Manoj Singh, Lokesh Singh Tanwar and Rupak Banerjee
{"title":"Impact of thermally activated ionic dynamics on the trap-mediated current–voltage characteristics of a mixed-halide hybrid perovskite†","authors":"Manoj Singh, Lokesh Singh Tanwar and Rupak Banerjee","doi":"10.1039/D5TC02146D","DOIUrl":"https://doi.org/10.1039/D5TC02146D","url":null,"abstract":"<p >Organic–inorganic metal halide perovskites (OIMHPs) are at the forefront of leading energy research. Therefore, it is pivotal to understand the effect of operating conditions like temperature, humidity, light exposure, <em>etc.</em> on these materials. The transient ionic dynamics and its effect on the steady-state <em>J</em>–<em>V</em> characteristics of an OIMHP, <em>viz.</em> FAPbBr<small><sub>2</sub></small>I, having a mixed halide composition, were investigated by temperature-dependent dielectric spectroscopy and temperature-dependent space charge limited current (SCLC) measurements in the temperature range of 305–454 K. The contribution of the resistance and capacitance of grains and grain boundaries to the total impedance at different temperatures has been interpreted by analyzing the Bode plots using the Maxwell–Wagner equivalent circuit model. The AC conductivity spectra demonstrate different behaviors in two different temperature regimes. In the low-temperature (LT) regime (323–381 K), the temperature response of ionic conductivity is only dependent on hopping frequency (the ionic carrier concentration factor being temperature-independent), leading to almost similar activation energies of ionic conduction (<em>E</em><small><sub>a</sub></small>) and hopping migration (<em>E</em><small><sub>m</sub></small>), where <em>E</em><small><sub>a</sub></small> = <em>E</em><small><sub>m</sub></small> = 0.30 ± 0.05 eV. However, in the high temperature (HT) regime (395–454 K), we observed a difference in <em>E</em><small><sub>a</sub></small> (0.74 ± 0.05 eV) and <em>E</em><small><sub>m</sub></small> (0.50 ± 0.05 eV) values, which is attributed to the activation energy of mobile charge carrier formation (<em>E</em><small><sub>f</sub></small> = <em>E</em><small><sub>a</sub></small> − <em>E</em><small><sub>m</sub></small> = 0.24 ± 0.05 eV). We propose that the trapped ions in the LT regime are now released by overcoming the barrier <em>E</em><small><sub>f</sub></small> in the HT regime, leading to a substantial increase in the mobile ion concentration. Furthermore, we have unveiled the effect of these mobile ions and trapped carriers on the <em>J</em>–<em>V</em> characteristics in both temperature regimes by analyzing the temperature-dependent SCLC <em>J</em>–<em>V</em> characteristics in the Ag/FAPbBr<small><sub>2</sub></small>I/Ag device configuration. The AC conductivity and electric modulus loss spectra scale to different master curves in the LT and HT regimes, further corroborating the observed thermally activated interplay of ionic conduction and hopping migration. The key findings of this work stimulate more such fundamental investigations of electrical transport in mixed halide OIMHPs and establish their potential in various energy storage applications like batteries, integrated PV-battery/supercapacitor systems, and others.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 29","pages":" 15168-15184"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/tc/d5tc02146d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mercedes Marcos, Alberto Concellón, Almudena Terrel, Rosa I. Merino, Rosa M. Tejedor, Joaquín Barberá, José L. Serrano and Santiago Uriel
{"title":"Halogen-bonded ionic liquid crystals: supramolecular organization and ionic transport†","authors":"Mercedes Marcos, Alberto Concellón, Almudena Terrel, Rosa I. Merino, Rosa M. Tejedor, Joaquín Barberá, José L. Serrano and Santiago Uriel","doi":"10.1039/D5TC01507C","DOIUrl":"https://doi.org/10.1039/D5TC01507C","url":null,"abstract":"<p >Ionic liquid crystals (ILCs) are emerging materials that combine the anisotropic self-assembly of liquid crystals with the ionic conductivity of ionic liquids, making them promising candidates for electrochemical applications such as ion-conducting membranes and next-generation electrolytes. In this work, we report the synthesis and characterization of a series of 1-alkyl-3-halopyridinium halides, where both the cationic and anionic components participate in halogen bonding, leading to enhanced mesophase stability and well-defined ionic nanochannels. Compounds with alkyl chains of 12 carbons or longer exhibit Smectic A liquid crystalline phases, with their stability increasing with chain length and halogen bond strength. X-ray diffraction analysis confirms the role of halogen bonding in driving molecular self-assembly and charge segregation, key factors in mesophase formation. Ionic conductivity measurements demonstrate that these ILCs facilitate ion transport through their nanosegregated ionic domains, with conductivities comparable to other liquid crystalline electrolytes. These findings highlight the potential of halogen-bonded ILCs as functional materials for electrochemical devices, providing a tunable platform for the development of advanced ion-conducting materials.