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Raphael Fortulan, Adam Brown, [Illia Serhiienko](https://orcid.org/0000-0002-3072-9412), [Takao Mori](https://orcid.org/0000-0003-2682-1846), Sima Aminorroya Yamini

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Thermoelectric performance of n-type Bi2S3-alloyed Bi2Te2.7Se0.3Physica B 691 (2024) 416299Available online 16 July 20240921-4526/© 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Thermoelectric performance of n-type Bi2S3-alloyed Bi2Te2.7Se0.3Raphael Fortulan a,b, Adam Brown a, Illia Serhiienko c,d, Takao Mori c,d, Sima AminorroyaYamini a,e,*a Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield, UKb Unconventional Computing Laboratory, University of the West of England, Bristol, UKc International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba, Japand Graduate School of Pure and Applied Science, University of Tsukuba, Tsukuba, Japane School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, 2006, AustraliaA R T I C L E I N F OKeywords:ThermoelectricSulfur addedBi2S3Bismuth telluriden-typeBi2Te2.7Se0.3A B S T R A C TThe effect of isovalent sulfur substitution on the thermoelectric properties of n-type Bi2Te2.7Se0.3 alloy has beenstudied systematically. At low sulfur concentrations, where the samples are single phase, changes in defectchemistry and density of states impacted significantly electrical resistivity and thermopower. Isovalent sulfursubstitution enhanced thermopower and reduced thermal conductivity for both single and multiphase samples.This reduction in thermal conductivity was particularly noticeable in samples containing Bi2S3-based secondaryphase, reaching a low thermal conductivity of ~0.3 W m− 1 K− 1 at 525 K. A maximum figure of merit, zT, of 0.55was achieved for the sample with the highest sulfur content, demonstrating the potential of this approach tooptimise the thermoelectric performance of Bi2Te3-based materials.1. IntroductionAlloys of chalcogenides (Te and Se) and pnictogenides (Bi and Sb)have shown the best performance for low-temperature range powergeneration [1–3]. In particular, binary p-type and n-type compounds arethe best-performing thermoelectric materials at around room tempera-ture [4–10]. The presence of Se at Te sites creates donor levels that in-creases the carrier concentration, and alloying decreases the thermalconductivity [11,12]. The anisotropy of the layered crystal structurealso plays an important role in its efficiency [13,14].The addition of dopants such as Cl [15], Cu [16], Zn [17], I [18], andCuI [19] has been shown to improve the power factor of Bi2Te2.7Se0.3,while nano-precipitates have been proposed to decrease the thermalconductivity and increase thermoelectric efficiency (zT). Recently, therehas been great interest in the isovalent substitution of sulfur for Te sitesin p-type [20,21] and n-type [2,22] bismuth telluride alloys. Sulfur af-fects the naturally occurring antisites and Te vacancies, increasing thecarrier concentration of these alloys [2]. Isovalent sulfur doping hasenhanced both the thermopower and electrical conductivity of Bi2Te2Sethrough modification of the conduction band of this compound, which isvery sensitive to spin-orbit splitting [23], and increased effective mass[24]. The formation of secondary phases owing to the addition of sulfur[25,26] resulted in a decrease in thermal conductivity by introducingmultiscale scattering of phonons [26].Here, we have systematically investigated the effect of Bi2S3 alloyingon the thermoelectric properties of n-type doped Bi2Te2.7Se0.3 com-pound. Unlike previous studies that focused either on light sulfur dopingor on the effect of secondary phases on the transport properties of thecompound [2,22], our work systematically explores a wide range ofsulfur concentrations, covering both regimes. At low sulfur concentra-tions, changes in the density of states and defect chemistry significantlyaltered electrical resistivity and thermopower. At higher sulfur con-centrations, above 2.5 %, a Bi2S3-based secondary phase formed in thematrix, remarkably effective at reducing thermal conductivity,approaching theoretical minimum values. This approach allows us toinvestigate the transition from single-phase to multiphase systems andtheir impact on thermoelectric properties. Our study is motivated by thepotential of sulfur to simultaneously modify the electronic structure atlow concentrations and introduce beneficial microstructural changes athigher concentrations. These findings highlight promising strategies toengineer high-performance n-type Bi2Te3-based thermoelectricmaterials.