Polyaniline Oligomers Research Articles

Evidence for Superoxide-Initiated Oxidation of Aniline in Water by Pulsed, Atmospheric Pressure Plasma.

Plasma-driven solution electrochemistry (PDSE) uses plasma-generated reactive species to drive redox reactions in solution. Nonthermal, atmospheric pressure plasmas, when irradiating water, produce many redox species. While PDSE is a promising chemical tool, there is limited insight into the mechanisms of the reactions due to the variety of short-lived reagents produced. In this study, we use aniline as a model system for studying redox mechanisms of PDSE. We show that the plasma irradiation of aqueous aniline solutions drives the formation of polyaniline oligomer, which is suppressed under acidic starting conditions. The addition of (2,2,6,6-Tetramethylpiperidin-1-yl)oxyl (TEMPO), a radical scavenger, decreases the formation of oligomer by 80%, and the addition of superoxide dismutase fully hinders oligomerization. These results lead us to conclude that the oligomerization of aniline by plasma irradiation is initiated by superoxide. This discovery provides novel insights into PDSE mechanisms and illustrates a potential method of harnessing superoxide for chemical reactions.

Comparative study of cyclic polyaniline oligomers with linear and bent structures

In the present work, Grimme’s D3 dispersion corrected density functional theory (DFT-D3) is used for the comparative study of cyclic polyaniline oligomers with linear and bent structures, for the first time. Molecular design and spectral characterisation of these compounds are performed at the B3LYP-D3/6-311G(d,p) and the B3LYP-D3/6-311++G(d,p) levels of theory. The formation mechanism of cyclic polyaniline oligomers compared to the linear and bent structures is discussed. Molecular orbital (MO) calculations are applied to study the electronic structure, and estimate the energy gap between the highest occupied (HOMO) and the lowest unoccupied (LUMO) molecular orbitals. The density of states (DOS) diagrams are used to evaluate the nature of valence and conduction bands and investigate the electrical conductivity. The calculated infrared (IR), ultraviolet-visible (UV-Vis) and nitrogen-15 nuclear magnetic resonance (15N NMR) spectra of these compounds are compared to the theoretical and experimental spectra of polyaniline. Results show that cyclic polyanilines are nonpolar in comparison to the linear and bent structures. The band gap of these molecules is larger than the linear and bent ones. The band gap of cyclic oligomers increases with the increasing size of the rings. These results provide useful information for the characterisation of these novel compounds.

Covalent Immobilization of Polyaniline Doped with Ag+ or Cu2+ on Carbon Nanotubes for Ethylene Chemical Sensing.

Multi-walled carbon nanotubes (MWCNTs) are promising materials for chemical gas sensing because of their high electrical and mechanical properties and significant sensitivity to changes in the local environment. However, high-content MWCNT films suffer from the low tunability of the electrical resistance, which is crucial for high chemoresistive sensing performance. This study reports the conjugation of MWCNTs and oligomers of polyaniline (PANI) doped with Ag+ or Cu2+ incorporated into a PVC/polyacrylate. MWCNTs were sonicated in n-methyl pyrrolidine (NMP), and PANI was conjugated via a 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and an N-hydroxysuccinimide (EDC/NHS) process. MWCNT/PANI Ag+ or Cu2+ conjugates were doped to form a coordinate bond. The doped conjugates were successfully incorporated into the PVC/polyacrylate. These MWCNT/PANI conjugates doped were exposed to different concentrations of ethylene gas to examine their feasibility for ethylene detection.

Rechargeable Zn-Air Batteries with Outstanding Cycling Stability Enabled by Ultrafine FeNi Nanoparticles-Encapsulated N-Doped Carbon Nanosheets as a Bifunctional Electrocatalyst.

Despite grand advances in Zn-air batteries in recently years, their commercialization remains challenging due largely to the lack of efficient bifunctional oxygen catalysts. Herein, we report the crafting of a bifunctional electrocatalyst comprising ultrafine alloyed FeNi nanoparticles encapsulated within N-doped layered carbon nanosheets (denoted FeNi/N-LCN) for high-efficiency Zn-air batteries. The FeNi/N-LCN electrocatalyst is yielded via the coordination of triphenylimidazole-containing polyaniline (TPANI) oligomer with Fe- and Ni-containing precursors, followed by hydrogen binding with melamine and subsequent pyrolysis. The as-constructed FeNi/N-LCN manifests outstanding activity and stability toward both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The primary Zn-air battery assembled with FeNi/N-LCN delivers both high specific capacity and peak power density. Remarkably, the rechargeable Zn-air battery can be repeatedly charged and discharged for 1100 h at 5 mA cm-2 and for 600 h at 10 mA cm-2, representing the highest cycling stability among various reported Zn-air batteries.

