2008 Spring Symposium

 
Mosha Zhao¹, D. Li², J. Gar­ra², D. A. Bon­nell², J. M. Vohs^1
1Depart­ment of Chem­i­cal and Bio­mol­e­c­u­lar Engi­neer­ing
²Depart­ment of Mate­ri­als Sci­ence and Engi­neer­ing
Uni­ver­si­ty of Penn­syl­va­nia
Philadel­phia, PA 19104

Abstract — The abil­i­ty to manip­u­late the ori­en­ta­tion of the dipoles in fer­ro­elec­tric ceram­ic­sh­olds promise as a method to tai­lor the sur­face reac­tiv­i­ty of these mate­ri­als for speci­f­i­cap­pli­ca­tions. While over the last 50 years mul­ti­ple stud­ies have sug­gest­ed that the ori­en­ta­tionof fer­ro­elec­tric domains may affect the ener­get­ics of adsorp­tion on fer­ro­elec­tric oxides,definitive evi­dence is still lack­ing. In this talk we will present the first unam­bigu­ousob­ser­va­tions of dif­fer­ences in the ener­get­ics of adsorp­tion on fer­ro­elec­tric domains forad­sorp­tion of methanol and ethanol on bar­i­um titanate. Domain-depen­dent stick­ing­co­ef­fi­cients are observed and indi­cate that the fer­ro­elec­tric ori­en­ta­tion alters the strength ofthe inter­ac­tion of adsorbed species with the sur­face. Addi­tion­al­ly, in ethanol TPD thedes­orp­tion peak shapes and the rel­a­tive prod­uct yields were found to be polar­iza­tion­de­pen­dent sug­gest­ing that fer­ro­elec­tric polar­iza­tion may also affect the intrin­sic reac­tiv­i­ty­of the sur­face.

Speaker’s Biog­ra­phy — Mosha Zhao is cur­rent­ly a PhD can­di­date of chem­i­cal and bio­mol­e­c­u­larengi­neer­ing in School of Engi­neer­ing and Applied Sci­ence (SEAS), Uni­ver­si­ty ofPenn­syl­va­nia. She is cur­rent­ly study­ing the fer­ro­elec­tric polar­iza­tion on sur­face reac­tion­ad­vised by Dr. John Vohs. She is the win­ner of the Catal­y­sis Club of Philadel­phia 2007student poster com­pe­ti­tion.