* Corresponding author. School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, 2006, Australia.E-mail address: s.aminorroaya@sydney.edu.au (S. Aminorroya Yamini).Contents lists available at ScienceDirectPhysica B: Condensed Matterjournal homepage: www.elsevier.com/locate/physbhttps://doi.org/10.1016/j.physb.2024.416299Received 9 June 2024; Received in revised form 7 July 2024; Accepted 12 July 2024mailto:s.aminorroaya@sydney.edu.auwww.sciencedirect.com/science/journal/09214526https://www.elsevier.com/locate/physbhttps://doi.org/10.1016/j.physb.2024.416299https://doi.org/10.1016/j.physb.2024.416299https://doi.org/10.1016/j.physb.2024.416299http://crossmark.crossref.org/dialog/?doi=10.1016/j.physb.2024.416299&domain=pdfhttp://creativecommons.org/licenses/by/4.0/Physica B: Condensed Matter 691 (2024) 41629922. Experiments2.1. Samples fabricationHigh purity elements of bismuth shots (Bi, 99.999 %, Alfa Aesar),tellurium chunks (Te, 99.999 %, Alfa Aesar), selenium shots (Se, 99.999%, Alfa Aesar), and sulfur pieces (S, 99.99 %, Alfa Aesar) were weightedaccording to the stoichiometry of Bi2− y/3Cry/3[(Te2.7Se0.3)1− xSx]1− yClywhere x = (0, 0.003, 0.008, 0.025, 0.05, and 0.2) and y = 0.005. Allsamples are doped with the same concentration of CrCl3 to increase thecharge carrier concentration; for simplification, they are referred to asBi2Te2.7Se0.3 − xBi2S3 throughout the text. Raw elements were loadedinto vacuum-sealed quartz ampules in an inert atmosphere glove boxand sealed under vacuum. The ampules were heated to 850 ◦C, held atthis temperature for 12 h, quenched in cold water, and annealed at450 ◦C for 72 h. The resulting ingots were then ground by hand into finepowders in an agate mortar and pestle in a glove box and sintered undervacuum to produce 11 mm diameter rods using spark plasma sintering(SPS) technique (KCE FCT-H HP D-25 SD, FCT Systeme GmbH, Rauen-stein, Germany) at a pressure of 50 MPa and a temperature of 400 C for4 min. The densities of all samples were measured from the dimensionsand weight of the rods. The average density of the samples wasapproximately 89 % of their theoretical density (see Table S1 for moredetails). The samples exhibited a high ratio of porosity due to the lowactual force applied by the SPS equipment, resulting in an effectivepressure lower than the set one and consequently samples of lowerdensity.2.2. Materials characterizationPowder X-ray Diffraction (PXRD) measurements were conducted ona PANalytical X’Pert Pro diffractometer with Cu–K α 1 radiation (λ =0.15406 nm, 40 kV, 40 mA). The lattice parameters and quantitativephase percentages were determined by the Rietveld refinement methodusing the GSAS-II software [27].2.3. Thermoelectric transport propertiesSimultaneous measurements of electrical resistivity and thermo-power were conducted on an LSR-3 (Linseis) system. Thermal conduc-tivity was calculated as κ = D⋅cp⋅d, where D, cp, and d are the thermaldiffusivity, specific heat capacity, and density, respectively. Thermaldiffusivity was measured by the laser flash analysis (LFA) method usingan LFA 467 HyperFlash, Netzsch. The specific heat capacity was deter-mined using a differential scanning calorimeter (DSC 8000, Perki-nElmer) using the sapphire standard method (ASTM Standard E1269[28]).The room temperature Hall coefficient (RH) measurement was car-ried out on an ECOPIA 3000 Hall Effect Measurement System with amagnetic field of 0.55 T.The longitudinal speed of sound was measured using the pulse-echomethod at room temperature via an ultrasonic thickness gauge (38DLPLUS, Olympus).3. results and discussion3.1. Structural and phase analysisThe PXRD patterns of Bi2Te2.7Se0.3 − xBi2S3, x = (0, 0.003, 0.008,0.025, 0.05, and 0.2) are shown in Fig. 1. All samples showed aBi2Te2.7Se0.3 hexagonal primary phase (space group R3m, PDF Card#050–0954), and samples with x > 0.025 contained an orthorhombiccrystal structure of Bi2S3 secondary phase (space group Pnma, PDF Card#04-014-6675). The estimated phase composition, lattice parameters,and crystallite size are given in Table 1 The small peaks for thesecondary presented in the diffraction patterns of x = 0.025 and 0.05 donot allow for an accurate estimate of the crystallite size of the samples,so they are not reported here.3.2. Electronic transport propertiesThe