IL-assisted synthesis of defect-rich polyaniline/NH2-MIL-125 nanohybrids with strengthened interfacial contact for ultra-fast photocatalytic degradation of acetaldehyde under high humidity

A novel strategy and design for ionic liquid (IL) assisted in-situ grafting of polyaniline (PANI) oligomers in NH2-MIL-125 was proposed to synthesize the defect-rich IL-PANI/NMIL(Ti) nanohybrids with an intimate interface for the superior photodegradation of CH3CHO. PANI was dissolved into small oligomers with the aid of IL [EMIM]BF4 and was composited to NH2-MIL-125 by a strong interfacial connection through Ti-N bonds (XPS) with high dispersion and large surface area (BET = 1125 m2/g). Characterizations results showed that smart grafting of PANI-oligomers generated abundant defects (3.4-times, ESR) and intensified Lewis acid sites (1.2-times, CO-DRIFT) in IL-PANI/NMIL(Ti) compared to NH2-MIL-125. It promoted adsorptive interactions for aldehyde VOCs capturing, which in-turn increased the adsorption rate (ka) of CH3CHO. Smart grafting also improved the light absorption of IL-PANI/NMIL(Ti) from 500 to 800 nm, reduced band gap (1.7 eV), increased photo-current density (2.2-folds of pure MOF), enhanced O2− and OH radicals generation and improved e−/h+ mobility. As a result, IL-PANI/NMIL(Ti) showed 11.4 and 4.2 times higher ka (0.262 min−1) of CH3CHO photodegradation kinetics than PANI and NH2-MIL-125, respectively, at 75% relative humidity (RH). The ka of CH3CHO degradation was steadily increased with increasing humidity (<80 RH%), indicating that H2O from humid air was beneficial for CH3CHO degradation. Furthermore, IL-PANI/NMIL(Ti) exhibited the excellent recycling stability compared to NH2-MIL-125, as only a 5% decrease in photocatalytic activity was observed after five cycling runs. Considering the excellent photostability and ultrafast photodegradation of CH3CHO, the current study opens up new perspectives in fabricating MOFs for a wide-range of practical applications.

Deposition Behavior of Polyaniline on Carbon Nanofibers by Oxidative Chemical Vapor Deposition.

Oxidative chemical vapor deposition (oCVD) offers unique advantages as a liquid-free processing technique in synthesizing and integrating conducting polymers, including polyaniline (PANI), by enabling conformal coatings onto nanostructured substrates, like carbon nanofibers. With relatively thick nanofiber mats, the challenge is to ensure uniform coating thickness through the porous substrates. Here, the substrate temperature during oCVD is found to be a primary factor influencing PANI coating uniformity. Coating uniformity is enhanced by operating at a higher substrate temperature, where monomer adsorption is believed to be limiting relative to intrinsic reaction kinetics. Also, a higher substrate temperature leads to significantly less PANI oligomers and more PANI in the emeraldine oxidation state. A systematic study of oCVD kinetics with substrate temperature shows a reaction-limited regime at lower substrate temperatures with an activation energy of 12.0 kJ/mol, which is believed to be controlled by the self-catalyzed PANI polymerization reaction that transitions at higher substrate temperatures above 90 °C to an adsorption-limited regime as indicated by a negative activation energy of -18.8 kJ/mol. Overall, by operating within an adsorption-limited oCVD regime, more uniform oCVD PANI coatings on electrospun carbon nanofiber mats have been achieved.

