title: Anisotropic Molecular Ionization at 1 V from Tellurium Nanowires (Te NWs).
abstract: Ionization of molecular species from one-dimensional (1D) tellurium nanowires (Te NWs) has been achieved at 1 V. Molecules with a range of chemical functional groups gave quality mass spectra with high signal/noise ratios and no fragment ions. Experiments suggest the possibility of emission of microdroplets of solution due to the intense fields at the ends or interfaces of nanostructures. It appears that electrolytic conduction of the solution wetting of the nanostructures and not the electronic conduction of the nanostructures themselves is involved in the ionization event. Anisotropy was seen when two-dimensionally aligned Te NWs were used for ionization. The orientation effect of aligned Te NWs on molecular ion intensity is demonstrated for many analytes including organic molecules and amino acids with experiments done using a silicon substrate having aligned Te NWs. These measurements suggest the possibility of creating a MS source that extends the applicability of mass spectrometry. Analysis of a variety of analytes, including amino acids, pesticides, and drugs, in pure form and in complex mixtures, is reported. These experiments suggest that 1D nanostructures in general could be excellent ionization sources.
authors.affiliation: DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India.
authors.forename: Rahul
authors.initials: R
authors.lastname: Narayanan
authors.affiliation: DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India.
authors.forename: Depanjan
authors.initials: D
authors.lastname: Sarkar
authors.affiliation: DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India.
authors.forename: Anirban
authors.initials: A
authors.lastname: Som
authors.affiliation: Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Wleklinski
authors.affiliation: DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India.|Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: R Graham
authors.initials: RG
authors.lastname: Cooks
authors.affiliation: DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology Madras , Chennai 600036, India.
authors.forename: Thalappil
authors.initials: T
authors.lastname: Pradeep