Materials Today Physics最新文献

{"title":"Reducing oxygen vacancies of MoO3 by polyaniline functionalization for stable and efficient inorganic tri-brominated perovskite solar cells","authors":"Wenjing Jiao ,&nbsp;Benlin He ,&nbsp;Ziyu Wang ,&nbsp;Shouhao Sun ,&nbsp;Meng Wei ,&nbsp;Weilin Liu ,&nbsp;Mingran Sun ,&nbsp;Haiyan Chen ,&nbsp;Haiyan Li ,&nbsp;Jialong Duan ,&nbsp;Qunwei Tang","doi":"10.1016/j.mtphys.2024.101514","DOIUrl":"10.1016/j.mtphys.2024.101514","url":null,"abstract":"<div><p>The photovoltaic performance of perovskite solar cells (PSCs) is closely dependent on the efficient carrier extraction and transport at the interface. Here, a polyaniline (PANI) functionalized MoO₃ (PANI/MoO₃) hole transport material (HTM) is exploited to perfect the interface between the perovskite layer and carbon electrode in all-inorganic CsPbBr₃ PSCs. After functionalization with PANI, the p-type behavior and the hole mobility and conductivity of MoO₃ are improved by reducing the oxygen vacancies, which boosts the hole extraction and transport, energy level arrangement at the interface of CsPbBr₃ perovskite/(PANI/MoO₃) HTM. Meanwhile, the PANI/MoO₃ with rich C–N and N–H groups introduced by PANI passivates the ions trap states of perovskite films by the C–N⋯Pb²⁺ (Cs⁺) Lewis acid-base coordination and the N–H⋯Br⁻ hydrogen bonding, leading to an effective suppression of non-radiative recombination for improved carrier extraction. As a result, the PANI/MoO₃ HTMs-based CsPbBr₃ PSCs obtain a remarkably increased power conversion efficiency of 10.41 %, in comparison with the efficiency of the original device (6.55 %). In addition, the unencapsulated device with PANI/MoO₃ HTMs shows excellent long-term stability with 93.9 % maintenance of the initial efficiency after storing in air with 85 % relative humidity and at 85 °C for 30 days.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101514"},"PeriodicalIF":10.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fermi energy modulation by tellurium doping of thermoelectric copper(I) iodide","authors":"Martin Markwitz ,&nbsp;Peter P. Murmu ,&nbsp;Song Yi Back ,&nbsp;Takao Mori ,&nbsp;John V. Kennedy ,&nbsp;Ben J. Ruck","doi":"10.1016/j.mtphys.2024.101513","DOIUrl":"10.1016/j.mtphys.2024.101513","url":null,"abstract":"<div><p>Copper(I) iodide (CuI) is the leading inorganic <span><math><mrow><mi>p</mi></mrow></math></span>-type transparent conductor, attracting major attention for its promising optoelectronic properties and facile growth methods, although, commercial uptake is limited due to its as-of-yet insufficient electrical conductivity. Doping CuI with the chalcogens (O, S, Se, Te) is a viable route to tune its electrical conductivity for applications such as in thin film transistors, hole transport layers in solar cells, and transparent thermoelectric generators. The heaviest chalcogen element, Te, is yet to be explored in heavily intrinsically <span><math><mrow><mi>p</mi></mrow></math></span>-type doped CuI at non-alloying concentrations, the subject of the present work. We report the effects of tellurium at the boundary between the doping and alloying regime (up to a maximum of 2.4 % Te) in CuI thin films and investigation the variation in the thermoelectric properties and electronic band structure of the material. Ion implanting tellurium into CuI led to a progressive reduction in the films' work functions from 4.9 eV to 4.5 eV while the ionization potential remained unchanged, measured through photoemission spectrometry. This signified a modulation of the Fermi energy relative to the valence band edge, having a major effect on the materials' electrical conductivity and Seebeck coefficient, the former decreasing by 3 orders of magnitude, while the latter increased by 80 %. We conducted density functional theory (DFT) calculations to elucidate the effect of tellurium doping on the band structure of CuI. Tellurium doping corroborated the shift of Fermi energy, the incorporation of impurity acceptor states deeper into the band gap, in addition to disordering the valence band maximum. This work shows that, the Fermi energy in heavily <span><math><mrow><mi>p</mi></mrow></math></span>-type doped CuI can be moved away from the valence band through Te doping in addition to introducing band disorder, useful for controlling the hosts’ transport properties.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101513"},"PeriodicalIF":10.