Calculations of oxygen and humidity influence on properties of pernigraniline base polyaniline oligomers

In spite of extensive investigation and applications, influence of oxygen (O), and humidity on polyaniline (PANI) behaviour is not well understood. For this reason we have performed semi-empirical quantum mechanics, and ab-initio calculations of the pernigraniline base (PNB) PANI oligomers, of various lengths, before and after approach of H2O, O2, and hydroxyl (OH−) group, and attachment of OH− and O to various molecular positions. Structure, charge and electrostatic potential distribution, relevant energies and enthalpies, infrared and electronic spectra of the PNB tetramer equilibrium conformation, and their changes induced by specific OH−, and O attachments are determined. These results provide identification of the most probable positions for O2 and H2O approach to PNB_PANI, enthalpies of OH− and O attachments to them, changes of molecular properties induced by the attachments, and infrared and electronic modes that are most suitable for the attachments detection. The results are compared to the existing experimental data, and the results of similar calculations, and implications for the PNB_PANI applications are notified.

Construction of a DNA Origami Based Molecular Electro-optical Modulator.

An electro-optical modulator was constructed using a DNA nanostructure scaffold with oligomers of poly(phenylenevinylene) and polyaniline. A molecular device containing one each of the functional molecules was assembled in a DNA origami. The constructs formed an "X" shape and were visualized by atomic force microscopy. In response to redox reconfiguration, the device reversibly altered fluorescence signal output. This molecular self-assembly strategy provides opportunities to make unique material composites that are difficult to achieve by blending. The strategy offers a "plug and play" format that may lead to many new functions.

Tetraaza[14]- and Octaaza[18]paracyclophane: Synthesis and Characterization of Their Neutral and Cationic States.

Two kinds of aza[1n]paracyclophanes, tetraaza[14]paracyclophane (P4) and octaaza[18]paracyclophane (P8), were synthesized as the smallest and the largest monodisperse macrocyclic oligomers of polyaniline ever made. Herein we report the electronic nature of the cationic species of these two macrocycles with different ring size. By combining ESR spectroscopy and DFT calculations it was suggested that P4·+ was classified as delocalized class III or poised on the class II/III borderline while P8·+ was regarded as a localized class II mixed-valence system. We successfully isolated the dication of P4 as a stable dicationic salt P42+·2[SbF6]-, and the structure of P42+ was determined by X-ray crystal analysis. Variable-temperature NMR measurements for P42+·2[SbF6]- unequivocally showed that P42+ was a 22π electron system with a singlet ground state. The supercharged hexacation of P8 was also isolated as P86+·6[SbCl6]-, and X-ray crystal analysis revealed that P86+ includes one SbCl6- anion in its macrocyclic cavity.

Voltage and capacity control of polyaniline based organic cathodes: An ab initio study

Abstract Polyaniline (PANI) is a promising organic cathode material for electrochemical batteries. Its specific capacity is limited by irreversible formation of pernigraniline base, and its energy density is limited by the voltage which could be improved. We present an ab initio study of PANI and PANI functionalized with functional groups which lead to increased voltage and stabilization of the pernigraniline salt. Specifically, the oxidation potential achieved by functionalization with CN on the nitrogen is computed to be 1.3 V higher than that of pristine PANI oligomer, leading to a higher voltage, and the formation of the pernigraniline base is predicted to be simultaneously suppressed, leading to a higher reversible capacity. Therefore, functionalized PANI could be a promising candidate organic cathode for Li-ion batteries.

Controlled self-assembly of oligomers-grafted fibrous polyaniline/single zirconium phosphate nanosheet hybrids with potential-responsive ion exchange properties

A novel α-zirconium phosphate (α-ZrP) nanosheet-implanted fibrous polyaniline (PANI) hybrid film with potential-responsive ion exchange function is fabricated by a facile pulse electrochemical synthesis technique. The suppression effect of electrical double layer at the conducting substrate/colloidal solution interface for the formation of PANI/α-ZrP hybrid film is effectively improved through a layer of pre-deposited PANI oligomers, whose thickness plays an important role in the self-assembly of the hybrid film. During the pulse electrochemical synthesis process, the oligomers-grafted fibrous PANI is electropolymerized in the period of high potential; and the translucent exfoliated α-ZrP nanosheets are uniformly implanted into the fibrous PANI by electrostatic self-assembly in the following period of low potential. The amount ratio of α-ZrP nanosheet and fibrous PANI can be regulated by adjusting the pulse width based on their growth rate. The results show that the optimized pulse width for the fabrication of PANI/α-ZrP hybrid film with three-dimensional porous structure is 0.8s. Under this condition, the generated PANI/α-ZrP hybrid film shows fast uptake/release ability and high capacity for the separation of Pb2+ ions from aqueous solution based on its unique potential-induced ion exchange process. The adsorption equilibrium time is less than 30s, and the ion exchange capacity of porous PANI/α-ZrP hybrid film reaches 123.5mgg−1, which is almost 9 times higher than that of the compact PANI/α-ZrP hybrid film. Furthermore, the ion exchange capacity retains 85.2% of its initial value after 1000 cycles.

