Journal of Materials Chemistry C最新文献

{"title":"Enhanced electrical properties of lead-free sodium potassium niobate piezoelectric ceramics prepared via cold sintering assisted sintering†","authors":"Yao Huang, Xinyue Song, Renbing Sun, Hai Jiang, Peng Du and Laihui Luo","doi":"10.1039/D4TC04031G","DOIUrl":"https://doi.org/10.1039/D4TC04031G","url":null,"abstract":"<p >It is a great challenge to prepare dense (K,Na)NbO<small>₃</small> (KNN)-based ceramics with low volatilization of K<small>⁺</small>/Na<small>⁺</small> ions utilizing a conventional solid state reaction method. Herein, ternary KNNS–BNZS–BZ ceramics were prepared utilizing the conventional solid state reaction sintering (CS) method and the cold sintering-assisted sintering (CSAS) process. The CSAS process was used to prepare discs using KMnO<small>₄</small> solution as a transient melt and held at 225 °C under a uniaxial pressure of 380 MPa for 30 min. The microstructures and piezoelectric properties of the prepared ceramics were investigated. The density and piezoelectric performances of the ceramics prepared <em>via</em> CSAS are much superior to those of the counterparts by the conventional solid-state reaction. The piezoelectric constant <em>d</em><small>₃₃</small> of the CSAS ceramic with strong ferroelectric properties reaches a high value of ∼470 pC N<small>⁻¹</small>. The XRD Rietveld refinement, dielectric–temperature curves and TEM show that the prepared KNNS–BNZS–BZ ceramics have a state of three-phase rhombohedral–orthorhombic–tetragonal (R–O–T) coexistence at room temperature. The enhanced piezoelectric properties of the CSAS ceramics are ascribed to the improved densification and reduced volatilization of K<small>⁺</small>/Na<small>⁺</small> ions by the strategy of CSAS. The present investigation shows that the CSAS method is a potential route for the preparation of KNN-based ceramics.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 1","pages":" 93-102"},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859396","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":"Temperature and locomotion dual self-sensing soft robots based on liquid crystal polymer foams†","authors":"Shuyun Zhuo, Jie Jiang, Yaru Ma, Yiming Chen and Yue Zhao","doi":"10.1039/D4TC03668A","DOIUrl":"https://doi.org/10.1039/D4TC03668A","url":null,"abstract":"<p >Stimuli-triggered actuation and capability of sensing are two important prerequisites for self-sensing soft robots. Currently, liquid crystal polymer (LCP) based soft robots face difficulties in balancing the actuation and sensing in a single device. Here, a promising strategy is reported to design self-sensing robots using LCP foams, which perform actuation and self-sensing simultaneously after alignment and crosslinking. LCP foams are fabricated <em>via</em> controlled solvent vaporization, which feature open cell structures and high porosity, and maintain a reversible actuation strain of 40% in the LC mesogen alignment direction. The crosslinked liquid crystal elastomer foams (LCEFs) show temperature-sensitive resistance after incorporating ionic liquids inside the open cell channels and high tolerance to outside disturbance such as vibration due to the porous microstructure. In addition, the resistive signals during actuation cycles reflect the shape contracting and extending process of the LCEF actuators. Combining the light-triggered reversible actuation and self-sensing, the LCEF-based robot displays real-time feedback on its locomotion details (contraction, extension, and displacement) and temperature.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 3","pages":" 1310-1317"},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142993956","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":"Gate controllable fully spin-polarized and pure spin current in γ-graphyne nanoribbons†","authors":"Liwen Zhang, Yanjing Hao, Yaqing Yang, Jun Chen and Lei Zhang","doi":"10.1039/D4TC03876B","DOIUrl":"https://doi.org/10.1039/D4TC03876B","url":null,"abstract":"<p >Gate-controlled spin-dependent transport has paved the way for spintronic devices with tunable functionalities. In this study, we calculated the spin-dependent transport properties and photocurrent characteristics of a two-probe device based on a zigzag γ-graphyne nanoribbon (γ-GYNR), controlled by gate voltage. We found that adjusting the gate voltage polarity effectively regulated the conduction and blocking of electrons with different spin components. When the gate voltage applied to both leads is positive, a fully spin-polarized current is