Prof. Michael L. Hitchman
Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK

In the mid-1970s I was working at the RCA Laboratories in Zurich and was developing my electrochemical interests. I moved on to a burgeoning field of commercial development with electrochemically based electrochromic displays. However, that came to an abrupt halt when I conclusively showed that the materials being used were thermodynamically unstable!

At that point I had talked myself out of a job and I needed quickly to find alternative research to occupy me. Fortunately, I became aware of work in an adjoining lab on CVD which I saw was a process with features very much akin to those found in electrochemistry; indeed, at that time CVD was often referred to as ‘gas plating’ by analogy with electroplating.

And that was when I first came across the name of Georg Wahl. He had started working at the central research laboratory of BBC (later ABB) in Heidelberg in 1969, and had rapidly established himself as a leading light in the area of CVD. The research in that area was vey much empirically based at that time, but as a result of his mathematical insights and analysis of heat and mass transfer processes related to reactor design he began to bring some scientific understanding to the complexities of CVD. He inspired me to start mathematically modelling CVD systems that were of
interest to my employers and, as result, my tenure with the company was no longer under threat!

I got to know Georg personally when we met at conferences, especially the EuroCVD conferences, and we were able to enjoy ‘talking CVD’ as well as discussing nontechnical matters. During those years he was the German representative on the EuroCVD Board and I became the British one, so together we participated with our European colleagues in maintaining and developing the extremely popular EuroCVD biennial meetings.

Our careers developed in parallel and I was so pleased when we were able to link up through his contribution of a chapter on protective coatings in the volume I edited with Klavs Jensen on CVD Principles and Applications (Academic Press, 1993). It was an even greater pleasure, indeed an honour, when he invited me ten years later to participate in the colloquium in Braunschweig to mark the occasion of his retirement.

Over the years that I knew him, it was always a delight to meet Georg, to share our CVD experiences and to get to know each other better. From those meetings I learnt of his eclectic and erudite interests, but I never had the extensive contact with him that the contributors to the following essays had. The six essays paint a marvellous picture of the really remarkable scientist that Georg was, and, at the same time, show that he was truly a renaissance man whose passion for his work and for life had such a powerful influence on the lives of others.

The essays presented here expand upon a selection published with an Editorial by Wiley-VCH in Advanced Materials Interfaces, Volume 6, Issue 24, December 20, 2019.
I am so glad that we can dedicate this web site with the full essays to the memory of Georg Wahl.

Professor Michael Hitchman
Emeritus Professor
Department of Pure and Applied Chemistry
University of Strathclyde
Glasgow, UK