Wulff Lecture focuses on the history and future of glass

Raise a glass—to glass! Pennsylvania State University’s John C Mauro marked the United Nations International Year of Glass 2022 with a talk celebrating the long history and exploring the promising future of one of humankind’s most important materials. 
 
It’s in the windows that provide natural light. The eyeglasses that improve vision. The telescopes that deliver astounding images from space. And the optical fibers crossing the globe.
 
“This is what made the internet possible,” said Mauro, who was at MIT on Nov. 4. “This is what brought us into the Information Age, and behind the scenes there it’s all glass.”
 
The Dorothy Pate Enright Professor and Associate Head for Graduate Education in Penn State’s Department of Materials Science and Engineering was the speaker for DMSE’s twice-yearly Wulff Lecture, a general-audience lecture series designed to spark enthusiasm in materials science and engineering.
 
Mauro, who worked for Corning for 18 years before moving to academia, is a co-inventor of Gorilla Glass, the chemically strengthened, damage-resistant glass that protects smartphones from scratches and falls. He was also one of the influencers behind the International Year of Glass, which was adopted by the United Nations General Assembly to acknowledge the material’s outsized role in human society. 
 
In his video-recorded talk, Mauro discussed past glassmaking—reading from a 3,300-year-old notebook on how to make glass. “‘On the day when you plan to place the glass in the kiln, you make a sheep sacrifice.’” As chuckles arose in the audience, Mauro explained that the reading makes the point that glassmaking is a sensitive process, depending on the choice of raw materials and the purity of those materials.
 
“They didn’t have x-ray diffraction back then,” Mauro said, referring to the material-analyzing technique. “What they would see is sometimes it seemed to work, and sometimes it didn’t work.”
 
Mauro also looked to the future, to opportunities that glass can offer in electronic devices, computing, health care, and more. He pointed to state-of-the-art phones with flexible glass displays, glasses for data storage that can last much longer than traditional magnetic memory storage, and bioactive glass fibers that can stimulate the body’s healing process and repair ulcers.
 
A downside of producing glass is a massive carbon footprint, Mauro said. The global glass industry produces approximately 86 million tons of carbon dioxide a year. Most of that is because of the energy required to melt glass; a smaller portion of carbon emissions is from the decomposition of the raw materials, or carbonate batch materials, in soda-lime-silica glass, the common form of glass, used for windowpanes and bottles.
 
To address the problem, Mauro’s research group at Penn State has developed LionGlass, a patent-pending family of glasses that reduces melting and forming temperatures by 350 degrees Celsius. 
 
“And it’s made from a chemistry that also, in parallel, eliminates the need for carbonate batch materials,” Mauro said. “So that part of the carbon emission is eliminated; the other part is greatly reduced.”