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141703688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced visible light harvesting in dye-sensitized solar cells through incorporation of solution-processable silver plasmons and anthracite-derived graphene quantum dots","authors":"Akshatha A. Rao,&nbsp;Santhosh Narendhiran,&nbsp;Manoj Balachandran","doi":"10.1016/j.mtphys.2024.101512","DOIUrl":"https://doi.org/10.1016/j.mtphys.2024.101512","url":null,"abstract":"<div><p>The major setback for the enhanced performance of DSSC is the narrow absorption window and the interfacial exciton recombination. Therefore, in this work, the photovoltaic performance of dye-sensitized solar cells has been improved by the synergistic effect of anthracite-derived graphene quantum dots and silver plasmons. GQD and Ag coupled photoanodes were fabricated by a facile solution processable process under room temperature. The as-fabricated DSSC TiO₂/Ag/GQD (TAG) exhibited an enhanced power conversion efficiency of 10.5 % with a current density of 22.40 mAcm⁻² measured under solar irradiation of 100 mWcm⁻² with AM 1.5G. An enhancement surpassing 30.5 % was obtained for the champion cell when compared to the pristine TiO₂ based DSSC. Furthermore, this study emphasizes developing a cutting-edge approach for the high-quality use of fossil fuel-derived graphene quantum dots in energy conversion systems, thereby encouraging the green conversion of fossil fuels and broadening the potential of anthracite coal's utilization in energy conversion applications.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101512"},"PeriodicalIF":10.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141605918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Janus film coupling radiative cooling and heating for all-day active/passive personal thermal management","authors":"Xin Meng,&nbsp;Qi Zhao,&nbsp;Zhaochuan Chen,&nbsp;Qiang Li,&nbsp;Xuemei Chen","doi":"10.1016/j.mtphys.2024.101511","DOIUrl":"https://doi.org/10.1016/j.mtphys.2024.101511","url":null,"abstract":"<div><p>Textiles with passive radiative cooling (PRC)/passive radiative heating (PRH) capabilities have been developed to address human thermal comfort in different climate scenarios. Although materials with single PRC/PRH function have been reported, they tended to exhibit only one function of either cooling or heating, which was restrictive in achieving efficient and controllable personal thermal management. Herein, we propose a dual-mode Janus film composed of a PVDF-HFP/ZrO₂ cooling layer and a Mxene/CNT heating layer for efficient all-day PRC/PRH. Owing to the natural high refractive index of ZrO₂ nanoparticles and the strong scattering of sunlight by the PVDF-HFP nanofibers, the cooling side exhibits a high solar reflectance of 97.1 %. With an infrared emittance of 93 % in atmospheric window, the cooling side achieves subambient cooling temperatures of 8.8 °C during daytime and 7 °C during nighttime. Meanwhile, the Mxene/CNT synergy enables the heating side to exhibit high solar absorbance and electrical conductivity, resulting in a significant PRH capability of up to 19 °C and an outstanding active Joule heating capability as a temperature compensation. The dual-mode Janus film is able to switch cooling/heating modes by simply flipping the interface to alter the sky-facing side, enabling efficient and continuous personal thermal management in complex and changeable environments.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101511"},"PeriodicalIF":10.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141605805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isotope interface engineering for thermal transport suppression in cryogenic graphene","authors":"Xin Wu ,&nbsp;Yunhui Wu ,&nbsp;Xin Huang ,&nbsp;Zheyong Fan ,&nbsp;Sebastian Volz ,&nbsp;Qiang Han ,&nbsp;Masahiro Nomura","doi":"10.1016/j.mtphys.2024.101500","DOIUrl":"10.1016/j.mtphys.2024.101500","url":null,"abstract":"<div><p>The development of emerging technologies, such as quantum computing and semiconductor electronics, emphasizes the growing significance of thermal management at cryogenic temperatures. Herein, by designing isotope interfaces based on the Golomb ruler, we achieved effective suppression of the phonon thermal transport of cryogenic graphene. The pronounced disordering of the Golomb ruler sequence results in the stronger suppression of thermal transport compared to other sequences with the same isotope doping ratio. We demonstrated that the Golomb ruler-based isotope interfaces have strong scattering and confinement effects on phonon transport via extensive molecular dynamics simulations combined with wave packet analysis, with a proper correction for the missing quantum statistics. This work provides a new stream for the design of thermal transport suppression under cryogenic conditions and is expected to expand to other fields.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101500"},"PeriodicalIF":10.