Repository of University of Nova Gorica

Search the repository
A+ | A- | Help | SLO | ENG

Query: search in
search in
search in
search in
* old and bologna study programme


1 - 9 / 9
First pagePrevious page1Next pageLast page
Air-water interface-assisted synthesis and charge transport characterization of quasi-2d polyacetylene films with enhanced electron mobility via ring-opening polymerization of pyrrole
Kejun Liu, Nadiia Pastukhova, Egon Pavlica, Gvido Bratina, Xinliang Feng, 2024, other component parts

Abstract: Water surfaces catalyze some organic reactions more effectively, making them unique for 2D organic material synthesis. This report introduces a new synthesis method via surfactant-monolayer-assisted interfacial synthesis on water surfaces for ring-opening polymerization of pyrrole, producing distinct polypyrrole derivatives with polyacetylene backbones and ionic substitutions. The synthesis result in quasi 2D polyacetylene (q2DPA) film with enhanced charge transport behavior. We employed time-of-flight photoconductivity (TOFP) measurements using pulsed laser light of tunable wavelength for photoexcitation of the charge carriers within the q2DPA film. The charge transport was measured in the lateral direction as a function of external bias voltage ranging from 0 V to 200 V. We observed high electron mobility ({\mu}) of q2DPA reaching values of 375 cm2 V-1 s-1 at bias voltage Vb = -20V and photon energy of 3.8 eV.
Keywords: air-water interface-assisted synthesis, time-of-flight photoconductivity, 2D polymers, quasi 2D polyacetylene, q2DPA
Published in RUNG: 09.04.2024; Views: 717; Downloads: 2
.pdf Full text (3,89 MB)
This document has many files! More...

Designing atomic interface in ▫$Sb_2S_3/CdS$▫ heterojunction for efficient solar water splitting
Minji Yang, Zeyu Fan, Jinyan Du, Chao Feng, Ronghua Li, Beibei Zhang, Nadiia Pastukhova, Matjaž Valant, Matjaž Finšgar, Andraž Mavrič, Yanbo Li, 2024, original scientific article

Abstract: In the emerging Sb2S3‐based solar energy conversion devices, a CdS buffer layer prepared by chemical bath deposition is commonly used to improve the separation of photogenerated electron‐hole pairs. However, the cation diffusion at the Sb2S3/CdS interface induces detrimental defects but is often overlooked. Designing a stable interface in the Sb2S3/CdS heterojunction is essential to achieve high solar energy conversion efficiency. As a proof of concept, this study reports that the modification of the Sb2S3/CdS heterojunction with an ultrathin Al2O3 interlayer effectively suppresses the interfacial defects by preventing the diffusion of Cd2+ cations into the Sb2S3 layer. As a result, a water‐splitting photocathode based on Ag:Sb2S3/Al2O3/CdS heterojunction achieves a significantly improved half‐cell solar‐to‐hydrogen efficiency of 2.78% in a neutral electrolyte, as compared to 1.66% for the control Ag:Sb2S3/CdS device. This work demonstrates the importance of designing atomic interfaces and may provide a guideline for the fabrication of high‐performance stibnite‐type semiconductor‐based solar energy conversion devices.
Keywords: alumina, defect passivation, interface engineering, photoelectrochemical water splitting
Published in RUNG: 11.03.2024; Views: 740; Downloads: 2
.pdf Full text (4,59 MB)
This document has many files! More...

On Karttunen’s "The syntax and semantics of questions"
Elena Guerzoni, 2022, independent scientific component part or a chapter in a monograph

Abstract: Karttunen’s article on the syntax and semantics of questions is a milestone in the truth-conditional compositional semantics of interrogatives and of verbs that embed them. It is the first comprehensive study of the mapping between the syntax and the interpretation of the three different types of questions (polar, constituent and alternative questions) and presents the first semantic analysis of question-embedding verbs (QEVs henceforth) that assumes the same intensions for matrix and embedded interrogatives. This analysis continues to vastly inspire the ongoing research on the properties of questions and QEVs. This chapter illustrates Karttunen’s theory focusing on those formal details that have been the most influential in subsequent literature. In doing so, however, I will take the liberty to suggest a less than literal rendition of these details, in an attempt to make the discussion more accessible to today’s reader. The main departure that I make here from Karttunen’s 1977 is in the formal framework. Whereas Karttunen adopts Montague’s PTQ, here I will expose his ideas in Heim and Kratzer‘s type driven semantics.
Keywords: interrogatives, questions, syntax-semantics interface, compositionality, wh-movement
Published in RUNG: 20.02.2024; Views: 685; Downloads: 4
URL Link to file
This document has many files! More...

Chemical (in)stability of an interface between metals and Bi[sub]2Se[sub]3 topological insulator
Katja Ferfolja, Mattia Fanetti, Sandra Gardonio, Matjaž Valant, 2019, published scientific conference contribution abstract

