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An interfacial engineering approach towards two-dimensional porous carbon hybrids for high performance energy storage and conversionLu, Chenbao, Liu, Shaohua, Zhang, Fan, Su, Yuezeng, Zou, Xiaoxin, Shi, Zhan, Li, Guodong, Zhuang, Xiaodong 17 July 2017 (has links)
In order to improve the performance and fundamental understanding of conducting polymers, development of new nanotechnologies for engineering aggregated states and morphologies is one of the central focuses for conducting polymers. In this work, we demonstrated an interfacial engineering method for the rational synthesis of a two-dimensional (2D) polyaniline (PANI) nano-array and its corresponding nitrogen-doped porous carbon nanosheets. Not only was it easy to produce a sandwich-like 2D morphology, but also the thickness, anchored ions and produced various metal phosphides were easily and rationally engineered by controlling the composition of the aqueous layer. The novel structural features of these hybrids enabled outstanding electrochemical capacitor performance. The specific capacitance of the as-produced diiron phosphide embedded nitrogen-doped porous carbon nanosheets was calculated to be as high as 1098 F g−1 at 1 A g−1 and an extremely high specific capacitance of 611 F g−1 at 10 A g−1, outperforming state-of-the-art performance among porous carbon and metal-phosphide-based supercapacitors. We believe that this interfacial approach can be extended to the controllable synthesis of various 2D material coupled sandwich-like hybrid materials with potential applications in a wide range of areas.
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Polyacrylonitrile-based Hierarchical Porous Carbons for SupercapacitorsZhu, Shijin 19 September 2022 (has links)
The globally increasing energy demand that results from the rapid development of modern society has created intensive attention towards the importance of energy efficiency. The areas of energy storage and energy conversion have become one of the most important topics in scientific community at present. As new generation energy storage elements, supercapacitors have exhibited promising practical prospects in the information, transportation, electronics and other sectors due to their charge and discharge performance at high rate, high power density as well as long cycle life. Energy density, including gravimetric energy density, areal energy density and volumetric energy density, is one of the most critical indicator evaluating the performance of supercapacitors. The electrochemical performance of supercapacitors depends mainly on the electrochemical activities and kinetic properties of electrode materials. Carbonaceous materials are deemed to be highly promising, and therefore are extensively investigated energy storage materials for supercapacitors because of their environmental friendliness, low-cost production and outstanding chemical inertness during charging-discharging processes. The specific surface area has been long thought to be the main factor influencing the capacitance of carbonaceous materials. However, the pore structure is of similar importance. High specific surface areas are always arising from a high content of micropores. However, pore radii in the sub-nanometer range impede the ionic charge transfer ability significantly and thus cause a damping of capacitance.
In this thesis, hierarchical porous carbons and their composite materials were fabricated by using polyacrylonitrile as carbon precursor for a tailored step-by-step pore forming method, including phase inversion, CaCO3 activation and KOH activation. The materials were thoroughly characterized by XRD, SEM, TEM, BET, XPS and Raman spectroscopy to ascertain the chemical and structural features. The electrochemical properties were studied by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) in detail to analyze the pore effect, which strongly influence their electrochemical properties.
Porous carbons with high specific surface areas up to 2315 m2 g-1 and high pore volume of 1.9 cm3·g-1 were prepared. A step-wise pore forming method was employed to ensure a high specific surface area and high content of macro/mesopore at the same time. The relationship between pore structure, electrochemical capacitance and rate capability was investigated by changing the content of micropores. For a same specific surface area, a higher micropore content led to a lower capacitance and poorer rate capability. Based on these results, the capacitance was optimized to be 286.8 F g-1.
The areal energy density of the supercapacitors can be improved by increasing the mass loading in a certain area directly. However, insufficient electrochemical reaction may be caused by a lack of unhindered electrical and ionic charge transfer routes, resulting in inefficient material utilization. This problem is addressed by designing hierarchical pore structures with embedded conductive additives. Thus, hierarchical porous carbons were modified by embedding carbon nanotubes (CNTs), followed by coverage with thin layers of birnessite. Owing to the hierarchical pore design and the very high pore volume, the birnessite coverage did not cause pore blocking. At the same time, an intimate contact between carbon and birnessite was established. A high area energy density of 627.8 μWh·cm-2 was obtained based on an optimized mass loading of 13.9 mg cm-2.