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 28","pages":" 14657-14664"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/tc/d5tc01507c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144646713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Melissa Sophie Egger, Marco Sigl, Robert Saf, Heinz Amenitsch, Ana Torvisco, Thomas Rath and Gregor Trimmel
{"title":"Insights into the thermal decomposition and conversion mechanism of nickel xanthates to nickel sulfides†","authors":"Melissa Sophie Egger, Marco Sigl, Robert Saf, Heinz Amenitsch, Ana Torvisco, Thomas Rath and Gregor Trimmel","doi":"10.1039/D5TC01096A","DOIUrl":"https://doi.org/10.1039/D5TC01096A","url":null,"abstract":"<p >Metal sulfides are promising materials for a wide range of applications, from environmental applications to energy conversion and storage. Like many other transition metal sulfides, nickel sulfide exists in different stoichiometries and phases, which influence their chemical and physical properties. While this feature enables the compound's diversified applications, it also makes it necessary to develop simple and reproducible methods to prepare nickel sulfide with defined composition, phase, and morphology. For metal xanthates, the design of the xanthate ligand allows to tune the properties of the metal sulfide obtained by their thermal conversion. To efficiently tailor the precursor to the application, it is imperative to understand the degradation mechanism of the precursors and the formation of the nickel sulfide phases. In this study, we synthesized a series of nickel xanthates bearing alkyl side chains of varying lengths and branching: methyl, ethyl, <em>n</em>-propyl, iso-propyl, iso-butyl, <em>n</em>-pentyl, neo-pentyl, and <em>n</em>-hexyl. Together with two additional nickel xanthates, we systematically investigated their thermal decomposition behavior and the resulting decomposition products using thermogravimetric analysis with coupled gas chromatography/mass spectrometry, pyrolysis gas chromatography/mass spectrometry, single crystal and powder X-ray diffraction, and grazing incidence wide angle X-ray scattering. Based on these findings, we propose a two-step decomposition mechanism that combines alkyl transfer between the ligands with an extended version of the literature-known Chugaev mechanism, which describes alkene formation from xanthates. This refined mechanism can explain the conflicting degradation products reported in literature so far. Additionally, we studied the influence of the ligand on the formed nickel sulfide using temperature dependent X-ray scattering experiments. The decomposition of the xanthates leads to the initial formation of α-NiS at low temperatures for all the precursors, followed by a phase transformation at higher temperatures. Depending on the precursor both pure α- or β-NiS and various mixed phases can be obtained.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 28","pages":" 14301-14315"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/tc/d5tc01096a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144646733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tian Hu, Xinkuo Li, Jiahe Yan, Yingying Cui, Wei Zhang, Changjian Wang, Xvsheng Qiao and Xianping Fan
{"title":"Heavily doped Ag+ and single pulse nJ laser writable glasses with ionic [YOx] modified covalent Al (PO3)3 networks towards long-term 3D optical data storage†","authors":"Tian Hu, Xinkuo Li, Jiahe Yan, Yingying Cui, Wei Zhang, Changjian Wang, Xvsheng Qiao and Xianping Fan","doi":"10.1039/D5TC01007A","DOIUrl":"https://doi.org/10.1039/D5TC01007A","url":null,"abstract":"<p >Direct laser writing (DLW)-induced photoluminescent Ag clusters in glasses have attracted considerable attention in the development of high-density optical data storage technology. However, achieving silver cluster-doped glasses, with combined advantages of large optical data storage capacities, low writing energy consumption, and ultra-long lifetimes, still remains a big challenge. In this work, with direct near-infrared femtosecond laser writing, silver clusters are formed and enable luminescence read out in aluminum metaphosphate glasses. In order to increase the solubility of Ag in the glass and achieve the above mentioned merits, Y<small><sub>2</sub></small>O<small><sub>3</sub></small> is introduced into the glass system to produce [YO<small><sub><em>x</em></sub></small>] polyhedra and form ionic [YO<small><sub><em>x</em></sub></small>] modified covalent Al(PO<small><sub>3</sub></small>)<small><sub>3</sub></small> glass networks. The combination of a rigid phosphate framework and flexible ionic components gives rise to the transformation of [AlO<small><sub>6</sub></small>] → [AlO<small><sub>4</sub></small>]<small><sup>−</sup></small>, as well as a growing number of nonbridging oxygens (NBOs); then, it results in a more stable glass network. According to the charge compensation strategy, the newly formed negatively charged [AlO<small><sub>4</sub></small>]<small><sup>−</sup></small> tetrahedron can well stabilize silver as Ag<small><sup>+</sup></small>, while silver can also be effectively stabilized by NBO coordination through acting as network modifiers. These eventually improve Ag in the glass to obtain a uniform distribution. Upon the above points, the Y<small><sub>2</sub></small>O<small><sub>3</sub></small> modified aluminum phosphate glass exhibits remarkable fs laser photosensitivity and enables efficient data writing and readout operations only with very low power fs-laser pulses (19 nJ, 0.6 J cm<small><sup>−2</sup></small>). This low-energy requirement significantly reduces power consumption during DLW processes, and the ionic-covalent mixed stable network also endows the glass with long-term endurability. Thus, the glass achieves a storage capacity of 23.3 GB cm<small><sup>−3</sup></small> (equivalent to 790.0 GB for a 120 × 3 mm<small><sup>3</sup></small> Blu-ray DVD) and the laser-written data possess an ultra-long lifetime of up to 5.3 × 10<small><sup>5</sup></small> years at room temperature. Therefore, the glass shows great potential for high density ODS applications.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 30","pages":" 15407-15416"},"PeriodicalIF":5.1,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751173","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}
Hui Xie, Hui Fu, Zhentao Du, Linjie Tong, Jinliang Jiang, Xue Jiang, Jialong Zhao, Weiyou Yang and Jinju Zheng
{"title":"Cr3+-induced broadband near-infrared I combined with near-infrared II emission via rare earth co-doping in Cs2NaInCl6 for multifunctional detection†","authors":"Hui Xie, Hui Fu, Zhentao Du, Linjie Tong, Jinliang Jiang, Xue Jiang, Jialong Zhao, Weiyou Yang and Jinju Zheng","doi":"10.1039/D5TC01593F","DOIUrl":"https://doi.org/10.1039/D5TC01593F","url":null,"abstract":"<p >The increasing need for simultaneous detection of multiple components and precise analysis has driven the search for high-performance, broadband-emitting near-infrared (NIR) materials. Herein, the Cr<small><sup>3+</sup></small>-doped Cs<small><sub>2</sub></small>NaInCl<small><sub>6</sub></small> (CNIC) lead-free double perovskites (DPs) are fabricated by a hydrothermal approach. The as-synthesized DPs exhibit a remarkable photoluminescence quantum yield (PLQY) of 92.41%, with a broad emission spectrum centered at 960 nm and a full width at half maximum (FWHM) of 160 nm. This exceptional performance is attributed to the Cr<small><sup>3+</sup></small> ions with the spin-allowed <small><sup>4</sup></small>T<small><sub>2</sub></small> → <small><sup>4</sup></small>A<small><sub>2</sub></small> transition in a weak crystal field. The CNIC:Cr<small><sup>3+</sup></small> DPs demonstrate not only excellent air and thermal stability but also impressive photostability. Furthermore, Cr<small><sup>3+</sup></small>/Ln<small><sup>3+</sup></small> (Ln<small><sup>3+</sup></small> = Ho<small><sup>3+</sup></small>, Tm<small><sup>3+</sup></small>, and Er<small><sup>3+</sup></small>) co-doped CNIC DPs are employed to achieve multi-peak emissions from NIR I to NIR II by facilitating energy transfer from Cr<small><sup>3+</sup></small> to Ln<small><sup>3+</sup></small>. The optimal PLQYs of the co-doped DPs are found to be 69.34% (Ho<small><sup>3+</sup></small> emission: 14.67%), 79.94% (Tm<small><sup>3+</sup></small> emission: 31.95%), and 71.07% (Er<small><sup>3+</sup></small> emission: 25.88%), respectively. These co-doped DPs have been successfully incorporated into high-performance NIR phosphor-converted light-emitting diodes (NIR pc-LEDs), with promising applications in synchronous multi-substance analysis, biological detection, and food safety monitoring, highlighting their potential for multifunctional applications.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 28","pages":" 14648-14656"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144646786","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}
Yanchen Qiu, Qi Zhang, Ruizhe Wang, Weichu Chen, Xiang Li, Yuwen Zhu, Meifang Zhu, Gang Wang and Hengda Sun
