Perhaps even more important, opportunities for unexpected discoveries are being lost.

The committee believes that there is no lack of good ideas to be explored. For example, laser-assisted chemical processing is a new approach for synthesis of metals as films or deposited wires. It has recently been demonstrated that metals such as copper, gold, chromium, and cadmium can be thermally deposited with laser assist onto surfaces by using the appropriate organometallic precursor. Similarly, relatively cool plasmas are being used to pyrolyze hydrocarbons into carbon radicals that deposit as diamond films. The engineering of industrial-scale plasma processes presents major challenges. With hot plasmas, it may be necessary to cool the gases at rates of millions of degrees per second in order to trap the thermodynamically unstable species that are necessary for synthesis.

There is also an opportunity for stronger efforts aimed at improving catalytic processes. Major progress is being made these days in understanding the structures of surfaces and how they function as catalysts. The ability to modify such surfaces chemically at the angstrom level—for example, via molecular beam epitaxy or atomic layer epitaxy—offers opportunities for the design of completely new types of catalytic systems.

A final example of novel synthesis concerns solid-state preparation techniques. The most commonly used methods involve reacting mixtures of powdered substances at high temperatures. Low-temperature methods, such as the increasingly popular sol-gel techniques, not only are more efficient but also allow the preparation of many new phases that are unstable at high temperatures. Again, there is no lack of opportunities for innovation. But innovation cannot occur unless there is financial support and institutional encouragement for research in synthesis.



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