Viewpoint pubs.acs.org/JPCL
The International Year of Light and the Chemistry Classroom
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crucial role in the behavior of Earth’s atmosphere. Photochemical events were almost certainly involved in the initial stages of the development of life on Earth, and life as we know it would not be possible without the process of photosynthesis. Human vision is reliant upon photochemistry that occurs in the retina, and light plays a crucial role in human health through the photochemistry of vitamin D. Some of the most intriguing areas of contemporary chemistry draw their inspiration from natural processes, and focus on both understanding and mimicking these phenomena. Atmospheric photochemistry plays an important role in climate change and air pollution, and a better understanding of this chemistry will help us to mitigate their negative effects. Photovoltaic cells capture solar energy and convert it into useful energy in much the same way that plants do through photosynthesis. Photochemical reactions are being harnessed for a wide range of interfacial chemistry, from the degradation of pollutants to the splitting of water to store energy. Light continues to play a critical role in the advancement of technologies that are giving us an understanding of chemistry at an incredibly small distance scale. Take, for instance, the 2014 Nobel Prize in Chemistry, which was awarded for the development of single-molecule spectroscopy (SMS), stimulated emission depletion (commonly known as STED) microscopy, and photoactivated localization microscopy (commonly known as PALM), techniques in which light emitted from molecules allows us to study samples with a spatial resolution that could not even have been dreamed of a mere 50 years ago. SMS is now being used in hundreds of laboratories worldwide to provide an unprecedented view of chemical, physical, and biological processes one molecule at a time. This technique is revolutionizing our understanding of phenomena ranging from chemical catalysis to the folding and unfolding of proteins. Similar ideas are now being explored for the spatial patterning of chemistry, which may enable us to extend the run of Moore’s Law for an additional decade or more. By the same token, chemistry is facilitating the development of light-based technologies. For instance, the 2014 Nobel Prize in Physics was awarded for the development of blue lightemitting diodes (LEDs). Advances in chemical vapor deposition were a crucial element in the creation of these devices, which are an enabling technology for highly energy efficient light bulbs and displays. Although the electric car is probably the best-known application of efficient, rechargeable batteries, these energy-storage devices are also making a major impact in light-based technologies for the developing world. In conjunction with white LEDs and photovoltaic cells, rechargeable batteries have made it possible to create low-cost lamps that can replace kerosene lamps in the developing world, improving health, allowing children to do their school work after dark, and contributing to nighttime safety in remote villages.
n December 20, 2013, the United Nations General Assembly voted to declare 2015 the International Year of Light and Light-Related Technologies (IYL for short). In January of 2015, a kick-off ceremony for IYL was held at UNESCO headquarters in Paris, the City of Light (Figure 1). This event celebrated the role of light not merely in science and engineering, but also in the arts, architecture, religion, and virtually every other aspect of our lives. The ceremony also highlighted the role that advances in light technology are playing in improving the quality of human life throughout the developing world. This Viewpoint is a call to action for us as chemists to celebrate the central role that light has played in the history of chemistry and the things that our discipline can do (and is doing) to help the world harness light more efficiently and effectively. As the school year begins in the United States and elsewhere, it is an ideal time to take advantage of the connections between chemistry and light, and the IYL resources that have been developed to help share these and other concepts involving light, to generate new excitement in our classrooms and beyond. The world is our classroom. It includes the lecture hall, the research laboratory, the seminar room, and the professional meeting. But it also includes our children’s schools, the media, our neighbors, and everyone else with whom we interact. Humankind exists due to the synergy between chemistry and light, and this relationship continues to have an enormous impact on the ongoing evolution of the way we live. IYL therefore provides us with a unique opportunity to promote chemistry, and science in general, in a manner to which every audience can relate. Below, we provide a few examples of the interrelation between chemistry and light that can be used as launching points for activities such as lectures, discussions in the grocery store, and even interviews with the media. Light-based phenomena have long inspired us as physical scientists. Phenomena such as the discrete absorption and emission spectra of atoms and molecules and the energies of electrons ejected from metals by light spurred the development of quantum mechanics, which has revolutionized our understanding of chemistry. Optical experiments in the visible region of the spectrum and beyond launched us on the path toward much of our current understanding of the structure and properties of atoms and molecules and continue to drive new discoveries in this area that will shape our understanding into the foreseeable future. Optical techniques have also allowed us to exert control over chemical processes, for instance, by causing a reaction to favor a particular desired product. The development of new spectroscopic methods is allowing us to study exotic species, transition states, and unexplored energy surfaces. Sophisticated nonlinear optical techniques are leading to remarkable new insights into chemical, biological, and materials systems. Chemists have long been fascinated with the manner in which Nature has harnessed light to facilitate chemistry throughout the history of our planet. Photochemistry plays a © 2015 American Chemical Society
Published: October 1, 2015 3882
DOI: 10.1021/acs.jpclett.5b01842 J. Phys. Chem. Lett. 2015, 6, 3882−3883
Viewpoint
The Journal of Physical Chemistry Letters
Figure 1. Eiffel Tower, as seen from UNESCO headquarters at the kick-off ceremony for the International Year of Light and Light-Based Technologies (photo by Amy S. Mullin).
The examples above are merely the tip of the iceberg. There are thousands of other means through which light plays an important role in chemistry and in which chemistry plays an important role in light-based technologies. The IYL has spurred the creation of numerous resources for explaining light-related phenomena, many of which are available at http://www. light2015.org/Home/HandsOnInvolvement.html. We urge all the readers of this Journal, and all chemists in general, to take advantage of the educational opportunities provided by IYL, not only in the remainder of 2015 but also beyond. Fiat lux!
Amy S. Mullin* John T. Fourkas*
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Department of Chemistry & Biochemistry University of Maryland, College Park, Maryland 20742, United States
AUTHOR INFORMATION
Corresponding Authors
* E-mail:
[email protected]. *E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
3883
DOI: 10.1021/acs.jpclett.5b01842 J. Phys. Chem. Lett. 2015, 6, 3882−3883
