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1.
Article in English | MEDLINE | ID: mdl-39088726

ABSTRACT

This work demonstrates a physical reservoir using a back-end-of-line compatible thin-film transistor (TFT) with tin monoxide (SnO) as the channel material for neuromorphic computing. The electron trapping and time-dependent detrapping at the channel interface induce the SnO·TFT to exhibit fading memory and nonlinearity characteristics, the critical assets for physical reservoir computing. The three-terminal configuration of the TFT allows the generation of higher-dimensional reservoir states by simultaneously adjusting the bias conditions of the gate and drain terminals, surpassing the performances of typical two-terminal-based reservoirs such as memristors. The high-dimensional SnO TFT reservoir performs exceptionally in two benchmark tests, achieving a 94.1% accuracy in Modified National Institute of Standards and Technology handwritten number recognition and a normalized root-mean-square error of 0.089 in Mackey-Glass time-series prediction. Furthermore, it is suitable for vertical integration because its fabrication temperature is <250 °C, providing the benefit of achieving a high integration density.

2.
Article in English | MEDLINE | ID: mdl-39103240

ABSTRACT

Organometallic tin-oxo-hydroxo cage compounds offer a promising photoresist platform for extreme ultraviolet photolithography (EUVL). Their reactivity is dominated by the facile breaking of the tin-carbon bonds upon photon or electron irradiation. As the cage is dicationic, it exists as a complex with anions for charge compensation. In the present work, we explore the n-butyltin-oxo cage with two tetrakis(pentafluorophenyl)borate counteranions (TinPFPB). In contrast to the small counterions that are typically used, the bulky PFPB anion absorbs a substantial fraction (∼30%) of the impinging EUV radiation (13.5 nm, 92 eV), and it has its own reactivity upon photoionization. When thin films of the complex are irradiated with EUV radiation at low doses, a positive-tone development is possible, which is rather unique as all other known tin-oxo cage resists show a negative tone (cross-linking) behavior. We propose that the initial positive tone behavior is a result of the chemical modification of the Sn cluster by fragments of the borate anions. For comparison, we include the tetrakis(p-tolyl)borate anion (TB) in the study, which has similar bulkiness, and its complex with the n-butyltin-oxo cage (TinTB) shows the usual negative tone EUV resist behavior. This negative-tone behavior for our control experiment rules out a hypothesis based purely on the steric hindrance of the anion as the cause of the different EUV reactivity.

3.
Nanotechnology ; 35(44)2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39111328

ABSTRACT

Sn-doped indium oxide (ITO) semiconductor nano-films are fabricated by plasma-enhanced atomic layer deposition using trimethylindium (TMIn), tetrakis(dimethylamino)tin (TDMASn), and O2plasma as the sources of In, Sn and O, respectively. A shared temperature window of 150 °C- 200 °C is observed for the deposition of ITO nano-films. The introduction of Sn into indium oxide is found to increase the concentration of oxygen into the ITO films and inhibit crystallization. Furthermore, two oxidation states are observed for In and Sn, respectively. With the increment of interfaces of In-O/Sn-O in the ITO films, the relative percentage of In3+ions increases and that of Sn4+decreases, which is generated by interfacial competing reactions. By optimizing the channel component, the In0.77Sn0.23O1.11thin-film transistors (TFTs) demonstrate high performance, includingµFEof 52.7 cm2V-1s-1, and a highION/IOFFof ∼5 × 109. Moreover, the devices show excellent positive bias temperature stress stability at 3 MV cm-1and 85 °C, i.e. a minimalVthshift of 0.017 V after 4 ks stress. This work highlights the successful application of ITO semiconductor nano-films by ALD for TFTs.

4.
Nanomaterials (Basel) ; 14(15)2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39120390

ABSTRACT

This study aimed to investigate the potential of antimony-doped tin oxide (ATO) as a reinforcing agent for polyamide 12 (PA12) in 3D printing by examining four mixtures with varying ATO concentrations (2.0 to 8.0 wt.%, with a 2.0 wt.% interval). These mixtures were used to fabricate filaments for the manufacturing of specimens through the material extrusion method. The mechanical properties of the resulting PA12/ATO composites and PA12 pure samples were evaluated through tensile, Charpy impact, flexural, and microhardness tests. Additionally, rheology, structure, morphology, thermal properties, pore size, and consistency in the dimensions of the samples were evaluated. Thermogravimetric analysis, along with differential scanning calorimetry, scanning electron microscopy, energy-dispersive and Raman spectroscopy, and micro-computed tomography, were conducted. The results were correlated and interpreted. The greatest reinforcement was achieved with the PA12/ATO 4.0 wt.% mixture, which exhibited a 19.3% increase in tensile strength and an 18.6% increase in flexural strength compared with pure PA12 (the control samples). The Charpy impact strength and microhardness were also improved by more than 10%. These findings indicate the merit of composites with ATO in additive manufacturing, particularly in the production of components with improved mechanical performance.