The volumetric energy density of supercapacitors was determined by the density and porosity of active materials. Similarly, the dense active materials not always generate high specific capacitance because of an increased dead mass. However, too porous active materials do not provide sufficient volumetric capacitance due to a waste of space. Thus, density and porosity must be balanced by hierarchical pore structure design so that all pores are interconnected and can be accessed by ions. At the same time, the content of these pores should be as low as possible to save space. Based on the results, highly hierarchical porous carbons were synthesized and embedded into conductive carbon foam to combine electronic conductivity with ionic transfer. In that way, a volumetric energy density as high as 19.44 µWh cm-3 at a volumetric power density of 500 mW cm-3 was generated.
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Experimental and theoretical studies on germanium-containing precursors for twin polymerization / Experimentelle und theoretische Untersuchungen an germaniumhaltigen Präkursoren für die ZwillingspolymerisationKitschke, Philipp 24 June 2016 (has links) (PDF)
Im Fokus dieser Arbeit standen zwei Ziele. Zum einem war es Forschungsgegenstand, dass Konzept der Zwillingspolymerisation auf germaniumhaltige, molekulare Vorstufen wie zum Beispiel Germylene, spirozyklische Germaniumverbindungen und molekulare Germanate zu erweitern und somit organisch-anorganische Komposite beziehungsweise Hybridmaterialien darzustellen. Dazu wurden neuartige Germaniumalkoxide auf der Basis von Benzylalkoholaten, Salicylalkoholaten sowie Benzylthiolaten synthetisiert, charakterisiert und auf ihre Fähigkeit Komposite beziehungsweise Hybridmaterialien über den Prozess der Zwillingspolymerisation zu erhalten studiert.
Ein zweites Ziel dieser Arbeit war es, Beziehungen zwischen der Struktur und der Reaktivität dieser molekularen Vorstufen sowie deren Einfluss auf die Eigenschaften der erhaltenen Polymerisationsprodukte zu identifizieren und systematisch zu untersuchen. Hierfür wurden zum einen verschiedene Substituenten, welche unterschiedliche elektronische sowie sterische Eigenschaften aufweisen, an den aromatischen Einheiten der molekularen Vorstufen eingeführt. Die Effekte der Substituenten auf den Prozess der Zwillingspolymerisation und auf die Eigenschaften der Komposite beziehungsweise Hybridmaterialien wurden für die Verbindungsklasse der Germanium(II)salicylalkoholate, der molekularen Germanate sowie der spiro-zyklischen Siliziumsalicylalkoholate untersucht. Spirozyklische Siliziumsalicylalkoholate, wie zum Beispiel 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin], wurden im Rahmen dieser Arbeit mit einbezogen, da sie aufgrund ihres nahezu idealen Zwillingspolymerisationsprozesses geeignete Modelverbindungen für Reaktivitätsstudien darstellen. Zudem wurde der Einfluss der Substituenten auf die Charakteristika der aus den Kompositen beziehungsweise Hybridmaterialien erhaltenen Folgeprodukte (poröse Kohlenstoffmaterialien und oxydische Materialien) studiert. Des Weiteren wurde eine Serie von spirozyklischen Germaniumthiolaten, welche isostrukturell zu 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin] sind, synthetisiert, um systematisch den Einfluss der Chalkogenide, Sauerstoff und Schwefel, in benzylständiger sowie phenylständiger Position auf deren Reaktionsvermögen im Polymerisationsprozess zu untersuchen.
Die experimentellen Ergebnisse zu den Struktur-Reaktivitätsbeziehungsstudien wurden, soweit es jeweils durchführbar war, mittels quantenchemische Rechnungen validiert und die daraus gezogenen Schlüsse in die Diskussion zur Interpretation der experimentellen Ergebnisse mit einbezogen.