temperature dependence of electrical resistivity (ρ), thermo-power (α), and thermal conductivity (κ) was measured at the perpen-dicular (in-plane) direction relative to the sintering pressure. Fig. 2(a)–(d) show, respectively, the electrical resistivity, thermopower, powerfactor (PF, α2/ρ), and thermal conductivity of Bi2Te2.7Se0.3 − xBi2S3, x=(0, 0.003, 0.008, 0.025, 0.05, and 0.2) samples. The electrical resistivityof the single-phase samples x = 0 and 0.003 (Fig. 2(a)) shows intrinsicsemiconductor behavior with values decreasing with temperature [29].The electrical resistivity of the multiphase samples with x = 0.025 and0.05 shows the intrinsic behavior as well, whereas the electrical re-sistivity of the sample with x = 0.2 shows a weak metallic behavior witha small positive slope of dρ/dT. The low charge carrier concentrations(Table 2) explain the exhibited intrinsic behavior of these samples.The addition of sulfur to the samples increases the electrical re-sistivity of the samples at concentrations of x= 0.003, 0.008, 0.025, and0.05.The resistivity values reported here are higher than those found inthe literature for Bi2Te2.7Se0.3 [30,31], but similar to those observed inporous samples [32]. Our sintered samples exhibited a relative densityof approximately 89 %, indicating a significant level of porosity. Thishigh porosity plays a crucial role in scattering charge carriers, which inturn reduces their mobility and increase the electrical resistivity [33].Hall effect measurements were performed at 300 K to measure theHall coefficient of the samples and to evaluate their Hall carrier con-centration (nH = 1/(RH ⋅e)) and mobility (μH = RH/ρ), as shown inTable 2. The charge carrier concentration of single-phase alloys (x = 0,0.003 and 0.008) has increased slightly by alloying; however, the carrierconcentration variation of multiphase compounds shows no specifictrend. The observed changes in the carrier concentration of the sulfur-alloyed samples can be explained by the defect control in the system.Bismuth telluride alloys typically exhibit three major atomic defects[16]: (a) antisite defects of Bi at Te sites (BíTe, which contributes onehole per defect); (b) vacancies at Te sites (V⋅⋅Te, which contributes twoelectrons per defect); (c) and vacancies at Bi sites (Vʹ́ʹBi, which contributesthree holes per defect) [34,35] (represented using the Kröger-Vink no-tation [36]). The addition of selenium in these alloys tends to increasethe number of vacancies in Te (V⋅⋅Te) and Se (V⋅⋅Se) since the enthalpy ofevaporation of Se (95.48 kJ mol− 1 [37]) and Te (114.1 kJ mol− 1 [37]) ismuch lower than that of Bi (178.632 kJ mol− 1 [38]); this increases thecarrier concentration of electrons and contributes to the n-type behaviorFig. 1. Powder X-ray diffraction patterns of Bi2Te2.7Se0.3 + xBi2S3 x = (0,0.003, 0.008, 0.025, 0.05, and 0.2). Peaks of Bi2S3 are marked with a bluestar (★).R. Fortulan et al.Physica B: Condensed Matter 691 (2024) 4162993of these materials with high carrier concentrations [39,40]. The lowvalue of the thermopower (Fig. 2(b)) for the sample with x = 0 at roomtemperature (∼ − 12.5 μV K− 1) indicates that vacancy of Te and Se is notthe most prevalent mechanism in our samples, but most likely antisitedefects are responsible for the changes in carrier concentration of singlephase samples in our study [20,41]. For the single-phase samples, thecharge carrier concentration increases with the concentration of sulfur,most likely due to increased sulfur vacancies because of easy evapora-tion of sulfur. However, the mechanism is different for the multiphasesamples. The carrier concentration of multiphase samples(0.025 ≤ x ≤ 0.2) can be described by sulfur defects (V⋅⋅S), which con-tributes to two electrons per defect. This sulfur vacancy in the sulfur-richsecondary phase appears to balanced out the reduction (fractional) ofthe electron-donating defects present in the Bi2Te2.7Se0.3 phase, main-taining a relatively constant carrier concentration. Meanwhile, theunique electronic behavior of the sample with x = 0.2 suggests thathigh-energy donors are accessible from the conduction band of thematrix and contribute to the electronic conduction of this sample. Apossible explanation for this effect is that the interface between the twophases forms an intermediate band of impurity states [42,43].Table 1Phase analysis of Bi2Te2.7Se0.3 + xBi2S3, x = (0, 0.003, 0.008, 0.025, 0.05, and 0.2) obtained from the Rietveld