Among items appearing in this issue are the following:

Two important events for the platinum industry are commemorated in the October 1999 issue of Platinum Metals Review. First, the discovery 75 years ago of the largest known source of platinum in the world, the Merensky Reef in South Africa, named after its discoverer, Hans Merensky. This is recounted by Professor R. Grant Cawthorn, the Platinum Industry’s Professor of Igneous Petrology at the University of the Witwatersrand in Johannesburg, South Africa. Second, Martyn Twigg, of the Johnson Matthey Catalytic Systems Division, recounts the background to the manufacture, 25 years ago, of the first autocatalysts for cleaning up automobile exhaust emissions. Autocatalysts have made a major contribution towards improving urban air quality, preventing the release of many millions of tons of pollutants into the atmosphere.

Most Heck reactions for the construction of carbon-carbon bonds are undertaken using homogeneous catalysts. David J. Ager, Scott A. Laneman, Amihai Eisenstadt and Valerie M. Wall from NSC Technologies in Illinois, U.S.A., discuss some of these reactions and look at other systems in which the Heck reaction has been used heterogeneously. In particular, they mention the use of a catalyst of palladium supported on carbon for the production of cinnamic acids, which are substrates for the synthesis of "unnatural" amino acids.

Fuel cells are increasingly being used around the world for mobile and stationary applications in both large and small devices. Many joint ventures have been formed to exploit the technology, and much research and development is being done both in universities and industry to bring fuel cells to market. Successful developments in this area, reported recently at the Sixth Grove Fuel Cell Symposium in London, are reviewed by Donald Cameron of the Interact Consultancy. Fuel cell technology for the production of clean energy is reported to be rapidly reaching commercialisation.

Thin high purity platinum films have been produced by scientists working at CNR Institutes in Padua and Rome, Italy, using metal organic chemical vapour deposition (MOCVD) with a new platinum precursor. A similar technique was successfully utilised by a group in New Mexico, U.S.A., to deposit thin conductive films of ruthenium dioxide.

The triannual conferences on the Chemistry of the Platinum Group Metals continue to present exciting work on developments across the wide spectrum of platinum group metals chemistry. Chris Barnard of the Johnson Matthey Technology Centre and Will Weston of Johnson Matthey’s Chemicals Development describe some of the work presented, including: (a) ring opening metathesis polymerisations, (b) separation of catalyst systems, (c) chelating ligands, (d) screening catalysts, (e) supramolecular structures, (f) developments in co-ordination chemistry, and (g) biomedical applications.

A highly selective sensor for liquid petroleum gas (LPG) is being developed by scientists at the University of L’Aquila, Italy and the Indian Institute of Chemical Technology, Hyderabad, India. The sensor uses palladium, aluminium silicate and tin oxide, and detects LPG in air, even in the presence of carbon monoxide and methane.

A method developed at the University of Cyprus for the optical detection of hydrogen utilising thin palladium films is described by Professor Constantinos Christofides, Kyriacos Kalli and Andreas Othonos. Using laser light they detected fractional changes in reflectivity corresponding to different concentrations of hydrogen in air.

A microelectrode for measuring the transmembrane potential of a biological cell has been developed by a group of scientists from EMPA, University of Zürich and ETH Zürich, Switzerland. The electrode is a sharp platinum/iridium needle, with a radius of curvature of 300 nm.

A method of attaching a platinum film to the polymer, poly(vinylidenefluoride), used for many electronic applications, has been developed by scientists from the Korea Institute of Science and Technology, Yonsei University and Chung Ju National University, Korea. By increasing the surface roughness of the polymer using argon ion irradiation, the platinum adhesion has been enhanced. Argon has also been utilised in sputtering by a group at the Oak Ridge National Laboratory in the U.S.A. to prepare porous platinum oxide films of large surface area. On reduction porous platinum was obtained which should find use as electrode material.

Sarah Elgafi of Johnson Matthey’s Chemicals Development reviews a special edition of the Journal of Molecular Catalysis A: Chemical which covers recent achievements in carbonylation reactions.

The October 1999 issue ends with a selection of abstracts of the most recently published literature and patents, and the annual Name and Subject Indexes.

Platinum Metals Review is available on the internet from the publications section of the Platinum Today site or from the host site www.ingentaselect.com.

Susan V. Ashton
Editor

Anyone with an active interest in the platinum group metals and their uses who does not have ready access to a copy of Platinum Metals Review and who may benefit from reading it, is invited to request a specimen copy from:

The Editor, Johnson Matthey PLC, Orchard Road, Royston, Hertfordshire SG8 5HE, United Kingdom; Fax +44 (0) 1763 256359; Email jmpmr@matthey.com