Design and manufacturing of large area, thick cBN films Peter X. Feng (University of Puerto Rico), DMR 0706147.
With the support of the DMR, the researches are taking an integrative experimental and theoretical approach to develop a new technique for the fabrication of new boron nitride (BN) ceramic protective coatings over large areas. A super-short-pulse laser‑produced plasma (SSP‑LPP) deposition technique combined with a novel line-focusing technique is employed. The hardness of the cBN films more than 35 GPa (35000 N/mm2) have been obtained.
SEM and TEM images of BCNTs grown by SSP‑LPP.
They have also successfully used the new YAG laser SSP-LPP deposition technique for the mass production of boron nitride nanotubes (BCNT). Structural and electrochemical properties of BCNT samples were studied. The corresponding invention disclosure on the new technique is being submitted to the UPR Intellectual Property Office. More recently, the BCNTs were also tested for rechargeable battery electrode applications. Electrochemical testing showed that the BCNT electrodes can deliver a reversible capacity of 205 Ahcm-2m-1 in Li-ion cells, which is higher than the theoretical capacity of graphite electrodes, commonly used in commercial batteries.
Besides teaching, the researchers also spent a significant part of their time with both graduate and undergraduate students in the research laboratory. The research group conducts group weekly meetings and seminars to discuss problems and solutions on experiments and researches. The emphasis throughout these sessions is on “learning from each other and helping one another”. Currently, a total of six undergraduate students, and nine doctoral students participate in their laboratories.
Educational visit and talk to the UPR elementary school with the participation of graduate students.
As members of Puerto Rico NSF-EPSCoR / Institute for Functional Nanomaterials (IFN), Feng and Morell have also been working together with the IFN education component, and make education contributions to the IFN-NSF Nanoscale Center for Learning and Teaching partnership. For example, Feng, Morell and their doctoral students participate in a one-week summer activity organized by IFN for high school students and teachers. Feng, Morell and their doctoral students also visited UPR elementary school twice to give talks and demonstrations that illustrate basic concepts of physical sciences.