2022 Kavli Prize For Nanoscience Awarded To Scientists For Self-Assembled Monolayers

The 2022 Kavli Prize in Nanoscience has been awarded to Professor David Allara of Pennsylvania State University, Professor Ralph Nuzzo of the University of Illinois at Urbana-Champaign, Professor Jacob Sagiv of the Weizmann Institute of Science and Professor George Whitesides of Harvard University for their contributions to and development of the field of self-assembled monolayers on solid substrates. The four winners will share the $1 million USD prize. The Kavli Prize is awarded every two years in three categories that celebrate the research successes of the big (astrophysics), the small (nanoscience), and the complex (neuroscience).

This year’s winners truly represent the iceberg atop which modern scientific developments are perched. When materials interact, they do so through their surface chemistry – chemical composition, molecular arrangement, texture and robustness of a material’s surface layer all play a part in its functionality and reactivity. Materials science and engineering has long focused on refining materials to maximize their application and efficiency however, it was the dawn of nanoscience that really captured surface scientists’ imaginations. If we can engineer surfaces for specific applications and incorporate some of the properties of nanomaterials in the process, we can not only design but also fine-tune the way that materials interact with each other and their environment.

This field of research sits on centuries of scientific observation, with anecdotes dating back to Benjamin Franklin in 1773. Inspired by the fishing communities of Portugal and Bermuda who he had seen using oil on water to help them observe the fish in choppy waters, he poured a teaspoon of oil onto the pond in Clapham Common, London, and noticed a change in the waves on the surface, and the transformation of the pond’s surface into that of a smooth mirror. The oil had dispersed across the surface of the pond, creating a thin film that impacted the way that the surfaces interacted with light. This rapid dispersion of the oil further inspired Lord Rayleigh who, with the help of German chemist Agnes Pockels, published a paper confirming that molecules within these thin films arranged themselves uniformly across a liquid surface.

Two early pioneers of thin film synthesis built on this foundational research; Katherine Blodgett, the first woman to be awarded a PhD in physics from the University of Cambridge, and Irvine Langmuir, the Nobel Prize winning chemist and physicist who initially developed a method of creating single-molecule thin films on the surface of water. Blodgett and Langmuir worked together to develop, among other things, the first “invisible” glass by depositing a non-reflective thin film coating on glass. They developed a method by which they could deposit a monomolecular film onto glass. Through subsequent applications, they could further apply a specific number of monolayers, thus controlling the thickness of the coating. As these thin films were within the nanometre range, their nanostructures could be tailored to interact with visible light, with wavelengths also in the nanometre range, in bespoke ways. The team deposited 44 layers onto a piece of glass, which resulted in a reduction of reflectivity in the glass, and 99% transmission, vastly reducing reflective glare. This had a range of applications, notably including in cinematography.

The winners of the 2022 Kavli Prize in Nanoscience have continued to build on Langmuir and Blodgett’s work. Professor Sagiv first demonstrated the adsorption of different thin films onto a wider range of materials such as metal and glass. Professor Nuzzo and Professor Allara further developed this technique, with breakthroughs in stronger adsorption onto bare metal surfaces, and in the development of spectroscopic characterisation techniques to determine the properties of self-assembled monolayers. This has led to the design of monolayers with specific functionalities for a range of applications. Professor Whitesides’ work on patterned materials made from self-assembled monolayers has seen commercial success in everything from pharmacology to chemical sensors, and from electronics to medical diagnostics.

Self-assembled monolayers play a huge part in helping to solve our biggest global challenges, such as climate change. One way we can manage climate change is by using cleaner energy. This energy needs to be renewable or sustainable, and also cheap enough to be widely adopted. By indexing scientific publications on self-assembled monolayers from the last decade against the UN’s Sustainable Development Goals, we can see the impact that this technology is having on SDG 7, Affordable and Clean Energy, in particular, thanks in part to their application in battery technology, energy-harvesting thin film solar cells, and semiconductor devices.

Cutting edge science always sits on a broad base of foundational research, and the Kavli Foundation certainly recognises that. By celebrating such impactful contributions to science, the hope is that others will continue to build on the work of the latest winners of the Kavli Prize, and more novel applications will be developed to continue to help humanity overcome big challenges with small science.