5.
Article in English | MEDLINE | ID: mdl-39111512

ABSTRACT

The presence of the organotin compound tributyltin (TBT) in aquatic ecosystems has been a serious environmental problem for decades. Although a number of studies described the negative impact of TBT on mollusks at different levels, investigations connected to its potential effects during embryogenesis have been neglected. For a better understanding of the impact of TBT on mollusks, in the present study, embryos of previously TBT-treated or not treated specimens of the great pond snail (Lymnaea stagnalis) were exposed to 100 ng L-1 TBT from egg-laying (single-cell stage) until hatching. According to our results, TBT significantly delayed hatching and caused shell malformation. TBT transiently decreased the locomotion (gliding) and also reduced the feeding activity, demonstrating for the first time that this compound can alter the behavioral patterns of molluscan embryos. The heart rate was also significantly reduced, providing further support that cardiac activity is an excellent indicator of metal pollution in molluscan species. At the histochemical level, tin was demonstrated for the first time in TBT-treated hatchlings with intensive reaction in the central nervous system, kidney, and hepatopancreas. Overall, the most notable effects were observed in treated embryos derived from TBT treated snails. Our findings indicate that TBT has detrimental effects on the development and physiological functions of Lymnaea embryos even at a sub-lethal concentration, potentially influencing their survival and fitness. Highlighting our observations, we have demonstrated previously unknown physiological changes (altered heart rate, locomotion, and feeding activity) caused by TBT, as well as visualized tin at the histochemical level in a molluscan species for the first time following TBT exposure. Further studies are in progress to reveal the cellular and molecular mechanisms underlying the physiological and behavioral changes described in the present study.

6.
Chempluschem ; : e202400439, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39140471

ABSTRACT

Organogermane and organostannane compounds are valuable reagents in cross coupling reactions, and copper(I) germanide and stannanide complexes can provide convenient access to these compounds. This review presents the chemistry of copper(I) germanide and stannanide complexes, with a particular focus on systems at the frontier of organic and inorganic chemistry where structural characterisation of coordination complexes facilitates rationalisation of organic mechanisms. These species show both similarities to, and significant divergences from their lighter silanide congeners. For example, they are all viable sources of the relevant organotetranide anion, but in the cases of both germanium and tin, the tetranides can be accessed via direct deprotonation of the corresponding tetranes, a reaction unknown for silicon. Further divergences between copper(I) germanides and stannanides are highlighted; whilst both can be used in productive organic transformations to access organotetranes, catalytic reactions are only reported for germanium. The rather striking ability of triphenlstannides to acts as sources of the phenyl anion are discussed; the mechanism of this reaction is still subject to discussion, but its absence in the chemistry of germanium and silicon is now well-rationalised. We conclude this review by considering potential research directions in the synthesis and exploitation of copper(I) germanides and stannanides.

7.
Article in English | MEDLINE | ID: mdl-39087595

ABSTRACT

We present a new approach to achieve nanoscale transistors on ultrathin flexible substrates with conventional electron-beam lithography. Full devices are first fabricated on a gold sacrificial layer covering a rigid silicon substrate, and then coated with a polyimide film and released from the rigid substrate. This approach bypasses nanofabrication constraints on flexible substrates: (i) electron-beam surface charging, (ii) alignment inaccuracy due to the wavy substrate, and (iii) restricted thermal budgets. As a proof-of-concept, we demonstrate ∼100 nm long indium tin oxide (ITO) transistors on ∼6 µm thin polyimide. This is achieved with sub-20 nm misalignment or overlap between source (or drain) and gate contacts on flexible substrates for the first time. The estimated transit frequency of our well-aligned devices can be up to 3.3 GHz, which can be further improved by optimizing the device structure and performance.