refinement of the powder X-ray diffraction patterns.Bi2Te2.7Se0.3 Bi2S3x . a = b (Å) c (Å) D (μm) wt. % a (Å) b (Å) c (Å) D (μm)0 4.3605(5) 30.2661(19) 0.52 … … … … …0.003 4.3751(4) 30.3880(18) 0.57 … … … … …0.008 43844(7) 30.2565(28) 0.53 … … … … …0.025 4 3492(3) 30.3002(22) 0.6 5.1(4) 11.505(13) 4090(5) 11.142(15) …0.05 4.3600(29) 30.153(15) 0.65 11.6(16) 11.446(30) 4.159(12) 10.687(21) …0.2 4.3733(7) 30.416(5) 0.59 23.0(4) 11.239(10) 4.0609(15) 11.492(8) 0.58Fig. 2. Temperature dependence of the (a) electrical resistivity, (b) thermopower, (c) power factor, and (d) thermal conductivity of Bi2Te2.7Se0.3 − xBi2S3, x = (0,0.003, 0.008, 0.025, 0.05, and 0.2) samples.Table 2Hall carrier concentrations and mobility of Bi2Te2.7Se0.3 + xBi2S3, x= (0, 0.003,0.008, 0.025, 0.05, and 0.2) samples.X nH ( × 1019 cm− 3) μH (cm2 V− 1 s− 1)0 1.57 224.00.003 2.74 81.190.008 2.58 131.00.025 1.42 76.750.05 1.88 73.060.2 7.73 47.55R. Fortulan et al.Physica B: Condensed Matter 691 (2024) 4162994The single-phase sample (x = 0) shows a carrier concentration of1.57 × 1019 cm− 3 and carrier mobility of 224 cm2 V− 1 s− 1 at 300 K. TheHall carrier mobility of samples decreases with the increase in sulfurcontent, reaching the lowest value of 47.55 cm2 V− 1 s− 1 for the multi-phase sample x = 0.2; most likely due to the increased scattering at theinterfaces between phases. On the other hand, the carrier concentrationshows the opposite trend to the resistivity, with its maximum value of7.73 × 1019 cm− 3 for the sample with the highest concentration ofsecondary phase (x = 0.2). This dependence of the carrier concentrationand mobility on the sulfur concentration indicates that the reduction inelectrical conductivity is due to the decrease in carrier mobility, whilethe significant improvement for x = 0.2 is due to the increase in carrierconcentration.The thermopower for all samples has negative values at room tem-perature, indicating n-type conduction (Fig. 2(b)). The linear depen-dence of thermopower to temperature up to 350 K for all samplesindicates that at this temperature range, the main parameter effects onthermopower is the thermal diffusion of electrons, as predicted byMott’s formula [44]. This linear relationship between thermopower andtemperature is observed over the whole measured temperature range forsulfur-free and lightly alloyed samples (x = 0, 0.003, and 0.008).It is well known that the thermopower is strongly dependent on theband structure and the density of states (DOS) around the Fermi level(EF) [45]. Given the high sensitivity of the thermopower values to thesulfur concentration, it can be inferred that the presence of sulfur inthese samples significantly changes the DOS around EF. This significantdependence of the DOS on sulfur content was previously observed in aBi0.5Sb1.5Te3 alloy [41]. The magnitude of the thermopower for sampleswith added sulfur was generally higher than that of the sample withoutsulfur. (∼-12.5 μV K− 1) and ranged from ∼-46.8 μV K− 1 for the samplewith x = 0.008 to ∼-173.9 μV K− 1 for the sample with x = 0.025.Multiphase samples of x = 0.025, 0.05, and 0.2 have the highestvalues of α, comparable to those found in the literature [19], and pre-sented nonlinear behavior at high temperatures, exhibiting bipolarconduction [46]. The presence of additional phases in a material withhighly mismatched band structures can introduce the energy filteringeffect, screening out low energy carriers using a potential barrier that isproportional to the difference in electron affinity of the materials,resulting in an increased thermopower of the bulk material [47].Considering the low values of α for the sulfur-free sample, the powerfactor of all samples with added sulfur is higher than that of thesulfur-free sample (Fig. 2(c)). The combination of low resistivity andrelatively high thermopower of the sample with x = 0.02 resulted in thehighest PF for this sample.In general, the thermal conductivity of the sulfur-containing samplesis lower than that of the single-phase sulfur-free sample, except for thesample with x = 0.008 (Fig. 2(d)).To understand the contribution of phonons and both majority andminority carriers to the heat transport mechanisms in the materials, thetwo-band model, described in the Supporting Information, was used toevaluate the lattice thermal conductivity of these samples. Measuredthermopowers, carrier concentrations, and electrical resistivities wereused to estimate the density of state effective mass, m∗DOS, for both holesand electrons, the deformation potential, Edef , of the conduction andFig. 