Electrodeposition of self-doped copolymers of aniline with aminobenzensulfonic acids on stainless steel. Morphological and electrochemical characterization

Self-doped conducting polyaniline (PAn) films were deposited on passive stainless steel (SS) AISI304 substrates by cyclic potential sweep deposition from aqueous mixed monomer solutions of aniline (An) and different aminobenzenesulfonic acids (2-, 3- or, 4-aminobenzenesulfonic acid, ABSA), without the presence of a supporting electrolyte. Two different An concentrations were examined (0.01 and 0.05 M), while the concentration of each ABSA used was kept constant at 0.1 M. The surface morphology and roughness of the produced stable conducting copolymer thin films was studied by atomic force microscopy (AFM) and their electrochemical behavior by cyclic voltammetry. The decrease of An concentration enhanced the electropolymerization in the case of 2- and 3-ABSA, namely, orthanilic (OA) and metanilic (MA) acids, respectively, while a deceleration was observed for 4-ABSA (sulfanilic acid, SA). The shapes and sizes of the obtained morphological features depended on the ABSA reactivity and An concentration. AFM data indicated the formation of globular micro/nanostructures for all the examined copolymers, P(An-co-ABSA). Tubular micro/nanostructures, which were more desirable due to their promising practical applications, were apparent only in case of OA and SA and in larger numbers at the lower An concentration of 0.01 M. As ABSA had the function of the comonomer, surfactant, and internal dopant, it is suggested that the tubular micro/nanostructures were rather related to an interfacial self-assembly of sulfonated PAn oligomers at the early stage of the copolymerization process. Cyclic voltammetry indicated that redox processes of the SS|P(An-co-ABSA) electrodes in acid solutions are characteristic of a partially sulfonated PAn. The electrochemical activity of the SS|P(An-co-ABSA) electrodes is also kept in neutral media. Open circuit potential measurements and electrochemical impedance spectroscopy show that the SS|P(An-co-ABSA) electrodes are stable in acid media. Electronic and steric effects control the fraction of ABSA and its distribution in the copolymer chain resulting in differences in the redox potential and charge storage in the three copolymers.

Microfibers from interpolymer complexation of κ-carrageenan and oligomers of polyaniline for glucose detection

The molecular order and orientation significantly influence the physical properties of conjugated polymers and the corresponding performance in electronic devices. The precise synthesis and characterization are the challenges to obtain high quality polymer crystalline micro/nanostructures, on the basis of which, the charge transport mechanisms can be discussed and the device performance can be improved. A micro-fibrous complex of conductive polymer and natural polysaccharide has been formed during the in situ polymerization of aniline in the aqueous solution of κ-carrageenan. With the template of the polyanion, aniline is polymerized and polyaniline (PANI) chain grows in the vicinity of sulfonic acid groups. Through the comprehensive characterizations of UV–vis spectra, wide-angle X-ray diffraction, and thermal gravimetric analysis, the assembly structure of the interpolymer complex has been illuminated, i.e., oligomers of PANI with expanded conformation are formed, the electrostatic interaction between the protonated PANI oligomers and anionic κ-carrageenan makes the chains of PANI and κ-carrageenan bound together, and a micro-fibrous complex is formed with enhanced orientation of both PANI and κ-carrageenan, leading to an enhanced conductivity of the complex. The glucose biosensor made of the complex shows high detecting sensitivity and broad linear range in the recognition of the glucose due to its high conductivity and good compatibility with the enzyme.