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141597792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation and CALPHAD modeling of thermal conductivities of the Cu–Ag–Cr–Zr system","authors":"Biao Hu ,&nbsp;Chenggang Jin ,&nbsp;Jing Xie ,&nbsp;Yuling Liu ,&nbsp;Xinyue Lan ,&nbsp;Qingping Wang ,&nbsp;Shaoding Sheng","doi":"10.1016/j.mtphys.2024.101502","DOIUrl":"10.1016/j.mtphys.2024.101502","url":null,"abstract":"<div><p>Thermal conductivity is one of the important thermophysical properties for describing the ability of a material to transfer heat. The thermal conductivities and microstructures of Cu–Ag, Cu–Cr and Cu–Zr binary alloys were experimentally investigated. 11 equilibrated binary alloys were designed and prepared annealed at 600 °C for 60 days. Their phase equilibria and compositions were analyzed by scanning electron microscopy with energy dispersive X-ray spectrometry (SEM/EDS), and the thermal diffusivities at 20, 100, 200 and 300 °C and the densities at room temperature were measured by laser flash analysis (LFA) method and Archimedes method, respectively. The heat capacities of alloys at different temperatures were calculated through the thermodynamic database, and then the experimental thermal conductivities of each alloys were obtained by the specific conversion equation. Based on the experimental data from the literature and present work, the thermal conductivities of pure elements, the solid solution phases, the stoichiometric compounds and the two-phase regions were evaluated by the CALPHAD (CALculation of PHAse Diagrams) approach. A set of self-consistent thermal conductivity parameters for description of the Cu–Ag–Cr–Zr system was obtained. Comprehensive comparisons between the calculated and experimental results show that the experimental thermal conductivities were satisfactorily accounted for by the present modeling. The present research results can provide important thermal conductivity information for designing new copper alloys and enrich the thermophysical database of copper alloys.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101502"},"PeriodicalIF":10.0,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141597793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The super raman intensity induced by spin-orbit coupling effect in monolayer MoS2 and WS2 under varying pressures","authors":"Yuan Shang,&nbsp;Yuqiang Wu,&nbsp;Mengtao Sun","doi":"10.1016/j.mtphys.2024.101507","DOIUrl":"10.1016/j.mtphys.2024.101507","url":null,"abstract":"<div><p>Transition metal dichalcogenides (TMDs) are regarded as an optimal material for investigating the quantum effect of Spin-orbit coupling (SOC). Although many experiments have measured the physical properties of TMDs materials, the influence of the SOC effect on these properties cannot be determined. Here, we selected monolayer MoS₂ and WS₂ to investigate their physical properties in both the normal and SOC systems under varying pressures. By comparing the calculated results, the SOC effect significantly influences the effective mass of electrons and holes in the material, it determines the conductive properties of the material. This effect exerts a major influence on the dielectric properties of the material, and also enhances the polarization rate. Meanwhile, we have revised the traditional formula for calculating the raman intensity of symmetric dielectric tensors. The discovery of the super raman intensity effect of TMDs materials induced by the SOC effect has been made. Furthermore, we have discovered and explained how to modulate the TMDs materials in the visible light range to transition into a plasma state at specific wavelengths under pressure, and also reveal the influence of pressure on the strength of characteristic raman modes. The findings of this study provide pioneering theoretical support for the realization of the super raman intensity effect through the quantum effect and pressure manipulation of materials into a plasma state.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101507"},"PeriodicalIF":10.0,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141597794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controlled epitaxial growth of strain-induced large-area bilayer MoS2 by chemical vapor deposition based on two-stage strategy","authors":"Kaiyi Wang ,&nbsp;Ruoyan Xu ,&nbsp;Fenglin Gao ,&nbsp;Shiyao Xu ,&nbsp;Shijie Hao ,&nbsp;Chen Fan ,&nbsp;Yuan Zhang ,&nbsp;Yuehua Wei ,&nbsp;Xiongxiong Xue ,&nbsp;Guolin Hao","doi":"10.1016/j.mtphys.2024.101501","DOIUrl":"10.1016/j.mtphys.2024.101501","url":null,"abstract":"<div><p>Two-dimensional (2D) bilayer transition metal dichalcogenides (TMDCs) have attracted considerable attention due to their promising