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Investigation of electrochemical properties and performance of stimulation/sensing electrodes for pacemaker applicationsNorlin, Anna January 2005 (has links)
People suffering from certain types of arrhythmia may benefit from the implantation of a cardiac pacemaker. Pacemakers artificially stimulate the heart by applying short electrical pulses to the cardiac tissue to restore and maintain a steady heart rhythm. By adjusting the pulse delivery rate the heart is stimulated to beat at desired pace. The stimulation pulses are transferred from the pacemaker to the heart via an electrode, which is implanted into the cardiac tissue. Additionally, the electrode must also sense the cardiac response and transfer those signals back to the electronics in the pacemaker for processing. The communication between the electrode and the tissue takes place on the electrode/electrolyte (tissue) interface. This interface serves as the contact point where the electronic current in the electrode is converted to ionic currents capable to operate in the body. The stimulation/sensing signals are transferred across the interface via three electrochemical mechanisms: i) non-faradaic charging/discharging of the electrochemical double layer, ii) reversible and iii) irreversible faradaic reactions. It is necessary to study the contribution of each mechanism to the total charge transferred to evaluate the pacing/sensing performance of the pacemaker electrode. In this thesis, the electrochemical properties and performance of stimulation/sensing electrodes for pacemaker applications have been investigated by electrochemical impedance spectroscopy, cyclic voltammetry and transient electrochemical techniques. All measurements were performed in synthetic body fluid with buffer capacity. Complementary surface analysis was performed with scanning electron microscopy, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. The results reveal different interfacial behaviour and stability for electrode materials such as Pt, TiN, porous carbon, conducting oxides (RuO2 and IrO2 and mixed oxides) and porous Nb2O5 oxide. The influence of the charge/discharge rate on the electrode characteristics also has been evaluated. Although the rough and porous electrodes provide a high interfacial capacitance, the maximum capacitance cannot be fully employed at high charge/discharge rates because only a small part of the effective surface area is accessible. The benefit of pseudo-capacitive material properties on charge delivery was observed. However, these materials suffer similar limitations at high charge/discharge rate and, hence, are only utilising the surface bound pseudo-capacitive sites. Porous Nb2O5 electrodes were investigated to study the performance of capacitor electrodes. These electrodes predominantly deliver the charge via reversible non-faradaic mechanisms and hence do not produce irreversible by-products. They can deliver very high potential pulses while maintaining high impedance and, thus, charge lost by faradaic currents are kept low. By producing Nb oxide by plasma electrolysis oxidation a porous surface structure is obtained which has the potential to provide a biocompatible interface for cell adherence and growth. This thesis covers a multidisciplinary area. In an attempt to connect diverse fields, such as electrophysiology, materials science and electrochemistry, the first chapters have been attributed to explaining fundamental aspects of the respective fields. This thesis also reviews the current opinion of pacing and sensing theory, with special focus on some areas where detailed explanation is needed for the fundamental nature of electrostimulation/sensing. / QC 20101014
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Nanostrukturierter Kohlenstoff durch Zwillingspolymerisation an Hart-TemplatenBöttger-Hiller, Falko 13 September 2012 (has links)
Gegenstand der vorliegenden Arbeit ist die Herstellung von nanostrukturierten Kohlenstoffen. Die Synthese erfolgt dabei durch die Zwillingspolymerisation der siliziumhaltigen Zwillingsmonomere 2,2’Spirobi[4H-1,3,2-benzodioxasilin] sowie Tetrafurfuryloxysilan. Die entstehenden Nanokomposite werden anschließend carbonisiert und das SiO2-Netzwerk herausgelöst. Die Zwillingsmonomere wurden dabei zunächst templatfrei umgesetzt, um Einflüsse verschiedener Reaktionsparameter auf die Eigenschaften der erhaltenen Kohlenstoffe zu evaluieren. Des Weiteren wurde studiert, wie sich die Zugabe von Hart-Templaten auf das Polymerisationsverhalten der Zwillingsmonomere, sowie die Porosität und Morphologie der daraus resultierenden Kohlenstoffe auswirkt. Für die Charakterisierung der nanostrukturierten Kohlenstoffe wurde vorwiegend auf Elektronenmikroskopie und Stickstoffsorptions-Experimente zurückgegriffen. Mit Hilfe der Zwillingspolymerisation an Hart-Templaten, wie SiO2-Partikeln, Glasfasern und ORMOCER®en konnte die Morphologie, Geometrie, Größe und Porentextur der Kohlenstoffe eingestellt und ein modulares Synthesekonzept für poröse, nanostrukturierte Kohlenstoffe entwickelt werden. Ferner wurden ausgewählte Kohlenstoffe auf Anwendung als Wasserstoffspeicher und Elektrodenmaterial in Lithium-Schwefel-Zellen getestet. In diesem Zusammenhang wurden die Thermogravimetrie, die Differenzkalorimetrie und Stickstoff-Sorptionsmessungen eingesetzt, um die Batterieeigenschaften in Zukunft ohne das Durchführen aufwendiger Zelltests zu prognostizieren.
