Surface ruthenated hydrocarbon sensor: statistical optimisation of sensitivity

A surface functionalised gas sensing material capable of better sensitivity and selectivity is developed by grafting Ru-O linkages on the surface of t in oxide. A statistical technique is employed using a 2(7-3) fractional fac torial design to optimise the sensitivity of the ruthenated tin oxide towar ds hydrocarbons. A systematic evaluation of the mean effects of such a 2(7- 3) (i.e., 16) experiments indicates the usefulness of this powerful tool in optimising the sensitivity. Various results of characterisation techniques such as SEM, XPS and EDAX illustrate the reasons for optimum sensitivity i n terms of the amount and distribution of Ru species on the surface. A comp arison of the results obtained using such a 2(7-3) algorithm against the re sults of conventional experiments emphasises the importance of the interact ion of various experimental parameters during the sensor fabrication. (C) 2 000 Elsevier Science S.A. All rights reserved.