3. Temperature dependence of the (a) electronic, (b) bipolar, and (c) lattice thermal conductivities (estimated from the two-band model and the Wiedemann-Franz law; detailed in the SI) of Bi2Te2.7Se0.3 − xBi2S3, x = (0, 0.003, 0.008, 0.025, 0.05, and 0.2).R. Fortulan et al.Physica B: Condensed Matter 691 (2024) 4162995valence bands, and the reduced Fermi level. The fitted values for themultiband model are provided in the Supporting Information.The calculated values of the electronic, bipolar, and lattice contri-butions to the total thermal conductivity of samples are shown in Fig. 3(a)–(c), respectively.The electronic thermal conductivity, κe, follows the same behavior ofthe electrical resistivity, with the low resistivity samples showing highervalues of electronic thermal conductivity. The bipolar thermal conduc-tivity values show an exponential increase with temperature due to thethermal activation of minority carriers [46]. The presence of sulfurreduced the values of κbp, with the lowest values for the samples withhigh concentrations of sulfur up to ∼ 450 K, possibly due to the presenceof additional majority carriers in these materials. Care must be taken ininterpreting these results, as these models assume samples assingle-phase alloys, while many thermoelectric materials, includingsome compounds of the current study, contain a substantial ratio ofsecondary phases.The lattice thermal conductivity of sulfur alloyed samples decreasedsignificantly compared to the single-phase sulfur-free sample, except forthe sample with x = 0.008. It is worth noting that this sample has ahigher relative density (~95 %) than other samples (See Table S1 fordetailed densities), resulting in a much higher electrical conductivity(Fig. 2(a)) and consequently electronic contribution to the total thermalconductivity (Fig. 3(a)) of this sample relative to others. This hastherefore resulted to apparent higher lattice thermal conductivity forthis sample in Fig. 3(c).The multiphase sample with the highest sulfur concentration and thelargest proportion of secondary phase, x = 0.2, had a surprisingly lowvalue of κl, approaching Clarke’s limit [48] of κmin ≈ 0.261 W m− 1 K− 1for Bi2Te3 at higher temperatures. The behavior of κl is mainly deter-mined by the phonon-scattering mechanisms that occur in the materials,including phonon-phonon normal/Umklapp process scattering, bound-ary scattering, and pore scattering [49]. The remarkably low values oflattice thermal conductivity in these samples are attributed to: therelatively high porosity values due to the low density of the sinteredsamples, which created additional scattering centers [50,51]; and thepresence of a secondary phase, which created additional boundaryscattering.3.3. Figure of merit, zTThe temperature dependence of the thermoelectric figure of merit(zT) for samples of Bi2Te2.7Se0.3 − xBi2S3, x = (0, 0.003, 0.008, 0.025,0.05, and 0.2), are shown in Fig. 4.The zT values of sulfur-added Bi2Te2.7Se0.3 samples increase signif-icantly compared to sulfur-free samples. Notably, the maximum zT valueof approximately 0.55 is achieved for the sample with x = 0.2. Thisenhancement in zT is attributed to the concurrent improvement in thethermopower and a reduction in the thermal conductivity. Despiteconsiderable improvement of zT values for sulfur-added samplescompared to sulfur-free compound, the zT value of our samples remainrelatively low compared to the samples with similar compositions re-ported in the literature that reached zT of up to 1.2 [16,30,52–59].Although, we are confident that low efficiency of our samples is due totheir low relative density, we have compared the efficiency of our bestsample with the literature, using a raincloud plot of zT values forBi2Te2.7Se0.3-based compounds at temperatures of 300 K, 400 K, and500 K (Fig. 5). These values were obtained from an open database formaterials, Starrydata [60], using a Python API. The plot includes valuesof our Bi2Te2.7Se0.3 + 0.2 at.