title: Chemical enhancement by nanomaterials under X-ray irradiation.
abstract: We report here a new phenomenon of dynamic enhancement of chemical reactions by nanomaterials under hard X-ray irradiation. The nanomaterials were gold and platinum nanoparticles, and the chemical reaction employed was the hydroxylation of coumarin carboxylic acid. The reaction yield was enhanced 2000 times over that predicted on the basis of the absorption of X-rays only by the nanoparticles, and the enhancement was found for the first time to depend on the X-ray dose rate. The maximum turnover frequency was measured at 1 × 10(-4) s(-1) Gy(-1). We call this process chemical enhancement, which is defined as the increased yield of a chemical reaction due to the chemical properties of the added materials. The chemical enhancement described here is believed to be ubiquitous and may significantly alter the outcome of chemical reactions under X-ray irradiation with the assistance of nanomaterials.
authors.affiliation: Department of Chemistry, University of California, Davis, California 95616, USA.
authors.forename: Neal N
authors.initials: NN
authors.lastname: Cheng
authors.forename: Zane
authors.initials: Z
authors.lastname: Starkewolf
authors.forename: R Andrew
authors.initials: RA
authors.lastname: Davidson
authors.forename: Arjun
authors.initials: A
authors.lastname: Sharmah
authors.forename: Changju
authors.initials: C
authors.lastname: Lee
authors.forename: Jennifer
authors.initials: J
authors.lastname: Lien
authors.forename: Ting
authors.initials: T
authors.lastname: Guo
mesh_terms: D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties; D014965:X-Rays
chemical_list: D010984:Platinum; D006046:Gold