8.
Adv Mater ; : e2407724, 2024 Aug 04.
Article in English | MEDLINE | ID: mdl-39097943

ABSTRACT

All-solid-state lithium-sulfur batteries (ASSLSBs) have attracted intense interest due to their high theoretical energy density and intrinsic safety. However, constructing durable lithium (Li) metal anodes with high cycling efficiency in ASSLSBs remains challenging due to poor interface stability. Here, a compositionally stable, self-lithiated tin (Sn)-carbon (C) composite interlayer (LSCI) between Li anode and solid-state electrolyte (SSE), capable of homogenizing Li-ion transport across the interlayer, mitigating decomposition of SSE, and enhancing electrochemical/structural stability of interface, is developed for ASSLSBs. The LSCI-mediated Li metal anode enables stable Li plating/stripping over 7000 h without Li dendrite penetration. The ASSLSBs equipped with LSCI thus exhibit excellent cycling stability of over 300 cycles (capacity retention of ≈80%) under low applied pressure (<8 MPa) and demonstrate improved rate capability even at 3C. The enhanced electrochemical performance and corresponding insights of the designed LSCI broaden the spectrum of advanced interlayers for interface manipulation, advancing the practical application of ASSLSBs.

9.
Small ; : e2406018, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39101351

ABSTRACT

Although various electrocatalysts have been developed to ameliorate the shuttle effect and sluggish Li-S conversion kinetics, their electrochemical inertness limits the sufficient performance improvement of lithium-sulfur batteries (LSBs). In this work, an electrochemically active MoO3/TiN-based heterostructure (MOTN) is designed as an efficient sulfur host that can improve the overall electrochemical properties of LSBs via prominent lithiation behaviors. By accommodating Li ions into MoO3 nanoplates, the MOTN host can contribute its own capacity. Furthermore, the Li intercalation process dynamically affects the electronic interaction between MoO3 and TiN and thus significantly reinforces the built-in electric field, which further improves the comprehensive electrocatalytic abilities of the MOTN host. Because of these merits, the MOTN host-based sulfur cathode delivers an exceptional specific capacity of 2520 mA h g-1 at 0.1 C. Furthermore, the cathode exhibits superior rate capability (564 mA h g-1 at 5 C), excellent cycling stability (capacity fade rate of 0.034% per cycle for 1200 cycles at 2 C), and satisfactory areal capacity (6.6 mA h cm-2) under a high sulfur loading of 8.3 mg cm-2. This study provides a novel strategy to develop electrochemically active heterostructured electrocatalysts and rationally manipulate the built-in electric field for achieving high-performance LSBs.

10.
Adv Sci (Weinh) ; : e2403835, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38973344

ABSTRACT

Considerable focus on tin-based perovskites lies on substitution to leadhalide perovskites for the fabrication of eco-friendly optoelectronic devices.The major concern related to tin-based perovskite devices are mainly thestability and the efficiency. However, thinking on the final commercializationscope, other considerations such as precursor stability and cost are majorfactors to carry about. In this regard, this work presents a robust and facilesynthesis of 2D A2SnX4 (A = 4-fluorophenethylammonium(4-FPEA); X = I, Br, I/Br) and 3D FASnI3 perovskite microcrystals followinga developed synthesis strategy with low-cost starting materials. In thisdeveloped methodology, acetic acid is used as a solvent, which helps to protectfrom water by making a hydrophobic network over the perovskite surface, andhence provides sufficient ambient and long-term inert atmosphere stability ofthe microcrystals. Further, the microcrystals are recrystallized in thin filmsfor LED application, allowing the fabrication of orange, near-infrared and purered emitting LEDs. The two-step recrystallized devices show better performanceand stability in comparison to the reference devices made by using commercialprecursors. Importantly, the developed synthesis methodology is defined as ageneric method for the preparation of varieties of hybrid tin-based perovskitesmicrocrystals and application in optoelectronic devices.

11.
Angew Chem Int Ed Engl ; : e202407228, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38975669

ABSTRACT

Three functionalized thienopyrazines (TPs), TP-MN (1), TP-CA (2), and TPT-MN (3) were designed and synthesized as self-assembled monolayers (SAMs) deposited on the NiOx film for tin-perovskite solar cells (TPSCs). Thermal, optical, electrochemical, morphological, crystallinity, hole mobility, and charge recombination properties, as well as DFT-derived energy levels with electrostatic surface potential mapping of these SAMs, have been thoroughly investigated and discussed. The structure of the TP-MN (1) single crystal was successfully grown and analyzed to support the uniform SAM produced on the ITO/NiOx substrate. When we used NiOx as HTM in TPSC, the device showed poor performance. To improve the efficiency of TPSC, we utilized a combination of new organic SAMs with NiOx HTM, the TPSC device exhibited the highest PCE of 7.7% for TP-MN (1). Hence, the designed NiOx/TP-MN (1) acts as a new model system for the development of efficient SAM-based TPSC. To the best of our knowledge, the combination of organic SAMs with anchoring CN/CN or CN/COOH groups, and NiOx HTM for TPSC has never been reported elsewhere. The TPSC device based on the NiOx/TP-MN bilayer exhibits great enduring stability for performance, retaining ~80% of its original value for shelf storage over 4000 h.

