Ammonia borane (AB) was loaded onto a range of mesoporous materials (MCM-41, SBA-15 and MCF) by wet impregnation from THF solutions and its thermal dehydrogenation studied using TGA/MS. The interactions between the AB and the surfaces were characterised using difference FTIR spectroscopy. The presence of mesoporous materials promotes lower temperature H 2 release, and greater selectivity towards the formation of H 2 , i.e. decreased formation of gaseous boroncontaining side products. D-FTIR results confirm interactions between isolated silanol groups or surface Si-O-Si species and AB and this supports the proposal that a H-bonding interaction between the surface and deposited AB is important in promoting decomposition at lower temperature. AB interacting with silanol groups decomposes more readily than that coordinated to Si-O-Si. The effect on the temperature of H 2 release is greater for materials of larger pore size (rather than materials of larger surface area), i.e. MCF>SBA-15>MCM-41. This suggests that access to the internal surface of the mesoporous material (where the majority of surface silanols are located) is important, and this in turn suggests that polymeric species, which may have restricted access to the internal surface of the different materials, form when AB is dissolved in THF. Decomposition of B-N-containing gaseous materials (to AB(g)) following their formation, on the silanol groups of the SiO 2 , is suggested as the reason for the increased selectivity of the reaction to H 2 (and decreased release of unwanted side products) in the presence of mesoporous material.

Publication information Journal of Photochemistry and Photobiology A-Chemistry, 289 :Publisher Elsevier Item record/more information http://hdl.handle.net/10197/5640 Publisher's statementThis is the author's version of a work that was accepted for publication in Journal of Photochemistry and Photobiology A: Chemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Photochemistry and Photobilogy (VOL 289, ISSUE 2014, (2014 AbstractIn this work, different thermal treatments of titanium isopropoxide-derived photo-catalyst precursors, designed with the purpose of generating C-doped TiO 2 photo-catalysts using carbon atoms present in the TiOx gel precursors as dopants, are presented. Specifically, these look at varying the standard calcination techniques using heat treatments in He (rather than calcination in air) and lower temperature calcinations (200 °C rather than 500 °C). The formed materials are characterised using N 2 physisorption, XRD, UV Visible spectroscopy and XPS and their activities in promoting the oxidation of 4-chlorophenol under visible-light-only conditions were analysed. The nature of carbon remaining on the (or in the) material is discussed found to be both surface graphitic carbon and carbon present in anionic dopant positions. The different contributions of each type of carbon to the catalytic photo-activity under visible light are discussed.

The paramagnetic susceptibilities of khe anhydrous stearates and laurates of nickel, cobalt, and iron and of copper stearate are reported. Results are included for the hydrated forms of cobalt and nickel laurates. Measurements a t five different temperatures in the range 105-333" K show that only the copper carboxylates fail to obey a Curie-Weiss law. The magnetic moments of the ferric compounds, however, are anomalously low, and the Weiss constant 8 is very large.

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