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Experimental and theoretical studies on germanium-containing precursors for twin polymerizationKitschke, Philipp 10 June 2016 (has links)
Im Fokus dieser Arbeit standen zwei Ziele. Zum einem war es Forschungsgegenstand, dass Konzept der Zwillingspolymerisation auf germaniumhaltige, molekulare Vorstufen wie zum Beispiel Germylene, spirozyklische Germaniumverbindungen und molekulare Germanate zu erweitern und somit organisch-anorganische Komposite beziehungsweise Hybridmaterialien darzustellen. Dazu wurden neuartige Germaniumalkoxide auf der Basis von Benzylalkoholaten, Salicylalkoholaten sowie Benzylthiolaten synthetisiert, charakterisiert und auf ihre Fähigkeit Komposite beziehungsweise Hybridmaterialien über den Prozess der Zwillingspolymerisation zu erhalten studiert.
Ein zweites Ziel dieser Arbeit war es, Beziehungen zwischen der Struktur und der Reaktivität dieser molekularen Vorstufen sowie deren Einfluss auf die Eigenschaften der erhaltenen Polymerisationsprodukte zu identifizieren und systematisch zu untersuchen. Hierfür wurden zum einen verschiedene Substituenten, welche unterschiedliche elektronische sowie sterische Eigenschaften aufweisen, an den aromatischen Einheiten der molekularen Vorstufen eingeführt. Die Effekte der Substituenten auf den Prozess der Zwillingspolymerisation und auf die Eigenschaften der Komposite beziehungsweise Hybridmaterialien wurden für die Verbindungsklasse der Germanium(II)salicylalkoholate, der molekularen Germanate sowie der spiro-zyklischen Siliziumsalicylalkoholate untersucht. Spirozyklische Siliziumsalicylalkoholate, wie zum Beispiel 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin], wurden im Rahmen dieser Arbeit mit einbezogen, da sie aufgrund ihres nahezu idealen Zwillingspolymerisationsprozesses geeignete Modelverbindungen für Reaktivitätsstudien darstellen. Zudem wurde der Einfluss der Substituenten auf die Charakteristika der aus den Kompositen beziehungsweise Hybridmaterialien erhaltenen Folgeprodukte (poröse Kohlenstoffmaterialien und oxydische Materialien) studiert. Des Weiteren wurde eine Serie von spirozyklischen Germaniumthiolaten, welche isostrukturell zu 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin] sind, synthetisiert, um systematisch den Einfluss der Chalkogenide, Sauerstoff und Schwefel, in benzylständiger sowie phenylständiger Position auf deren Reaktionsvermögen im Polymerisationsprozess zu untersuchen.
