Researchers Use 3D Printing to Potentially Produce Graphene in Bulk Quantities

Graphene is a material that has generated a lot of excitement, in the 3D printing industry and beyond. It’s over 100 times stronger than steel, it’s lightweight, and it’s a great conductor of electricity and heat. The only problem with graphene, it seems, is that it’s difficult to produce in bulk – or at least it has been so far. Researchers at Rice University and Tianjin University are working to change that, and they’ve broken some ground by 3D printing atomically thin graphene in centimeter-sized pieces.

The research was documented in a paper entitled “Three-Dimensional Printed Graphene Foams,” which you can access here. It could potentially lead to the bulk production of graphene in amounts useful for industrial applications.

“This study is a first of its kind,” said Rice chemist James Tour, co-corresponding author of the paper. “We have shown how to make 3-D graphene foams from nongraphene starting materials, and the method lends itself to being scaled to graphene foams for additive manufacturing applications with pore-size control.”

Back in 2016, researchers in Tour’s lab began making graphene foam using nickel, lasers and, of all things, powdered sugar. This year, they furthered their research by reinforcing the foam with carbon nanotubes, producing a material that they called “rebar graphene.” Rebar graphene was strong enough to support 3,000 times its own weight while maintaining its shape. It was difficult to make, however, requiring a prefabricated 3D mold, a 1,000ºC chemical vapor deposition process and almost three hours of heating and cooling.

Now, though, Tour’s lab, along with two other labs from Rice and Tianjin Universities, has come up with a new process for producing the material: 3D printing. Using nickel and powdered sugar, the researchers adapted a laser-based 3D printing technique to create small blocks of graphene foam. No molds are required, and the process can be conducted at room temperature.

“This simple and efficient method does away with the need for both cold-press molds and high-temperature CVD treatment,” said co-lead author Junwei Sha, a former student in Tour’s lab who is now a postdoctoral researcher at Tianjin. “We should also be able to use this process to produce specific types of graphene foam like 3-D printed rebar graphene as well as both nitrogen- and sulfur-doped graphene foam by changing the precursor powders.”

The researchers used a commercially available CO₂ laser to melt the sugar, while the nickel acted as a catalyst, forming graphene after the mixture cooled. They conducted an extensive study to determine the optimal amount of time and laser power to maximize the production of graphene. The result was a lightweight, low-density graphene with large pores that make up 99 percent of its volume.

“The 3-D graphene foams prepared by our method show promise for applications that require rapid prototyping and manufacturing of 3-D carbon materials, including energy storage, damping and sound absorption,” said co-lead author Yilun Li, a graduate student at Rice.

Authors of the study include Junwei Sha, Yilun Li, Rodrigo Villegas Salvatierra, Tuo Wang, Pei Dong, Yongsung Ji, Seoung-Ki Lee, Chenhao Zhang, Jibo Zhang, Robert H. Smith, Pulickel M. Ajayan, Jun Lou, Naiqin Zhao, and James M. Tour. Discuss in the 3D Printed Graphene forum at 3DPB.com.

[Source: Rice University]