{"title":"3D-printed organic electrochemical transistors on microfluidic paper for multianalyte point-of-care testing†","authors":"Yanchen Qiu, Qi Zhang, Ruizhe Wang, Weichu Chen, Xiang Li, Yuwen Zhu, Meifang Zhu, Gang Wang and Hengda Sun","doi":"10.1039/D5TC01231G","DOIUrl":"https://doi.org/10.1039/D5TC01231G","url":null,"abstract":"<p >Emerging demands for sustainable point-of-care diagnostics drive the development of paper-based organic electrochemical transistors (OECTs), yet challenges persist in achieving multianalyte detection through scalable manufacturing. A low-cost, flexible, and user-friendly multianalyte biosensing platform has been developed by combining three-dimensional microfluidic paper-based analytical devices (μPADs) with 3D printed OECTs. This platform enables the simultaneous detection of multiple essential blood biomarkers, including ions, glucose, and cholesterol. The platform was designed with closed-channels created by removing parts of the cellulose matrix and leaving the bottom of the channel hydrophilic, which significantly increases the instantaneous flow rate by 2.2-fold compared to conventional open-channels. The biofunctionalized OECT sensors demonstrated exceptional sensitivity in the micromolar (μM) range and robust anti-interference capabilities (NR < 0.07 against common interferents), ensuring reliable detection in complex biological samples. This work demonstrates the feasibility of combining direct ink writing (DIW) with paper-based microfluidics, positioning the platform as a viable solution for resource-limited settings and personalized healthcare with capabilities for extended analyte detection and high-density integration.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 28","pages":" 14291-14300"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144646732","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":"Enhancing thermal stability of n-type conduction in carbon nanotubes via cation replacement mediated by bicyclic guanidinium salts†","authors":"Kaho Kawasaki, Mayuko Nishinaka, Yasuko Koshiba, Azumi Akiyama, Qingshuo Wei, Masahiro Funahashi and Shohei Horike","doi":"10.1039/D5TC01263E","DOIUrl":"https://doi.org/10.1039/D5TC01263E","url":null,"abstract":"<p >The development of thermally stable n-type carbon nanotubes (CNTs) is crucial for their implementation in pn junction devices. In previous work, we introduced an ion replacement technique to stabilize chemically p-doped CNTs, demonstrating the control of hole density and the stabilization of doped states through separate doping and anion replacement processes. This study extends the methodologies to n-type doping by substituting the cation with a specific dopant or stabilizer. The exceptional reduction capability of the cobalt-based complex was evident from the negative Seebeck coefficient, the markedly high electrical conductivity, and the reduction in work function of the doped CNTs. Additionally, the selection of the anion is critical for successful cation replacement, as explored through complex chemistry perspectives. The n-type CNTs, coordinated with bicyclic guanidinium cations, showed improved thermal stability compared to their as-doped counterparts. Lastly, we discuss the thermoelectric properties (with the power factor up to 100 μW m<small><sup>−1</sup></small> K<small><sup>−2</sup></small>) as prospective applications for n-type CNTs in energy harvesting. This foundational work proposes a strategy for engineering n-type CNTs with optimized doping levels and enhanced stability.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 27","pages":" 13664-13671"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144598191","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}
Mengran Liu, Chenfei Yang, Shuyu Li, Xiaotao Zhang and Wenping Hu
{"title":"Recent advances in organic stimuli-responsive tunable circularly polarized luminescence materials","authors":"Mengran Liu, Chenfei Yang, Shuyu Li, Xiaotao Zhang and Wenping Hu","doi":"10.1039/D5TC01525A","DOIUrl":"https://doi.org/10.1039/D5TC01525A","url":null,"abstract":"<p >Circularly polarized luminescence (CPL) materials have manifested extensive application prospects in domains owing to their distinctive chiral optical properties, such as three-dimensional display, information encryption and optical sensing. However, conventional CPL materials with fixed emission wavelengths and polarization directions struggle to meet the growing demand for multifunctional materials. In recent years, organic stimuli-responsive tunable CPL materials have attracted significant attention due to their reversible and dynamic properties. These materials can realize the dynamic regulation of the emission wavelength, polarization direction or luminescence efficiency under external stimuli (light, temperature, pH, ions, <em>etc</em>). This review systematically summarizes the design principles, regulatory mechanisms, and potential applications of organic stimuli-responsive tunable CPL materials with different types of stimuli.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 25","pages":" 12584-12611"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144492511","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}