generated. Furthermore, we observed that a pure spin current and a fully spin-polarized photocurrent could be generated based on the photogalvanic effect. This was explained <em>via</em> the system's symmetry analysis. Our findings indicate an expanded application potential for the zigzag γ-GYNR in generating highly spin-polarized currents. The results highlight not only the unique spin-dependent transport and photocurrent properties of the zigzag γ-GYNR but also its potential for gate-controlled tuning. This research provides a theoretical basis for developing novel γ-GYNR-based spintronic devices, potentially leading to breakthroughs in information storage, quantum computing, and other technologies.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 2","pages":" 884-891"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142918626","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":"Electronic, phononic, and superconducting properties of FeHx (x = 1–6) at 150 GPa†","authors":"Hao Quan, Shi-Na Li, Yu-Lin Han, Jian-Guo Si, Wen-Xue Zhang, Wei-Dong Li and Bao-Tian Wang","doi":"10.1039/D4TC04106B","DOIUrl":"https://doi.org/10.1039/D4TC04106B","url":null,"abstract":"<p >Metal hydrides have been studied extensively due to their intriguing superconductivity and potential hydrogen storage capacities. Here, the structural, electronic, phononic, and superconducting properties of iron hydrides FeH<small>_<em>x</em></small> (<em>x</em> = 1–6) are examined based on density functional theory at a high pressure of 150 GPa. Our calculated formation enthalpy, elastic constants, and phonon spectra indicate that <em>Fm</em><img><em>m</em>-FeH, <em>I</em>4/<em>mmm</em>-FeH<small>₂</small>, <em>Pm</em><img><em>m</em>-FeH<small>₃</small>, <em>Imma</em>-FeH<small>₄</small>, <em>I</em>4/<em>mmm</em>-FeH<small>₅</small>, and <em>P</em>2/<em>c</em>-FeH<small>₆</small> are all dynamically and mechanically stable and may be synthesized in experiments under such conditions. Increasing the hydrogen concentration, the shortest H–H distance is shortened from 2.34 Å (FeH) to 0.73 Å (FeH<small>₆</small>). Meanwhile, the resistance to elastic deformation decreases slightly from FeH to FeH<small>₆</small> and the elastic anisotropies in these systems are evident. Using the Allen–Dynes-modified McMillan equation, the superconducting transition temperatures (<em>T</em><small>_c</small>s) of FeH, FeH<small>₃</small>, and FeH<small>₅</small> are estimated to be 0 K, indicating their conventional metal nature. Excitingly, the <em>T</em><small>_c</small>s of FeH<small>₂</small>, FeH<small>₄</small>, and FeH<small>₆</small> are predicted to be 1.24, 1.50, and 3.35 K, respectively. The electron–phonon coupling (EPC) values of FeH<small>₂</small>, FeH<small>₄</small>, and FeH<small>₆</small> are 0.36, 0.36, and 0.40, respectively, indicating that these three systems are weak conventional superconductors. The EPC in them mainly originates from the Fe-3d orbitals and the vibrations of the Fe atoms. Our results reveal that the content of hydrogen has a significant influence on the electronic, phononic, and superconducting properties of iron hydrides and will supply instructions for exploring new binary or ternary hybrid superconductors at high pressure.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 2","pages":" 928-937"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142918094","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":"Manipulation of electrical performance in Al-based Josephson junctions via oxygen vacancies in barrier†","authors":"Junling Qiu, Shuya Wang, Huihui Sun, Chuanbing Han and Zheng Shan","doi":"10.1039/D4TC03574G","DOIUrl":"https://doi.org/10.1039/D4TC03574G","url":null,"abstract":"<p >Defects in the Al-based Josephson junctions, particularly oxygen vacancy (OV) defects in the barrier, are key determinants for the performance of superconducting qubits, directly limiting the coherence time. However, the effects of OVs with different positions and distributions in the barrier on the performance of Josephson junctions (JJs) remain unclear. Here, we reveal that the electronic structures and transport properties of Al/AlO<small>_<em>X</em></small>/Al JJs are highly dependent on the positions of OVs in the barrier by developing JJ models incorporating different positions, distributions, and numbers of OVs. The OVs in the barrier contribute to improving the conductance of the device. This can be attributed to the fact that the Coulomb repulsion among Al ions in proximity to OVs induces electron delocalization, thereby altering the local density of states in the barrier. Specifically, different positions of OVs can cause variations in electrical properties by several orders of magnitude, when maintaining a fixed number and distribution of OVs. Moreover, the distribution and number of vacancies also affect the electrical properties of JJ to some extent. These results provide theoretical guidance for the study of the microscopic mechanism of JJ with defects, indicating a promising potential for manipulating the performance of JJs.