MASARYK UNIVERSITY Faculty of Science Czech Republic MALDI and LDI Mass Spectrometry of Solids Sachinkumar Dagurao Pangavhane Doctoral Thesis Director: Prof. RNDr. Josef Havel, DrSc. September 2012 Bibliographic identification Author’s name Sachinkumar Dagurao Pangavhane Director Prof. RNDr. Josef Havel, DrSc. Thesis title MALDI and LDI Mass Spectrometry of Solids Study program PřF D-CH4 Chemistry Study domain Analytical Chemistry Year of defense 2012 Keywords LDI/MALDI TOF MS, clusters, binary/ternary/multi-component chalcogenide glasses, phosphorus nitride, clusters structure 2 Copyright © 2012 by Sachinkumar D. Pangavhane All Rights Reserved, Masaryk University 3 Declaration of authenticity I declare that all material presented in this thesis is my own investigation, except where otherwise stated or fully acknowledged wherever references adapted from other sources. Brno, September 2012 Sachinkumar D. Pangavhane 4 Cordial reverence I feel very deeply my cordial reverence to my mother Mrs. RATNAMALA DAGURAO PANGAVHANE and my father Mr. DAGURAO KASHINATH PANGAVHANE for their blessings and love, plus I’m thankful to my siblings for their support and love during my abroad stay. Eyes afraid, hands work! - My mother 5 Acknowledgments Foremost, I owe an immense gratitude for director of this thesis, Prof. Josef Havel; his substantial comments, insightful criticisms, and dense spirit during discussion as to fight against ‘why and what?’ are profoundly honoured. I would like to thank Prof. Petr Němec and Prof. Tomáš Wagner from Centre for Material Science, and Department of General and Inorganic Chemistry and Research Centre, Faculty of Chemical Technology, University of Pardubice (Pardubice, Czech Republic), for their steadfast support in the preparation of glass samples. I would also like to thank Prof. Manuel Valiente, Director, Group of Separation Techniques, Department of Chemistry, University Autònoma of Barcelona (Barcelona, Spain) for his collaboration. 6 Abstract PhD thesis deals with identification of clusters generated using UV laser (337 nm) from solids. Mass spectra were measured with TOF MS. First of all chalcogenide glasses and their nano-layers were studied. Further, the clusters formed by laser desorption of phosphorus nitride (P3N5) were investigated while clusters stoichiometry was determined via isotopic envelope analysis and computer modeling. Main part of PhD thesis deals with mass spectrometric study of binary (As-Se), ternary (As-S- Se) and Er (III) doped multicomponent (Ga-Ge-Sb-S) chalcogenide glasses in bulk form but also in the form of nano-layers prepared by pulsed laser deposition technique. Several combinations of chalcogenide glasses of different composition (binary, ternary and quaternary systems) were studied. Clusters structure observed in plasma indicates structural motifs of glasses and yields fundamental information on glass structure. The results obtained were completed with Raman spectroscopy. Technique of clusters analysis was also applied to other compounds like phosphorus nitride, which is used in electronics. The P3N5 compound is stable solid. The aim was to evaluate possibility to detect high nitrogen clusters (proposed as fuel of future). It was partially successful, in addition to numerous P-N clusters; the formation of high nitrogen clusters up to N15 was proved. 7 Abstrakt (in Czech) PhD Disertace se zabývá určením stechiometrie klastrů generovaných UV laserem (337 nm) z pevných látek. Hmotnostní spektra byla měřena v režimu TOF. Především byla studována chalkogenidová skla a jejich nano-vrstvy, dále pak klastry vznikající laserovou desorpcí a ionisací nitridu fosforu (P3N5). Stechiometrie klastrů byla určována analysou isotopových obálek a počítačovým modelováním. Hlavní náplní distertace je hmotnostní spektrometrie binárních (As-Se), ternárních (As-S-Se) a Er (III) dopovaných vícesložkových chalkogenidových skel (Ga-Ge-Sb-S) v makro formě ale také ve formě nano-vrstev deponovaných pulsní laserovou deposicí. Bzlo studováno několik kombinací chalkogenidových skel o různém složení (binární, ternární a kvarterní systémy). Struktura klastrů pozorovaných v plasmatu odráží do jisté miry chemické strukturní motivy skel a podává tak fundamentální informaci o struktuře skel. Výsledky byly doplněny Ramanovou spektrometrií. Technika klastrové analýzy byla aplikována také na analýzu klastrů tvořených z nitridu fosforu, sloučeniny hojně používané v elektronice. Sloučenina P3N5 je stabilní látkou v pevné fromě. Cílem bylo vyhodnotit možnosti tvorby vysokých dusíkových klastrů (navrhovaných jako palivo budoucnosti). Výsledky jsou částečně úspěchem, kromě četných P-N klastrů byla potvrzena tvorba vysokých dusíkových klastrů – až do N15. 