Enhanced electrical conductivity of polyurethane-polyaniline composites containing core–shell particles through conductive-shell effect

In this study SiO2 nanoparticles coated with polyaniline (PANI) shell of various thicknesses have been fabricated successfully by in situ polymerization of aniline on the silica surface through the chemical bonding between amino groups of silica surface and aniline. The addition procedure of dodecylbenzenesulfonic acid plays a key role on whether the thick-shell nanoparticles can be prepared successfully or not. The SiO2-PANI core–shell nanoparticles and PANI oligomers were reacted with isocyanates to prepare the conductive polyurethane-PANI-silica hybrid films. Under the same PANI content in nanocomposites, the hybrid films containing the nanoparticles with the thicker PANI shell show superior enhancement on electrical conductivities compared to those containing the thinner-PANI-shell nanoparticles. On the 5-wt.% PANI content, the surface resistance of the nanocomposites can reduce to ∼106Ω/sq, lowering two orders, while the nanoparticles with 1.35-wt.% PANI shell are replaced by those with 13.8-wt.% PANI shell in use. According to the general effective media analysis, the percolation threshold (0.0277) is much lower than the critical volume fraction (0.16) for random packing in three dimensions. As a result of the low percolation threshold, we infer that the conducting core–shell nanoparticles form electrical channels due to the surface connection effect, resulting in the momentous enhancements in the electrical conductivity.

Self-assembly of nanostructures obtained in a microwave-assisted oxidative polymerization of aniline

For the first time, microwave assisted aniline oxidative polymerization is performed in the presence of acetic acid (CH3COOH) and ammonium hydroxide (NH4OH) at different microwave power levels. The reaction system is kept at constant temperature of 24±1°C. The products are investigated by Fourier Transform Infrared Spectroscopy (FTIR), Raman, solid-state Nuclear Magnetic Resonance (NMR) and Electron Paramagnetic Resonance (EPR) spectroscopies. EPR signals in polyaniline (PANI) originate from the polarons formed upon protonation and doping by acid. The microwave radiation causes an increase in the spin concentration which is slightly more evident for 8 W than for 93 W. The morphol- ogy is investigated by using scanning electron microscopy (SEM). SEM micrographs revealed the formation of nanorods (in the presence of CH3COOH) and nanospheres (in the presence of NH4OH). FTIR, Raman and solid-state NMR spectro- scopies indicate the presence of PANI and aniline oligomers. X-ray Diffraction (XRD) measurements showed the presence of well-ordered structures.

Montmorillonite intercalated by conducting polyanilines

Structure and conductivity of nanocomposite conducting polymer/montmorillonite have been investigated for samples prepared by the polymerization of aniline hydrochloride with ammonium peroxodisulfate in aqueous suspension of montmorillonite. Samples were characterized by combination of X-ray powder diffraction (XRPD), IR spectroscopy and electrical conductivity measurements. Structure analysis based on combination of molecular modeling and experiment (XRPD and IR spectroscopy) revealed the structure of nanocomposite, including the interlayer structure of montmorillonite, and helped to understand the processes during nanocomposite preparation. Partial intercalation of polyaniline oligomers into the interlayer space of montmorillonite led to the large inhomogeneity of interlayer structure, which results in dramatic decrease of the electrical conductivity of nanocomposite in comparison with pure polyaniline.

Polyaniline: The infrared spectroscopy of conducting polymer nanotubes (IUPAC Technical Report)

Polyaniline (PANI), a conducting polymer, was prepared by the oxidation of aniline with ammonium peroxydisulfate in various aqueous media. When the polymerization was carried out in the solution of strong (sulfuric) acid, a granular morphology of PANI was obtained. In the solutions of weak (acetic or succinic) acids or in water, PANI nanotubes were produced. The oxidation of aniline under alkaline conditions yielded aniline oligomers. Fourier transform infrared (FTIR) spectra of the oxidation products differ. A group of participants from 11 institutions in different countries recorded the FTIR spectra of PANI bases prepared from the samples obtained in the solutions of strong and weak acids and in alkaline medium within the framework of an IUPAC project. The aim of the project was to identify the differences in molecular structure of PANI and aniline oligomers and to relate them to supramolecular morphology, viz. the nanotube formation. The assignment of FTIR bands of aniline oxidation products is reported.