Die experimentellen Ergebnisse zu den Struktur-Reaktivitätsbeziehungsstudien wurden, soweit es jeweils durchführbar war, mittels quantenchemische Rechnungen validiert und die daraus gezogenen Schlüsse in die Diskussion zur Interpretation der experimentellen Ergebnisse mit einbezogen.:Contents
List of Abbreviations S. 11
1 Introduction S.14
2 Germanium alkoxides and germanium thiolates S. 18
2.1 Preamble S. 18
2.2 Germanium alkoxides S. 18
2.2.1 Germanium(II) alkoxides S. 20
2.2.2 Germanium(IV) alkoxides S. 23
2.2.3 Alkoxidogermanates S. 29
2.3 Germanium thiolates S. 31
2.3.1 Germanium(II) thiolates S. 33
2.3.2 Germanium(IV) thiolates S. 34
2.3.3 Thiolatogermanates and cationic germanium thiolato transition metal complexes S. 36
2.4 Germanium alkoxido thiolates S. 38
2.5 Concluding remarks S. 40
3 Individual Contributions S. 43
4 Microporous Carbon and Mesoporous Silica by Use of Twin Polymerization: An integrated Experimental and Theoretical Approach on Precursor Reactivity S. 46
4.1 Abstract S. 46
4.2 Introduction S.46
4.3 Results and Discussion S. 48
4.3.1 Synthesis and Characterization S. 48
4.3.2 Thermally induced twin polymerization of monosubstituted Precursors (para position) S.49
4.3.2.1 Studies on reactivity according to thermally induced twin polymerization S. 50
4.3.2.2 Characterization of the hybrid materials as obtained by thermally induced twin polymerization S. 51
4.3.2.3 Thermally induced twin polymerization of di-substituted precursors (ortho and para position) S. 52
4.3.2.4 Conclusions drawn for the thermally induced twin polymerization S. 54
4.3.3 Proton-assisted twin polymerization S. 54
4.3.3.1 Studies on the reactivity according to proton-assisted twin polymerization S.55
4.3.3.2 Characterization of the hybrid materials as obtained by proton-assisted twin polymerization S.56
4.3.3.3 Computational studies on proton-assisted twin polymerization S. 58
4.3.3.4 Conclusions drawn for the process of proton-assisted twin polymerization S. 60
4.3.4 Characterization of the porous materials S.61
4.4 Conclusions S.64
4.5 Experimental Section S. 65
4.5.1 General S.65
4.5.2 General procedure for the synthesis of phenolic resin-silica hybrid materials by thermally induced twin polymerization in melt - exemplified for compound 1 S. 66
4.5.3 General procedure for the synthesis of phenolic resin-silica hybrid materials by proton-assisted twin polymerization in solution - exemplified for compound 1 S. 66
4.5.4 General procedure for the synthesis of microporous carbon - exemplified for hybrid material HM-1T S. 66
4.5.5 General procedure for the synthesis of mesoporous silica - exemplified for hybrid material HM-1T S. 67
4.5.6 Single-Crystal X-ray Diffraction Analyses S. 67
4.5.7 Computational Details S. 67
4.6 Acknowledgments S. 68
4.7 Keywords S.68
4.8 Supporting Information Chapter 4 S. 69
5 Synthesis of germanium dioxide nanoparticles in benzyl alcohols – a comparison S. 82
5.1 Abstract S. 82
5.2 Introduction S. 82
5.3 Results and Discussion S.83
5.4 Conclusions S. 87
5.5 Experimental Section S. 87
5.5.1 General S. 87
5.5.2 Syntheses S. 88
5.5.3 Synthesis of GeO2 in ortho-methoxy benzyl alcohol – sample A S. 88
5.5.4 Synthesis of GeO2 in benzyl alcohol under inert conditions – sample B S. 89
5.5.5 Synthesis of GeO2 in benzyl alcohol under ambient conditions – sample C S. 89
5.6 Acknowledgments S. 89
5.7 Keywords S.89
5.8 Supporting Information Chapter 5 S. 90
6 From a Germylene to an “Inorganic Adamantane”: [{Ge₄(μ-O)₂(μ-OH)₄}{W(CO)₅}₄]∙4THF S. 93
6.1 Abstract S.93
6.2 Introduction S. 93