8 Content Bibliographic identification…………………………………………………………………….....2 Copyright……………………………………………………………………………………….....3 Declaration of authenticity………………………………………………………………………...4 Cordial reverence……………………………………………………………………………….....5 Acknowledgments…………………………………………………………………………..…......6 Abstract ……………………….…………………………………………………………..……....7 Abstrakt (in Czech)…………………………………………………………..................................8 Content…………………………………………………………………………….........................9 Chapter 1. INTRODUCTION…………………………………………………………….……...12 1.1 Chalcogenide glasses….………………………………………………..............12 1.2 Phosphorus nitride…….………………………………………………..............14 Aims of Thesis……..………………………………………………………………………….....16 Chapter 2. MASS SPECTROMETRY………………………………………………………......17 2.1 Introduction……………………………………………………………………..17 2.2 Instrumentation………………………………………………………................17 2.3 Brief History…………………………………………………………………....18 Chapter 3. MALDI TOF MS…………………………………………………………………….20 3.1 Introduction……………………………………………………………………..20 3.2 Principle………………………………………………………………………...21 3.3 Sample Preparation……………………………………………………………..22 3.4 Calibration………………………………………………………………………24 3.5 Instrumentation………………………………………………………………....25 3.5.1 Ionization chamber………………………………………………………..25 3.5.2 Mass analyzer……………………………………………………………..26 3.5.3 Detector…………………………………………………………………...28 3.6 Delayed extraction……………………………………………………………...29 3.7 Post source decay…………………………………………………………….....29 3.8 Isotopic envelope…………………………………………………………….....29 3.9 Cluster ion………………………………………………………………………30 Chapter 4. EXPERIMENTAL…………………..……………………………………………….31 4.1 Chemicals & apparatus………………………………………………………....31 4.1.1 Binary As-Se glasses………....………………………………………......31 4.1.2 Ternary As-S-Se glasses………………………….........................………31 4.1.3 Multi-component Erbium doped Ga-Ge-Sb-S glasses…………………...31 4.1.4 Phosphorus nitride P3N5 …………………………………………………32 9 4.2 Sample preparation…………………………………………………………......32 4.2.1 Binary As-Se glasses…………………………………………………......32 4.2.2 Ternary As-S-Se glasses….…………………………………....................32 4.2.3 Multi-component Erbium doped Ga-Ge-Sb-S glasses……………….......33 4.2.4 Phosphorus nitride P3N5 …………………………………………………34 4.3 Instrumentation…………………………………………………………………34 4.3.1 Binary As-Se glasses…………………………………………………......34 4.3.2 Ternary As-S-Se glasses….………………………………........................35 4.3.3 Multi-component Erbium doped Ga-Ge-Sb-S glasses……………….......35 4.3.4 Phosphorus nitride P3N5 …………………………………………………36 4.4 Software & computation………………………………………………………..37 Chapter 5. RESULTS AND DISCUSSION…………………………………………………......38 5.1 Binary glasses As-Se…………………………………………………................38 5.1.1 Effect of laser energy………………………………………………….....38 5.1.2 Positive ion mode………………………………………………………...39 5.1.3 Negative ion mode…….…………………………………….....................40 5.1.4 Raman scattering of As-Se bulk glasses…………….…………………....42 5.1.5 Structure of AspSeq clusters and of As-Se glasses…………………..........44 5.2 Ternary glasses As-S-Se……………………………………………………......47 5.2.1 Negative ion mode………………………………………….....................47 5.2.2 Positive ion mode………………………………………………………..49 5.2.3 Analysis of nano-layers………………………………………………….52 5.2.4 Structure of binary and ternary clusters………………..…………….......53 3+ 5.3 Rare earth (Er ) doped quaternary glasses Ga-Ge-Sb-S …………………....…54 5.3.1 Chemical composition and amorphous state of prepared samples………54 5.3.2 Glass structure supported by Raman analysis……………………………55 5.3.3 Mass spectrometry.....................................................................................56 5.3.4 Effect of laser energy…………………………………………………….57 5.3.5 Positive ion mode.......................................................................................58 5.3.6 Negative ion mode.....................................................................................61 5.3.7 Germanium species and relationship with Hydrogen……………………65 5.3.8 Comparison of glass structure and identified clusters…………………...66 5.4 Phosphorus nitride P3N5 ………………………………………..………………67 5.4.1 LDI of P3N5 …...………………………………………..…………….....68 5.4.2 MALDI of P3N5 ………………………………………...….....................71 5.4.3 Stoichiometry of clusters and the crystal structure of solid P3N5 ….…....74 5.5 Publications……………………………………………………………...……...76 10 Chapter 6. CONCLUSIONS……………………………………………………………...…….110 6.1 As-Se glasses.....................................................................................................110 6.2 As-S-Se glasses..................................................................................................111 6.3 Ga-Ge-Sb-S glasses...........................................................................................111 6.4 Phosphorus nitride…………………………………………………………….112 6.5 General conclusions…..………………………………………………………112 6.6 Obecné závěry (in Czech)..................................................................................113