Undergraduates at UPR-Humacao taking their research

1. Gas sensors using electrospun conducting polymer nanofibersNicholas J. Pinto (University of Puerto Rico – Humacao) DMR 0703544 Electrospun isolated camphor sulfonic acid doped polyaniline nanofiber sensors were fabricated and tested in the presence of various aliphatic alcohol vapors. Due to the large surface to volume ratio, uniform diameter and small quantity of active material used in the construction, these sensors are comparable to or faster than those prepared from nanofiber mats of the same polymer. Sensors made from individual fibers exhibit larger responses, especially for bigger alcohol molecules, and also show true saturation upon exposure and removal of the alcohol vapor enhancing their reliability. A faster response and the ability to selectively deposit isolated nanofibers using electrospinning makes this technique attractive in the fabrication of low cost and low power consumption rapid response reliable sensors1. Figure 1: Normalized resistance of individual electrospun HCSA doped polyaniline nanofibers to various alcohols. (a) Methanol (□) (b) Ethanol (○) (c) 2-propanol (∆). The response is faster than sensors made from cast films. 1. Electric response of isolated electrospun polyaniline nanofibers to vapors of aliphatic alcohols, N.J. Pinto, I. Ramos, R. Rojas, P-C. Wang, A.T. Johnson, Jr., Sens. Actuators B129, 621-627 (2008).

2. Undergraduates at UPR-Humacao taking their research outside Puerto RicoNicholas J. Pinto (University of Puerto Rico – Humacao) DMR 0703544 Rut at the summer 2008 REU program at MIT Two undergraduates students are currently in NSF-REU programs this summer at MIT (Rut Rivera) and at UPENN (Maria Abreu). Another undergraduate (Richard Rojas) has accepted graduate studies at U. Wisconsin-Madison starting in Fall 2008. All are minority students. Pinto has written two manuscripts on new experiments that are taught at UPR-Humacao in the senior lab course and that can be implemented at other Institutions2,3. 2. Two experiments in physics based on electrospun polymer nanofibers, N.J. Pinto, Am. J. Phys. (in print) 3. Integration of nanoscience into the undergraduate curriculum via simple experiments based on electrospun polymer nanofibers, N.J. Pinto, (ACS symposium Books on Nanotechnology- in print) Richard with his poster at the ANM2008 scientific conference in Portugal Maria with her poster at the 2008 APS meeting in New Orleans