applications in the fields of electronics, optoelectronics, valleytronics and nonlinear optics. However, the precise synthesis of large-area, high-yield and uniform bilayer MoS₂ semiconductors remains a significant challenge. Herein, we have developed one two-stage chemical vapor deposition strategy based on strain engineering, enabling the controlled preparation of large-area (4 × 6 cm²) bilayer MoS₂ nanostructures. Systematic characterizations indicate that compressive strain was introduced during the growth of first layer MoS₂, which effectively induces the synthesis of the second layer MoS₂. First-principles calculations based on density functional theory further reveal the mechanism of strain induced controllable growth of bilayer MoS₂. Field-effect transistors based on AA and AB stacking bilayer MoS₂ have been fabricated exhibiting excellent electronic properties. Our work provides a new pathway for the precise preparation of bilayer TMDCs nanostructures, offering experimental support for their application in the field of electronic and optoelectronic devices.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101501"},"PeriodicalIF":10.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling interfacial thermal transport in β-Ga2O3/h-BN van der Waals heterostructures","authors":"Soonsung So,&nbsp;Joo-Hyoung Lee","doi":"10.1016/j.mtphys.2024.101506","DOIUrl":"10.1016/j.mtphys.2024.101506","url":null,"abstract":"<div><p>As global power consumption rapidly increases with generation of significant amount of heat, efficient thermal management in electronic equipments becomes an urgent task, which requires a comprehensive understanding on thermal transport in heterostructures within devices. Here, we present detailed examination on the interfacial thermal transport of van der Waals (vdW) heterostructures, composed of <em>β</em>-Ga₂O₃ and hexagonal boron nitride (h-BN) multilayers. Through extensive molecular dynamics simulations, we show that the interfacial thermal conductance (ITC) of <em>β</em>-Ga₂O₃/h-BN system becomes as high as 136.8MWm⁻²K⁻¹, and the high ITC value results from substantial phonon interaction across the interface. In addition to the pristine interface, the effect of structural modulation including strain, vacancies and substitutional defects in h-BN multilayers on the ITC is also analyzed, and it is demonstrated that there exists ranges of strain values and defect concentrations which increase the ITC, and that the enhanced ITC is the result of the interplay among the interfacial distance, the overlap in the phonon density of states and elastic mismatch between <em>β</em>-Ga₂O₃ and h-BN multilayers. These results not only provide insights into understanding interfacial phonon transport in vdW systems but also offer guiding principles for designing efficient heat dissipators in device applications.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101506"},"PeriodicalIF":10.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141597795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase transitions limit lithium adsorption in titanium-based ion sieves","authors":"Hsieh Chen","doi":"10.1016/j.mtphys.2024.101508","DOIUrl":"https://doi.org/10.1016/j.mtphys.2024.101508","url":null,"abstract":"<div><p>Hydrogen titanium oxide (HTO) is a promising material in extracting lithium ions from dilute sources such as geothermal or oil/gas brines. However, experiments show limited Li adsorption in HTO compared to its theoretical maximum capacity, where all H atoms in HTO are replaced by Li that forms lithium titanium oxide (LTO). Here, <em>ab initio</em> molecular dynamics (AIMD) simulations show clear evidence of phase transitions at specific Li adsorption in pure or doped HTO/LTO, which directly predict their experimental maximum capacity. Analysis of thermodynamic properties as well as layered crystal structures show distinct Li-poor to Li-rich phase transitions in the pure, Mo-doped, and Fe-doped HTO/LTO. In addition, it is observed a second phase transition in the Fe-doped HTO/LTO in the Li-poor phases that further constrains Li adsorption. To the best of my knowledge, this is the first study that accurately predict the experimental capacities in ion sieves from first principle. More importantly, this study puts spotlights on phase transitions as an important consideration in molecular engineering developments of functional separation materials, such as the high-performance lithium-ion sieves presented herein.</p></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"46 ","pages":"Article 101508"},"PeriodicalIF":10.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141582280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}