A spontaneous collaboration

In 2007, when Oak Ridge National Laboratory (ORNL) researchers calculated that adding boron would bend carbon nanotubes, they did little with the information.

Boron was one of several elements the computational scientists plugged into their model as they investigated ways to induce useful changes in nanotube structures. There were experiments to compare with the results of most of their calculations. There weren’t any to check against the boron-doped nanotube simulations.

“We didn’t think anything about boron, really,” says Bobby Sumpter, Chemical and Materials Sciences Group leader and director of ORNL’s Nanomaterials Theory Institute. “We thought it was interesting how it preferred negative curvature, and we kind of just left it at that.”

Then Humberto Terrones, an ORNL-affiliated researcher from Belgium’s Université Catholique de Louvain, came to visit last year. He and his brother, Mauricio, of Pennsylvania State University and Japan’s Shinshu University, were investigating new nanotube materials.

Humberto Terrones “was talking about how they’d observed these three-dimensional-looking structures when they doped boron in,” Sumpter recalls. “I said, ‘But, Humberto, remember our results? Where we found these interesting effects and we think we understand exactly what happens?’ I hadn’t realized they’d done experiments for boron and just learned about it over a casual discussion – which actually turn out to be usually the most productive scientific discussions – just a cup of coffee with a white board.”

Sumpter and Vincent Meunier of Rensselaer Polytechnic Institute recalculated the boron results and published them jointly with Rice University doctoral student Daniel Hashim’s discovery of three-dimensional, macro-scale nanosponges. “It’s always good to have experimental evidence that backs up theory or vice versa,” Hashim says. “In this case we made the theory and the experimental evidence together and it gave this paper a lot more impact.”