12.
Heliyon ; 10(12): e33043, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38984312

ABSTRACT

The intrusive bodies in the study area are categorized into two intrusive units, γπK2 and ηoπK2, based on rock structure characteristics and intrusive contact relationships. The primary lithologies are granite porphyry and quartz monzonite porphyry. Through LA-ICP-MS zircon U-Pb dating, the weighted mean ages of zircon ^206Pb/^238U for these two units were determined to be 84.09 ± 0.86 Ma and 86.10 ± 0.76 Ma, respectively. According to geochemical characteristics and Sr-Yb granite classification, the quartz monzonite porphyry is classified as Zhejiang-Fujian type granite, and the granite porphyry as Nanling type granite. The study explores the geodynamic significance of granites in the area based on Sr-Yb granite classification, identifying the lower crust metamorphic facies as amphibolite facies. The source rocks are primarily basic granulites and felsic granulites, reflecting a thermally active lower crust with poorly developed fluids. Additionally, Sr-Yb granite classification aids in determining the crustal thickness of the lower crust, which is crucial for understanding continental geological evolution. This paper discusses the optimal locations and conditions for mineralizing fluid precipitation, noting that tungsten-tin mineralization is associated with Nanling type granites and that the mineralization process generally occurs later than the diagenetic process under conditions of low pressure and low oxygen fugacity. Tungsten-tin prospecting should focus on areas where the surrounding rock temperature ranges from 300 to 500 °C, with particular attention to the contact zones of sedimentary rocks or near structural fault zones.

13.
Environ Pollut ; 358: 124486, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38972563

ABSTRACT

Chlorinated volatile organic compounds (Cl-VOCs) have dramatically biotoxicity and environmental persistence due to the presence of chlorine atoms, seriously jeopardizing ecological security and human health. Dichloromethane (DCM) as a model pollutant, is widely applied in solvents, extractants and cleaning agents in the pharmaceutical, chemical and food industries. In this study, highly biocompatible and conductive carbon cloth-titanium nitride-polyaniline (CC-TiN-PANI) bioelectrodes were obtained for DCM degradation in microbial electrolysis cell (MEC). The good adhesion of TiN and PANI on the electrode surface was demonstrated. The degradation kinetics were fitted by the Haldane model, compared to the CC bioelectrode (0.8 h-1), the proportion of maximum degradation rates to half-saturation concentration (Vmax/Km) of CC-TiN (1.4 h-1) and CC-TiN-PANI (2.2 h-1) bioelectrodes were enhanced by 1.8 and 2.8 times, respectively. Microbial community structure analysis illuminated that the dominant genera on the biofilm were Alicycliphilus and Hyphomicrobium, and the abundance was enhanced significantly with the modification of TiN and PANI. The dechlorination of DCM to formaldehyde could be catalyzed by DCM dehalogenase (DcmA) or by haloalkane dehalogenase (DhlA). And further oxidized to formate: 1) direct catalyzed by formaldehyde dehydrogenase (FdhA); 2) conjugated with glutathione by S-(hydroxymethyl)-glutathione synthase (Gfa), S-(hydroxymethyl)-glutathione dehydrogenase (FrmA) and S-formyl-glutathione hydrolase (FrmB); 3) conjugation with tetrahydrofolate (H4F) and/or tetrahydromethanopterin.