Abstract: Our research is dedicated to a study of an interface between a Bi2Se3 topological insulator (TI) and various metals due to the essential need for providing a metal contact for devices. The main objective is to characterize structural and chemical properties at the interface, where the electronic properties of the TI can be affected. The structure of the interface and processes happening at it are investigated by microscopy (SEM, TEM, STM) and spectroscopy techniques (EDX, XPS). The research started with the noble metals: Ag, Au and Pt. A good stability was observed for Au and Pt, whereas Ag reacted with Bi2Se3 already at room temperature, producing Ag2Se and AgBiSe2 phase. Interface stability was also checked at high temperature and results showed that the Au coating undergoes a coalescence process starting from 100 °C whereas the interface with Pt does not show any change at least up to 350 °C. At present we are focused on the interface with Ti, a metal which is regularly used as an adhesive layer in electrical contacts. At low coverage (<30 nm) Ti forms an extremely flat film, smoother than Au, Ag or Pt. At higher coverage the film undergoes buckle delamination, likely induced by stress release. The observed morphology indicates that a chemical interaction leads to the growth of the initial smooth Ti epitaxial film. Se interdiffusion and formation of interfacial TixSey phase is envisaged, as suggested from preliminary TEM observations of the interface structure. The presented results show the importance of the processes happening at the interface, especially solid-state chemical reactions, which are often neglected in the study of systems with metal/TI interfaces. Such instability has to be taken into account since the produced phases can affect transport properties of the material, increase a contact resistance or affect functionality of devices.
Keywords: Bi2Se3, interface, topological insulator, chemical instability
Published in RUNG: 20.08.2021; Views: 2193; Downloads: 12
URL Link to full text
This document has many files! More...

Room-temperature solid-state reaction at the Ag/Bi[sub]2Se[sub]3 interface
Katja Ferfolja, Mattia Fanetti, Iuliia Mikulska, Sandra Gardonio, Matjaž Valant, 2017, published scientific conference contribution abstract

Abstract: Topological insulators (TI) are materials that, while having a forbidden bandgap in bulk, are conductors at their surface due to presence of surface-localized electronic states crossing the band gap. [1] TIs are possible because of a time reversal symmetry and spin-orbit coupling, which invert bulk band states in their energy positions and make the bulk band structure non trivial. Consequently, the topological surface states (TSS) emerge on the surface of these materials. Unlike ordinary surface states, TSS cannot be destroyed by contamination or defects on the surface. Additionally, TSS are also spin polarized, which means that when applying current to TI, the current will have a well defined direction of the electron spins. The topological insulators - a relatively new class of materials - are being widely studied not only from fundamental aspects, but also from their applicative perspectives. It has been predicted that TIs could be used in fields of spintronics, electronics and catalysis. [2,3] Interestingly, only a few studies about metal/TI interfaces have been reported. This is surprising since integration of TI in the applications will often necessitate an interface with the metal, therefore, detailed knowledge on chemistry and electrical conditions at the interface will be required. In this contribution results on research on the chemistry of the Ag/Bi2Se interface will be presented, in particularonthesolid-statereactionbetweennanoparticles.IthasbeenobservedthatwhenBi2Se3 andAgare put in contact a chemical reaction occurs at the interface, producing AgBiSe2 and Ag2Se. Interestingly, the reaction already occurs at room temperature, which is not usual for solid-state reactions. In literature this reaction has not been properly described. The authors rather described it as intercalation of the silver atoms, which we have disproved and showed that recrystallization of the new phases occurs. [3,4,5] The results will alsobediscussedincomparisonwithothertwoAg/Bi2Se3 systemsunderourinvestigation:i)Agdepositedby achemicalrouteonBi2Se3 nanoflakesandii)AgdepositedfromavapourphaseinvacuumonaBi2Se3.single crystal
Keywords: topological insulators, topological surface states, solid-state reaction, TI/metal interface
Published in RUNG: 20.08.2021; Views: 2383; Downloads: 0
This document has many files! More...

Re-thinking natural language quantifiers : a novel view integrating formal semantics, pragmatics and psychometrics
Penka Stateva, invited lecture at foreign university

Keywords: quantifier, semantics-pragmatics interface, psychometrics
Published in RUNG: 15.05.2019; Views: 3489; Downloads: 0
This document has many files! More...

The emergence of post-cyclic prosody in loanword integration - Toneless Latinate adjectives in Serbo-Croatian
Marko Simonović, 2012, published scientific conference contribution

Abstract: A case of exceptional assignment of prosody to loanwords is considered. In SerboCroatian, where in loanwords the original position of stress is generally preserved in some way, a small class of Latinate adjectives (e.g., element ‚ arna ¯ ‘elementary’ and person ‚ alna ¯ ‘personal’) become toneless and they display the postcyclic initial falling accent. An account of these data is proposed which combines a new approach to postcyclic prosody, which is shown to go hand in hand with syntactically opaque structures, and a new model of loanword integration, which views the loanword trajectory as lexicalisation. As a result, an enriched theory of both domains and their interaction arises to account for the data and shed some additional light on the position of loanwords in the architecture of the grammar/lexicon.
Keywords: loanword integration, postcyclic prosody, prosody/syntax interface, morphology, lexicon
Published in RUNG: 07.02.2018; Views: 4562; Downloads: 0
This document has many files! More...

The role of syntax in stress assignment in Serbo-Croatian
Boban Arsenijević, Marko Simonović, 2013, independent scientific component part or a chapter in a monograph

Abstract: This chapter analyses a set of interface phenomena showing important correlations between certain phonological regularities on the one hand, and a set of syntactic and semantic properties of the respective expressions on the other. Serbo-Croatian deadjectival nominalizations typically exhibit one of two different prosodic patterns: (1) prosody faithful to the base i.e., surface prosody of the lexical adjective (e.g., Ispraavnoost ‘correctness’, derived from Ispraavan ‘correct’); and (2) a rising span over a long closed penultimate syllable and the syllable following it (e.g., isprAAvnOOst ‘correctness’). The chapter formulates a generalization where, all things being equal, nominalized predicational structures correspond to (1), while nominalized stems correspond to (2). It provides a formal model of the syntactic and semantic as well as the phonological reality of these nominalizations, and an attempt at explaining these facts.
Keywords: deadjectival nominalizations, lexical conservatism, syntax-phonology interface, compositionality, Serbo-Croatian
Published in RUNG: 07.02.2018; Views: 3920; Downloads: 0
This document has many files! More...

Search done in 0.04 sec.
Back to top