nanoparticles (Nps) was improved by utilizing sodium naphthalide. The Si Nps were subsequently functionalized with 4-vinylbenzoic acid for their attachment onto TiO(2) films of dye-sensitized solar cells (DSSCs). The average diameter of the COOH-functionalized Si (Si-COOH) Nps was 4.6(±1.7) nm. Depth profiling by secondary-ion mass spectrometry revealed that the Si Nps were uniformly attached onto the TiO(2) films. The number of Ru(II) dye molecules adsorbed onto a TiO(2) film that was treated with the Si-COOH Nps was 42 % higher than that on the untreated TiO(2) film. As a result, DSSCs that incorporated the Si-COOH Nps exhibited higher short-circuit photocurrent density and an overall energy-conversion efficiency than the untreated DSSCs by 22 % and 27 %, respectively. This enhanced performance, mostly owing to the intramolecular charge-transfer to TiO(2) from the dye molecules that were anchored to the Si-COOH Nps, was confirmed by comparing the performance with two different Ru(II) -bipyridine dyes (N719 and N749).

Within the field of archeology, textile research is of growing interest because of its potential to provide relevant information regarding either the development or the technological advancement of ancient populations or the socio-economic and religious purposes of textile production. It is of paramount importance in cultural heritage research to use non-destructive techniques. Therefore, dye analyses were performed using two non-destructive methods: time-of-flight secondary ion mass spectrometry (TOF-SIMS) and Fourier transform infrared spectroscopy (FT-IR). In order to build a database, standard samples of dyed silk were prepared using several natural dye compounds; these samples were then analyzed with FT-IR and TOF-SIMS. Afterwards, spectroscopic analyses were carried out on five textile fragments coming from the 16th to the 18th century Korean tombs. FT-IR and TOF-SIMS spectra allowed the identification of fiber of the archeological textiles, making it possible to distinguish between the cotton and silk fibers. Furthermore, it was possible to identify indigo in three blue fabrics and to show its presence in a green textile. The results suggest that FT-IR and TOF-SIMS are two efficient and very helpful techniques for the characterization of excavated fabrics. Copyright © 2011 John Wiley & Sons, Ltd.

The morphology from symmetric diblock copolymers of poly(styrene-b-propylmethacrylate) (PS-PPrMA), where polystyrene (PS) block was perdeuterated near the copolymer/air and copolymer/substrate interfaces and in the bulk, was characterized by using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Elemental depth profiles measured in the negative ion mode by a Cs + primary ion beam demonstrate variations in hydrogen, deuterium, carbon, oxygen and hydrocarbons within the diblock copolymer according to the depth. The annealed deuterated poly(styrene-b-propy[methacrylate) (dPS-PPrMA) copolymer samples showed a decrease in the deuterated PS secondary ion peak intensity as compared to the as-cast samples. TOF-SIMS depth profiling was obtained for the lamellar morphology of dPS-PPrMA which is found to orient parallel to the surface of the substrate. This preferential orientation resulted in a periodic variation in the composition of each block that continued through the entire copolymer film with thickness of 700 and 2100A. Temperature-dependent annealing studies on dPS-PPrMA thin film on the silicon substrates were performed to investigate the lower critical ordering transition (LCOT) properties of diblock copolymers.

A surface-induced orientation of symmetric, deuterated polystyrene/poly(propyl methacrylate) diblock copolymers, dPS-PPrMA with different molecular weights (Mn = 135 000, 119 600, and 75 300) was investigated using time-of-flight secondary ion mass spectrometry (TOF-SIMS). Elemental depth profiles obtained in the negative ion mode by a Cs+ primary ion beam demonstrate variations in hydrogen, deuterium, carbon, oxygen, and hydrocarbons within the diblock copolymer according to the depth. Solution casting films of the copolymers with thicknesses of 700 and 2100 A exhibited no preferential orientation of the microdomain morphology with respect to the surface at room temperature. Annealing the copolymer films at 215 °C for 4 h produced a dramatic orientation of the microdomains parallel to the surface of the film. This preferential alignment provided regular oscillation in the composition of both blocks, which continued through the entire film. The periodicity as determined from a depth profile of TOF-SIMS showed good agreement with the results of small-angle X-ray scattering. Positive and negative ion molecular depth profiles by a C60+ cluster ion beam also provide information pertaining to the lower disorder–order transition (LDOT) behavior of the dPS-PPrMA copolymer. Depth profile results indicate a PPrMA layer preferentially located at the copolymer/silicon substrate interface. The microdomain separation processes of dPS-PPrMA were investigated as a function of the annealing temperature and time. Copyright © 2010 John Wiley & Sons, Ltd.

Five new monoacylglycerols (MAGs) were isolated from the marine sponge Stelletta sp. by reversed-phase high-performance liquid chromatography and analyzed by positive ion fast atom bombardment mass spectrometry (FAB-MS). FAB mass spectra of these compounds produced abundant sodium-adducted molecules [M+Na]+ from a mixture of 3-nitrobenzyl alcohol and sodium iodide. The structural elucidation of these sponge MAGs was carried out by FAB tandem mass spectrometry (MS/MS). To find diagnostic ions for the characterization of the MAGs, authentic MAGs were initially analyzed by collision-induced dissociation (CID) MS/MS. The CID MS/MS of [M+Na]+ precursor ions resulted in the formation of numerous characteristic product ions via a series of dissociative processes. The product ions formed by charge-remote fragmentation (CRF) provided important information for the characterization of acyl chains substituted at the glycerol backbone, and product ions at m/z 84, 97, 113 and 139 were diagnostic for the sodiated glycerol backbone. On the basis of these fragmentation patterns, the structures of five MAGs extracted from marine sponge were elucidated. In addition, high-resolution mass measurement was performed to obtain the elemental compositions of the MAGs. Copyright © 2007 John Wiley & Sons, Ltd.

Three cyclitol derivatives were isolated from the marine sponge Sarcotragus sp. by reversed-phase high-performance liquid chromatography and analyzed by fast-atom bombardment mass spectrometry (FAB-MS). Their structural elucidation was carried out with FAB tandem mass spectrometry (FAB-MS/MS). FAB-MS spectra produced a significant abundance of the sodium adducts [M+Na]+ and [M+2Na-H]+ from a mixture of m-NBA and NaI. In addition, trifluoroacetylation of the cyclitol derivatives was used for confirmation of the presence of the cyclitol ring. High abundance [M-5H+5CF3CO+Na]+ ions were observed in the FAB-MS spectra of the trifluoroacetyl-cyclitol derivatives. Collision-induced dissociation (CID) of the [M+Na]+ ions produced diverse product ions via a series of dissociative processes. Charge-remote fragmentation (CRF) patterns of [M+Na]+ ions were very useful for the identification of product ions which are characteristic for the cyclitol ring and long hydrocarbon chains substituted at the glycerol backbone. Moreover, the CID-MS/MS spectra of the [M+Na]+ ions yielded characteristic product ions at m/z 53, 83, 113, 155 and 171 for the cyclitol moiety, and at m/z 213, 229 and 245 for the glycerol backbone attached to the cyclitol ring.