14.
J Colloid Interface Sci ; 675: 792-805, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-39002230

ABSTRACT

Sodium-ion battery (SIB) is one of potential alternatives to lithium-ion battery, because of abundant resources and lower price of sodium. High electrical conductivity and long-term durability of MXene are advantageous as the anode material of SIB, but low energy density restricts applications. Tin phosphide possesses high theoretical capacity, low redox potential, and large energy density, but volume expansion reduces its cycling stability. In this study, tin phosphide particles are in-situ encapsulated into MXene conductive networks (SnxPy/MXene) by hydrothermal and phosphorization processes as novel anode materials of SIB. MXene amounts and hydrothermal durations are investigated to evenly distribute SnxPy in MXene. After 100 cycles, SnxPy/MXene reaches high specific capacities of 438.8 and 314.1 mAh/g at 0.2 and 1.0 A/g, respectively. The capacity retentions of 6.0% and 73.6% at 0.2 A/g are respectively obtained by SnxPy and SnxPy/MXene. The better specific capacity and cycling stability of SnxPy/MXene are attributed to less volume expansion of SnxPy during charge/discharge processes and relieved self-stacking of MXene by encapsulating SnxPy particles between MXene layers. Electrochemical impedance spectroscopy and Galvanostatic intermittent titration technique are also applied to analyze the charge storage mechanism in SIB. Higher sodium ion diffusion coefficient and smaller charge-transfer resistance are obtained by SnxPy/MXene.

15.
ACS Nano ; 2024 Jul 21.
Article in English | MEDLINE | ID: mdl-39033511

ABSTRACT

The development of tin-lead alloyed halide perovskite nanocrystals (PNCs) is highly desirable for creating ultrastable, eco-friendly optoelectronic applications. However, the current incorporation of tin into the lead matrix results in severe photoluminescence (PL) quenching. To date, the precise atomic-scale structural origins of this quenching are still unknown, representing a significant barrier to fully realizing the potential of these materials. Here, we uncover the distinctive defect-related microstructures responsible for PL quenching using atomic-resolution scanning transmission electron microscopy and theoretical calculations. Our findings reveal an increase in point defects and Ruddlesden-Popper (RP) planar faults with increasing tin content. Notably, the point defects include a spectrum of vacancies and previously overlooked antisite defects with bromide vacancies and cation antisite defects emerging as the primary contributors to deep-level defects. Furthermore, the RP planar faults exhibit not only the typical rock-salt stacking pattern found in pure Pb-based PNCs but also previously undocumented microstructures rich in bromide vacancies and deep-level cation antisite defects. Direct strain imaging uncovers severe lattice distortion and significant inhomogeneous strain distributions caused by point defect aggregation, potentially breaking the local force balance and driving RP planar fault formation via lattice slippage. Our work illuminates the nature and evolution of defects in tin-lead alloyed halide perovskite nanocrystals and their profound impact on PL quenching, providing insights that support future material strategies in the development of less toxic tin-lead alloyed perovskite nanocrystals.

16.
ChemSusChem ; : e202400939, 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39034762

ABSTRACT

Fluorine-doped tin oxide (FTO) substrate is an important and expensive component in perovskite solar cells (PSCs), which accounts for up to 40% of a typical PSC raw material cost. In this study, we investigated the recyclability of SnO2/FTO in PSCs by washing the spent PSCs using different solvent such as dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetone, water, and acetone/water mixture. Characterisation of properties of the SnO2/FTO substrates recovered from the PSC show the surface wettability of SnO2/FTO is largely unchanged with water washing while a higher hydrophobicity is obtained with organic solvent washing. Comparison of electronic properties of the SnO2/FTO substrate shows a downward shift of the conduction band by 180 meV with water washing, creating favourable energy alignment with adjacent perovskite for efficient interfacial charge injection. Consequently, PSCs using the water-based recycled SnO2/FTO substrates produced a high power conversion efficiency (PCE) of 19.33% which is comparable to the device using fresh SnO2/FTO substrate (PCE = 19.85%). Furthermore, we demonstrated that the water washing process could retain property of SnO2/FTO substrate for decent PSC performance up to four recycling cycles. This study opens new avenues towards recycling of valuable FTO substrates in PSCs for increased sustainability and cost-effectiveness.

17.
Small ; : e2401891, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39004881

ABSTRACT

Various polytypes of van der Waals (vdW) materials can be formed by sulfur and tin, which exhibit distinctive and complementary electronic properties. Hence, these materials are attractive candidates for the design of multifunctional devices. This work demonstrates direct selective growth of tin sulfides by laser irradiation. A 532 nm continuous wave laser is used to synthesize centimeter-scale tin sulfide tracks from single source precursor tin(II) o-ethylxanthate under ambient conditions. Modulation of laser irradiation conditions enables tuning of the dominant phase of tin sulfide as well as SnS2/SnS heterostructures formation. An in-depth investigation of the morphological, structural, and compositional characteristics of the laser-synthesized tin sulfide microstructures is reported. Furthermore, laser-synthesized tin sulfides photodetectors show broad spectral response with relatively high photoresponsivity up to 4 AW-1 and fast switching time (τ rise = 1.8 ms and τ fall = 16 ms). This approach is versatile and can be exploited in various fields such as energy conversion and storage, catalysis, chemical sensors, and optoelectronics.

