Nanoarchitectures Based on Layered Titanosilicates Supported on

Dec 27, 2012 - Because of the basic character of the synthesis media, silica from the ... of the titanosilicate nanosheets as a house-of-cards radiall...
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Article pubs.acs.org/Langmuir

Nanoarchitectures Based on Layered Titanosilicates Supported on Glass Fibers: Application to Hydrogen Storage Javier Pérez-Carvajal,† Pilar Aranda,† Angel Berenguer-Murcia,‡ Diego Cazorla-Amorós,‡ Joaquıń Coronas,§ and Eduardo Ruiz-Hitzky*,† †

Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco 28049, Madrid, Spain Departamento de Química Inorgánica e Instituto Universitario de Materiales, Universidad de Alicante, Apartado 99, E-03080 Alicante, Spain § Chemical & Environmental Engineering Department & Nanoscience Institute of Aragon (INA), Universidad de Zaragoza, 50018 Zaragoza, Spain ‡

S Supporting Information *

ABSTRACT: This work reports on the synthesis of nanosheets of layered titanosilicate JDF-L1 supported on commercial E-type glass fibers with the aim of developing novel nanoarchitectures useful as robust and easy to handle hydrogen adsorbents. The preparation of those materials is carried out by hydrothermal reaction from the corresponding gel precursor in the presence of the glass support. Because of the basic character of the synthesis media, silica from the silicatebased glass fibers can be involved in the reaction, cementing its associated titanosilicate and giving rise to strong linkages on the support with the result of very stable heterostructures. The nanoarchitectures built up by this approach promote the growth and disposition of the titanosilicate nanosheets as a house-of-cards radially distributed around the fiber axis. Such an open arrangement represents suitable geometry for potential uses in adsorption and catalytic applications where the active surface has to be available. The content of the titanosilicate crystalline phase in the system represents about 12 wt %, and this percentage of the adsorbent fraction can achieve, at 298 K and 20 MPa, 0.14 wt % hydrogen adsorption with respect to the total mass of the system. Following postsynthesis treatments, small amounts of Pd (5000

JDF-L1 3.9 (4.0)

a

JDF-L1@GF

Pd-JDF-L1@GF

33

32

Theoretical value calculated from the titanosilicate formula.

Pd-JDF-L1@GF sample are modified after Pd doping probably because of the alteration of the titanosilicates by the acidic media that provokes the Na+ exchange by H+ species.14 The presence of Pd nanoparticles cannot be distinguished in the X-ray diffractograms because they are present in a very low proportion in the nanoarchitecture (