title: Flash ignition of freestanding porous silicon films: effects of film thickness and porosity.
abstract: We report the first successful xenon flash ignition of freestanding porous Si films in air. The minimum flash ignition energy (Emin) first decreases and then increases with increasing the porous Si film thickness due to the competition between light absorption and heat loss. The Emin is lower for higher porosity film because high porosity reduces both the heat capacity and the thermal conductivity, facilitating the temperature rise. These results are important for initiating controlled porous Si combustion and preventing their unwanted combustion for safety reasons.
authors.affiliation: Department of Mechanical Engineering, Stanford University , Stanford, California 94305, United States.
authors.forename: Yuma
authors.initials: Y
authors.lastname: Ohkura
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Weisse
authors.forename: Lili
authors.initials: L
authors.lastname: Cai
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Zheng
mesh_terms: D006358:Hot Temperature; D008027:Light; D049329:Nanostructures / Q000737:chemistry*; D016062:Porosity; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties; D013814:Thermal Conductivity; D014978:Xenon / Q000737:chemistry*
chemical_list: D014978:Xenon; D012825:Silicon