18.
Small ; : e2404508, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39007250

ABSTRACT

Here, a phenomenon of efficient oxygen exchange between a silicon surface and a thin layer of tin dioxide during chemical vapor deposition is presented, which leads to a unique Sn:SiO2 layer. Under thermodynamic conditions in the temperature range of 725-735 °C, the formation of nanostructures with volcano-like shapes in "active" and "dormant" states are observed. Extensive characterization techniques, such as electron microscopy, X-ray diffraction, synchrotron radiation-based X-ray photoelectron, and X-ray absorption near-edge structure spectroscopy, are applied to study the formation. The mechanism is related to the oxygen retraction between tin(IV) oxide and silicon surface, leading to the thermodynamically unstable tin(II)oxide, which is immediately disproportionate to metallic Sn and SnO2 localized in the SiO2 matrix. The diffusion of metallic tin in the amorphous silicon oxide matrix leads to larger agglomerates of nanoparticles, which is similar to the formation of a magma chamber during the natural volcanic processes followed by magma eruption, which here is associated with the formation of depressions on the surface filled with metallic tin particles. This new effect contributes a new approach to the formation of functional composites but also inspires the development of unique Sn:SiO2 nanostructures for diverse application scenarios, such as thermal energy storage.

19.
Materials (Basel) ; 17(13)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38998215

ABSTRACT

The ecofriendly tin selenide (SnSe) is expected to find multiple applications in optoelectronic, photovoltaic, and thermoelectric systems. This work is focused on the thermoelectric properties of thin films. SnSe single crystals exhibit excellent thermoelectric properties, but it is not so in the case of polycrystalline bulk materials. The investigations were motivated by the fact that nanostructuring may lead to an improvement in thermoelectric efficiency, which is evaluated through a dimensionless figure of merit, ZT = S2 σ T/λ, where S is the Seebeck coefficient (V/K), σ is the electrical conductivity (S/m), λ is the thermal conductivity (W/mK), and T is the absolute temperature (K). The main objective of this work was to obtain SnSe films via magnetron sputtering of a single target. Instead of common radiofrequency (RF) magnetron sputtering with a high voltage alternating current (AC) power source, a modified direct current (DC) power supply was employed. This technique in the classical version is not suitable for sputtering targets with relatively low thermal and electrical conductivity, such as SnSe. The proposed solution enabled stable sputtering of this target without detrimental cracking and arcing and resulted in high-quality polycrystalline SnSe films with unprecedented high values of ZT equal to 0.5 at a relatively low temperature of 530 K. All parameters included in ZT were measured in one setup, i.e., Linseis Thin Film Analyzer (TFA). The SnSe films were deposited at sputtering powers of 120, 140, and 170 W. They had the same orthorhombic structure, as determined by X-ray diffraction (XRD), but the thickness and microstructure examined by scanning electron microscopy (SEM) were dependent on the sputtering power. It was demonstrated that thermoelectric efficiency improved with increasing sputtering power and stable values were attained after two heating-cooling cycles. This research additionally provides further insights into the DC sputtering process and opens up new possibilities for magnetron sputtering technology.

20.
Materials (Basel) ; 17(13)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38998383

ABSTRACT

This paper aims to investigate the strengthening mechanism of laser shock peening on the interfacial bonding properties between TiN coatings and TC4 titanium alloy substrates. The different surface textures were induced by LSP on a TC4 titanium alloy substrate. Subsequently, titanium nitride (TiN) coatings were deposited on the surface texture. A scratch test and reciprocating sliding wear assessment were conducted to evaluate the impact of LSP on the interfacial bonding properties and wear performance of the coatings. The experimental results demonstrated that the adhesion of TiN coatings deposited on the surface texture formed by laser shock peening was significantly enhanced. The efficacy of laser shock treatment in reducing wear rates was found to be significantly enhanced in cases of both increased spot overlapping rate and increased laser power density. The surface texture created using laser parameters of 6.43 GW/cm2 and a 50% overlapping rate was found to have the most significant effect on improving the adhesion and anti-wear properties of the coating. The laser shock texture was identified as the main contributor to this improvement, providing a large interfacial contact area and a mechanical bond between the coating and the substrate. This bond inhibited the initiation and propagation of micro-cracks caused by the concentration of internal stress and interfacial stress of the coating.

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