PSf/PANI nanocomposite membrane prepared by in situ blending of PSf and PANI/NMP

A simplified method to prepare polysulfone (PSf)/polyaniline (PANI) nanocomposite membrane was proposed. With this method, aniline was polymerized using ammonium peroxydisulfate as oxidant and N-methyl-2-pyrrolidone (NMP) as solvent, which was also the solvent of PSf. The mixture after aniline polymerization containing PANI nanospheres, PANI oligomers, NMP and inorganic ions, named PANI/NMP, was added directly into the solution consisting of PSf and NMP without any post-processing to form membrane casting solution. Then, PSf/PANI nanocomposite membranes were prepared via immersion phase inversion process using the casing solution. This method is called in situ blending method. PANI oligomers were soluble in both water and organic solvent while PANI nanospheres were dispersed in both water and organic solvent. The behaviors of PANI oligomers and PANI nanospheres during membrane formation were investigated and analyzed. A large portion of PANI oligomers and a small portion of PANI nanospheres would be leached out of the casting film during the phase separation and act as pore formers, inducing the enhancement of membrane porosity and surface pore size. A large portion of PANI nanospheres and a small portion of PANI oligomers residing in the prepared membranes favored the enhancement of membrane hydrophilicity, breaking strength and thermal stability. Compared with PSf membrane, PSf/PANI nanocomposite membranes obtained with this method had more hydrophilic surface, higher porosity, larger surface pore size, less acicular pores, thicker skinlayer, wider pores beneath the skinlayer, better vertically interconnected finger-like pores and less macrovoids. Pure water fluxes of PSf/PANI nanocomposite membranes were 1.7–4.1 times that of PSf membrane and BSA rejections of the membranes were all above 96%. During BSA ultrafiltration, PSf/PANI nanocomposite membranes showed slower flux decline rate and higher flux recovery ratio values after simple water flushing than PSf membrane.

Synthesis and properties of conducting organic/inorganic polyurethane hybrids

A series of polyurethane/polyaniline/silica organic/inorganic hybrids were synthesized via the conventional polyurethane (PU) prepolymer technique. Amine-endcapped polyaniline (PANI) with low molecular weight and higher solubility was firstly synthesized. This PANI oligomer was then used together with nano-silica bearing silanol groups as chain extenders to prepare the conducting polyurethane hybrids. The polyurethane hybrids were designated as PU- xPANI- ySiO 2 ( x + y = 1). For comparison, the urethane-aniline block copolymer and the PU/silica hybrid were designated as PU-PANI and PU-SiO 2, respectively. The structures of PU-PANI, PU-SiO 2 and conducting polyurethane hybrids were confirmed by FT-IR, solid-state 13C, and 29Si NMR spectra. In nano-silica containing organic/inorganic conducting polyurethane hybrids, UV–vis spectra revealed the maximum absorption bands similar to that of PU-PANI. X-ray diffraction patterns indicated that these samples are typical of semicrystalline/amorphous materials. SEM image of PU-0.5PANI-0.5SiO 2 showed that PANI was dispersed homogeneously and interconnected continuously in the insulating PU-silica matrix. TGA results of the polymer hybrids exhibited higher thermal stabilities and lower decomposition rates than that of PU-PANI both in nitrogen and air. Differential scanning calorimetry (DSC) studies indicated that the polyurethane hybrids had higher glass-transition temperatures (T g) with the increase of PANI, but lower than that of PU-PANI. Stress–strain curves for all of the polyurethane hybrids showed the elastomeric behavior of typical polyurethanes. The surface resistivity values of all hybrids were about 10 8 ∼ 10 10 Ω/sq. and might meet the requirement of the anti-electrostatic materials.

Investigation of Corrosion-Inhibiting Aniline Oligomer Thin Films on Iron Using Photoelectron Spectroscopy

Polyaniline (PANI) is capable of inhibiting corrosion on iron by inducing the formation of a passive oxide film. The underlying mechanism however, is unknown. We have used photoelectron emission spectromicroscopy of thin films of a model PANI oligomer to investigate its interaction with the iron oxide film covering the iron surface. The oligomer chosen was a phenyl-capped aniline tetramer (PCAT). Thin undoped films of PCAT in its leucoemeraldine form were prepared by physical vapor deposition to obtain films from ∼1 A to over 10 nm thick. Films were investigated with a photoelectron emission microscope (PEEM) using synchrotron radiation to obtain spatially resolved valence band photoemission spectra. Analysis of PEEM results suggest that PCAT is capable of migrating several micrometers along the substrate surface and causes a decrease in substrate work function wherever present. High-resolution core level and valence band photoelectron spectroscopy using a laboratory-based photon source was used to charac...