6.3 Results and Discussion S. 94
6.4 Conclusions S. 98
6.5 Experimental Section S. 99
6.5.1 General S.99
6.5.2 Synthesis of germanium(II) (2-methoxyphenyl)methoxide (9) S. 99
6.5.3 Synthesis of [{Ge4(μ-O)2(μ-OH)4}{W(CO)5}4]·4THF (10·4THF) S. 100
6.5.4 Single-Crystal X-ray Diffraction Analyses S. 100
6.5.4.1 Crystal Data for (9)2 S. 101
6.5.4.2 Crystal Data for 10·4THF S. 101
6.5.5 Computational Details S. 101
6.6 Acknowledgments S. 101
6.7 Keywords S.101
6.8 Supporting Information Chapter 6 S. 102
7 Synthesis, characterization and Twin Polymerization of a novel dioxagermine S. 110
7.1 Abstract S. 110
7.2 Introduction S.110
7.3 Results and Discussion S. 111
7.3.1 Single-crystal X-ray diffraction analysis S. 111
7.3.2 IR spectroscopy S. 112
7.3.3 Mass spectrum S. 114
7.3.4 DSC/TGA analysis S. 116
7.3.5 Polymerization S. 117
7.4 Conclusions S. 118
7.5 Materials and Methods S.118
7.5.1 General S. 118
7.5.2 Synthesis of 5-bromo-2-hydroxybenzyl alcohol S. 119
7.5.3 Synthesis of di-tert-butyl-di-ethoxy germane S.119
7.5.4 Synthesis of 6-bromo-2,2-di-tert-butyl-4H-1,3,2-benzo[d]dioxagermine (11) S. 120
7.5.5 Polymerization of compound 11 S. 120
7.5.6 X-ray diffraction analysis of compound 11 S.120
7.5.6.1 Crystal data for compound 11 S.120
7.5.7 Computational Details S.121
7.6 Acknowledgments S.121
7.7 Keywords S. 121
7.8 Supporting Information Chapter 7 S. 122
8 Intramolecular C-O Insertion of a Germanium(II) Salicyl Alcoholate: A Combined Experimental and Theoretical Study S. 125
8.1 Abstract S.125
8.2 Introduction S. 125
8.3 Results and Discussion S.126
8.3.1 Syntheses and Characterization S. 126
8.3.2 1H NMR Spectroscopic Studies S.132
8.3.3 DFT-D Calculations S.134
8.4 Conclusions S. 137
8.5 Experimental Section S. 138
8.5.1 General S. 138
8.5.2 Synthesis of germanium(II) 2-tert-butyl-4-methyl-6-(oxidomethyl)phenolate (12) S. 139
8.5.3 Synthesis of 2,4,6,8-tetrakis(3-tert-butyl-5-methyl-2-oxidophenyl)methanide-1,3,5,7,2,4,6,8-tetraoxidogermocane (13) S. 139
8.5.3.1 Method a) S.139
8.5.3.2 Method b) S. 140
8.5.4 Synthesis of 7,8'-di-tert-butyl-5,6'-dimethyl-3H,4'H-spiro[benzo[d][1,2]oxager-mole-2,2'-benzo[d][1,3,2]dioxagermine] (14) S. 140
8.5.4.1 Method a) S. 140
8.5.4.2 Method b) S. 141
8.5.4.3 Method c) S. 141
8.5.5 Synthesis of the [4-(dimethylamino)pyridine][germanium(II)-2-tert-butyl-4-meth-yl-6-(oxidomethyl)phenolate] (15) S. 141
8.5.6 1H NMR spectroscopic study i) S. 142
8.5.7 1H NMR spectroscopic study ii) S. 142
8.5.7.1 Method a) S. 142
8.5.7.2 Method b) S. 142
8.5.8 1H NMR spectroscopic study iii) S. 142
8.5.8.1 Method a) S. 142
8.5.8.2 Method b) S. 142
8.5.9 1H NMR spectroscopic study iv) S. 143
8.5.10 1H NMR spectroscopic study of the mixture of complex 15 and 3-tert-butyl-2-hydroxy-5-methylbenzyl alcohol in CDCl3 S. 143
8.5.11 1H NMR spectroscopic study of complex 15 in CDCl3 at elevated temperature S. 143
8.5.12 Reaction of complex 15 at elevated temperature S. 143
8.5.13 Single-crystal X-ray diffraction analyses S. 143
8.5.14 Computational Details S.144
8.6 Acknowledgments S. 145
8.7 Keywords S.145
8.8 Supporting Information Chapter 8 S. 146
9 Porous Ge@C materials via twin polymerization of germanium(II) salicyl alcoholates for Li-ion batteries S. 159
9.1 Abstract S. 159
9.2 Introduction S. 159
9.3 Results and Discussion S. 160
9.3.1 Synthesis and Characterization of germylenes S. 160
9.3.2 Twin polymerization S. 164
9.3.2.1 Studies on the reactivity S. 164
9.3.2.2 Characterization of the hybrid materials obtained by thermally induced twin polymerization S. 166
9.3.3 Synthesis and characterization of porous materials S. 168