% Bi2S3 sample.The zT values of our sample is located at the minimum values of thedataset at room temperature and increases towards the lower quartile ofthe data at higher temperatures of 400 K and 500 K. Notably, the dis-tribution of zT values in the literature are heavy tailed with a largespread of values, specifically at 400K, indicating that our data is not anoutlier. Although the average zT values show an upward trend fromroom temperature and reduction at 500K, the efficiency of our sampleremained relatively constant over the measured temperature range.The primary factor contributing to low zT values in this study is thelow density of samples, which led to high electrical resistivity. However,our samples were prepared at the same conditions, which allowed us tostudy the effect of added Bi2S3 on the transport electronic properties ofthese samples regardless of their relatively high porosity.4. ConclusionHere, Bi2Te2.7Se0.3 compound was systematically alloyed with Bi2S3demonstrating improved thermoelectric properties, especially formultiphase compounds. In lightly alloyed samples (x ≤ 0.008), sulfurchanged the density of states and defect chemistry, significantlyaffecting the electrical resistivity and thermoelectric power. At highersulfur concentrations (x≥ 0.025), a Bi2S3-based secondary phase formedand significantly improved the thermopower from − 12.5 μV K− 1for theFig. 4. Temperature dependence of zT for Bi2Te2.7Se0.3 + xBi2S3, x = (0, 0.003,0.008, 0.025, 0.05, and 0.2) samples.Fig. 5. The zT values of Bi2Te2.7Se0.3-based samples obtained from the Star-rydata open database [60] (presented in grey), compared with our sample ofBi2Te2.7Se0.3 − 0.2 Bi2S3 (marked with orange stars (★)) at temperatures of 300K, 400 K, and 500 K. Data is shown as a raincloud plot, showing the raw data,calculated boxplots, and estimated density distributions.R. Fortulan et al.Physica B: Condensed Matter 691 (2024) 4162996sulfur-free sample to − 173.9 μV K− 1 for x= 0.025, likely due to impurityband formation at phase interfaces. This secondary phase also effec-tively reduced the thermal conductivity, with the x = 0.2 samplereaching a remarkably low lattice thermal conductivity of ~0.3 W m− 1K− 1 at 525 K, approaching the theoretical minimum of Bi2Te3. Overall,sulfur alloying successfully reduced thermal conductivity whileincreasing thermal performance in both single-phase and multi-phasesamples, achieving a maximum zT of 0.55 for x = 0.2 compared to~0.05 for the sulfur-free sample.These results highlight the potential of isovalent sulfur substitutionand secondary phase formation as promising strategies to improveBi2Te3-based thermoelectric materials, potentially leading to moreefficient devices for waste heat recovery and cooling applications.CRediT authorship contribution statementRaphael Fortulan: Writing – original draft, Visualization, Valida-tion, Software, Investigation, Formal analysis, Data curation. AdamBrown: Investigation, Data curation. Illia Serhiienko:Writing – review& editing, Investigation, Data curation. Takao Mori:Writing – review&editing, Funding acquisition. Sima Aminorroya Yamini: Writing – re-view & editing, Validation, Supervision, Resources, Project adminis-tration, Methodology, Investigation, Funding acquisition,Conceptualization.Declaration of competing interestThe authors declare the following financial interests/personal re-lationships which may be considered as potential competing interests:Sima Aminorroaya Yamini reports financial support was provided byHenry Royce Institute for Advanced Materials,. Takao Mori reportsfinancial support was provided by JST Mirai Program Grant NumbersJPMJMI19A1. Illias Serhiienko reports financial support was providedby JST SPRING, Grant Number JPMJSP2124. Sima Aminorroaya Yaminireports financial support was provided by Europe Horizons. If there areother authors, they declare that they have no known competing financialinterests or personal relationships that could have appeared to influencethe work reported in this paper.Data availabilityData will be made available on request.AcknowledgmentsThis study was supported by the European Union’s Horizon 2020research and innovation program under the Marie Skłodowska-CurieGrant Agreement No. 801604. This work also received support from theHenry Royce Institute for Advanced Materials, funded through EPSRCgrants EP/R00661X/1, EP/S019367/1, EP/P025021/1, and EP/P025498/1. TM would like to thank JST Mirai Program Grant NumberJPMJMI19A1. IS was supported by JST SPRING, Grant NumberJPMJSP2124.Appendix A. Supplementary dataSupplementary data to this article can be found online at https://doi.org/10.1016/j.physb.2024.416299.References[1] N.S. Chauhan, S.V. Pyrlin, O.I. Lebedev, L.S.A. Marques, M.M.D. Ramos, T. Maiti,K. Kovnir, B.A. Korgel, Y.V. 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