Prakash Govindaraj, Hern Kim and Kathirvel Venugopal
{"title":"Enargite (Cu3AsS4): a ductile mid-temperature thermoelectric material†","authors":"Prakash Govindaraj, Hern Kim and Kathirvel Venugopal","doi":"10.1039/D5TC00351B","DOIUrl":"https://doi.org/10.1039/D5TC00351B","url":null,"abstract":"<p >Despite their intrinsic large band gap, low carrier concentration, and electrical conductivity, sulfide-based thermoelectric materials have been explored extensively because of their abundance and feasibility. This report uncovers the thermoelectric performance of Cu<small><sub>3</sub></small>AsS<small><sub>4</sub></small> by combining density functional theory, the modified Debye–Callaway model, and phonon Boltzmann transport equations. The overall assessment of thermal, mechanical, and dynamical stability is confirmed through the <em>ab initio</em> molecular dynamics simulations, elastic constants, and phonon dispersion computations. The ultra-low lattice thermal conductivity of 0.327 and 1.020 W m<small><sup>−1</sup></small> K<small><sup>−1</sup></small> at 900 K obtained through various approaches can be attributed to the scattering of phonons induced by bonding heterogeneity and large lattice anharmonicity. Also, to improve the reliability of electronic transport properties, the carrier relaxation time is calculated by including acoustic, optical, and impurity phonon scattering mechanisms. The favourable band features and electron and phonon characteristics collectively facilitate a larger optimum power factor accompanied by the figure-of-merit of 1.07 to 2.31 at 900 K for p-type Cu<small><sub>3</sub></small>AsS<small><sub>4</sub></small>. These results highlight the potential applicability of Cu<small><sub>3</sub></small>AsS<small><sub>4</sub></small> for mid-temperature thermoelectric applications. Also, this work elaborates the relationship between physical and mechanical characteristics of the crystal structure, which intensifies the understanding from materials to devices.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 27","pages":" 13986-14000"},"PeriodicalIF":5.7,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/tc/d5tc00351b?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144598130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abhijit Biswas, Sudaice Kazibwe, Shuo Yang, Tymofii S. Pieshkov, Advaith V. Rau, Shreyasi Chattopadhyay, Kathy Lu, Ching-Wu Chu, Tobin Filleter, Liangzi Deng and Pulickel M. Ajayan
{"title":"A mechanically robust, high electrically and low thermally conducting silicon oxycarbide ceramic composite by spark plasma sintering†","authors":"Abhijit Biswas, Sudaice Kazibwe, Shuo Yang, Tymofii S. Pieshkov, Advaith V. Rau, Shreyasi Chattopadhyay, Kathy Lu, Ching-Wu Chu, Tobin Filleter, Liangzi Deng and Pulickel M. Ajayan","doi":"10.1039/D5TC00653H","DOIUrl":"https://doi.org/10.1039/D5TC00653H","url":null,"abstract":"<p >Silicon oxycarbide (SiOC) ceramics derived from pyrolysis of polymer precursors are important for their aerospace, automotive and electronics applications. Here, we investigate the structural and functional properties of a Si–O–C composite obtained <em>via</em> a high-temperature spark plasma sintering process of SiOC powders, derived from the pyrolysis of a polysiloxane polymer. Structural characterization reveals the presence of turbostratic carbon, SiO<small><sub>2</sub></small>, and SiC domains in the Si–O–C matrix composite. Mechanically, it shows a hardness of ∼5.5 GPa and a Young's modulus of ∼40 GPa. The composite shows semiconducting behavior at room temperature with electrical conductivities of ∼95 S cm<small><sup>−1</sup></small> (in-plane) and ∼215 S cm<small><sup>−1</sup></small> (out-of-plane), p-type charges with a carrier density of ∼10<small><sup>21</sup></small> cm<small><sup>−3</sup></small> and a mobility of ∼0.25 cm<small><sup>2</sup></small> V<small><sup>−1</sup></small> s<small><sup>−1</sup></small>, which remains almost temperature independent. The temperature coefficient of resistivity is found to be a very low value of −0.0012 °C<small><sup>−1</sup></small>. We also measured a cross-plane thermal conductivity of ∼1.14 W m<small><sup>−1</sup></small> K<small><sup>−1</sup></small> at 300 K which exhibits temperature-independent behavior. Our observations are valuable for designing oxycarbide ceramic-based energy efficient devices for advanced applications.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 29","pages":" 15051-15058"},"PeriodicalIF":5.7,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/tc/d5tc00653h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}