9.3.4 Electrochemical measurements S. 170
9.4 Conclusions S. 172
9.5 Experimental Section S.172
9.5.1 General S.172
9.5.2 Synthesis of germanium(II) 2-(oxidomethyl)phenolate (16) S. 174
9.5.3 Synthesis of germanium(II) 4-methyl-2-(oxidomethyl)phenolate (17) S. 174
9.5.4 Synthesis of germanium(II) 4-bromo-2-(oxidomethyl)phenolate (18) S. 175
9.5.5 General procedure for the synthesis of phenolic resin-germanium oxide hybrid materials by thermally induced twin polymerization in melt - exemplified for compound 16 S. 175
9.5.6 General procedure for the synthesis of porous Ge@C materials - exemplified for hybrid material HM-16 S.175
9.5.7 General procedure for the synthesis of germanium oxide - exemplified for hybrid material HM-16 S.176
9.5.8 Single-crystal X-ray diffraction analyses S. 176
9.5.9 Computational Details S. 177
9.5.10 Electrode fabrication, cell assembly and electrochemical measurements S. 178
9.6 Acknowledgments S.178
9.7 Keywords S. 178
9.8 Supporting Information Chapter 9 S.179
10 From molecular germanates to microporous Ge@C via twin polymerization S.199
10.1 Abstract S.199
10.2 Introduction 199
10.3 Results and Discussion S. 201
10.3.1 Syntheses and Characterization S. 201
10.3.2 Twin polymerization of germanate 19 S. 204
10.3.3 Synthesis and characterization of the porous materials S. 205
10.3.4 Electrochemical measurements S.206
10.4 Conclusions S. 207
10.5 Experimental Section S. 208
10.5.1 General S. 208
10.5.2 Synthesis of bis(dimethylammonium) tris[2-(oxidomethyl)phenolate(2-)]germa-nate (19) S. 209
10.5.3 Synthesis of bis(dimethylammonium) tris[4-methyl-2-(oxidomethyl)pheno-late(2-)]germanate (20) S. 210
10.5.4 Synthesis of bis(dimethylammonium) tris[4-bromo-2-(oxidomethyl)pheno-late(2-)]germanate (21) S.210
10.5.5 Synthesis of dimethylammonium bis[2-tert-butyl-4-methyl-6-(oxidomethyl)phe-nolate(2-)][2-tert-butyl-4-methyl-6-(hydroxymethyl)phenolate(1-)]germanate (22) S. 211
10.5.6 Synthesis of phenolic resin-germanium dioxide hybrid materials by thermally induced twin polymerization in melt - HM-19 S. 211
10.5.7 Synthesis of porous Ge@C material C-19 starting from HM-19 S. 212
10.5.8 Synthesis of germanium dioxide material Ox-19 - starting from HM-19 S.212
10.5.9 Single-crystal X-ray diffraction analyses S. 212
10.5.10 Electrode fabrication, cell assembly and electrochemical measurements S.213
10.6 Acknowledgments S. 214
10.7 Keywords S. 214
10.8 Supporting Information Chapter 10 S.215
11 Chiral Spirocyclic Germanium Thiolates – An Evaluation of Their Suitability for Twin Polymerization based on A Combined Experimental and Theoretical Study S.226
11.1 Abstract S.226
11.2 Introduction S. 226
11.3 Results and Discussion S.227
11.3.1 Syntheses and Characterization S. 227
11.3.2 Studies on twin polymerization S.229
11.3.3 Computational studies on proton-assisted twin polymerization S. 232
11.4 Conclusions S. 235
11.5 Acknowledgments S. 236
11.6 Keywords S.236
11.7 Supporting Information Chapter 11 S.237
12 Concluding remarks S. 257
12.1 Discussion S.257
12.1.1 Twin polymerization of germanium-containing precursors S. 257
12.1.2 Reactivity studies of precursors towards their twin polymerization S.260
12.2 Summary and Outlook S. 264
Selbständigkeitserklärung S.266
Curriculum Vitae S.267
Publications S. 268
List of Publications in Peer-Reviewed Journals S. 268
List of Conference Contributions S.269
Research proposals, additional conference and summer school participations S. 270
Acknowledgments S. 271
References S. 272
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