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 47","pages":" 19063-19070"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142777987","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":"Investigation of 3,4-ethylenedioxythiophene and 3,4-dimethoxythiophene as linkage units for multi-dimensional dimeric acceptors†","authors":"Shaohui Yuan, Baofa Lan, Xinyi Ji, Jiaying Wang, Wenkai Zhao, Guankui Long, Xiangjian Wan, Bin Kan and Yongsheng Chen","doi":"10.1039/D4TC03646H","DOIUrl":"https://doi.org/10.1039/D4TC03646H","url":null,"abstract":"<p >Despite the versatile processibility of three-dimensional CH8 series acceptors used in efficient organic solar cells (OSCs), understanding the relationship between the linkage units and performance has been significantly challenging. To address this, we present two dimeric acceptors, CH8-8 and CH8-9, which utilize 3,4-ethylenedioxythiophene and 3,4-dimethoxythiophene as linkage units, respectively, to investigate their effects on molecular properties and device performance. CH8-9 with 3,4-dimethoxythiophene as the central linker exhibited a larger dihedral angle of 37.2° than CH8-8 (23.3°), which is beneficial for avoiding over-aggregation and thus forming a more ideal morphology. Consequently, the morphology of CH8-9 showed a more uniform and smoother surface, leading to enhanced charge transport with more balanced charge-transport mobilities. The resultant PM6:CH8-9-based devices displayed a higher fill factor (FF) and short-circuit current density (<em>J</em><small>_sc</small>), which led to a higher power conversion efficiency (PCE) of 16.3%, surpassing the PCE of the PM6:CH8-8-based device. Our work provides a comprehensive analysis of the impact of incorporating dioxane- and methoxy-substituted thiophene units on device performance, offering insights into optimizing linkage units in multi-dimensional molecules to improve the photovoltaic performance of OSCs.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 2","pages":" 938-944"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142918095","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":"Role of Br–Cl distribution uniformity on the spectral stability of blue emitting mixed-halide perovskites†","authors":"Dan Chen, Yu Mao, Xianglan Huang, Jichen Zhao, Zhiyuan Zhang, Jian Wang and Junbiao Peng","doi":"10.1039/D4TC03780D","DOIUrl":"https://doi.org/10.1039/D4TC03780D","url":null,"abstract":"<p >One of the commonly-held beliefs in quasi-two-dimensional (quasi-2D) bromo–chloride (Br–Cl) mixed-halide perovskite light-emitting diodes (PeLEDs) is that defects are responsible for the poor external quantum efficiency (EQE) and the spectral instability. In our contribution, it's discovered that though the universally employed organic ammonium halide p-F-PEABr enhances EQE, it impairs the spectral stability of the mixed-halide PeLEDs. Further studies have revealed that doping p-F-PEABr into perovskite forms a low-dimensional phase with high Cl-content and a 3D phase with low Cl-content, resulting in a non-uniform Br–Cl distribution. It's demonstrated that the non-uniform distribution of Br–Cl mainly accounts for the spectral instability. The early works which attributed the spectral instability to defects alone unintentionally overlooked the reduction of the low-dimensional phase accompanying the defect passivation. Using organic ammonium halides with weak coordination ability, such as DEABr and DEACl, to passivate defects, can maintain the uniformity of the Br–Cl distribution by preventing the formation of the low-dimensional phase. As a result, both the EQE and spectral stability are enhanced.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 2","pages":" 585-591"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142918594","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":"Concurrent improvements in coercivity and corrosion resistance for Nd6Fe13Ga-reconstructed Nd–Fe–B sintered magnets†","authors":"Rui Shen, Shuainan Xu, Congyi Wang, Enxiang Yang, Xiaolian Liu, Song Fu, Weiyang Jin, Yu Pan, Lizhong Zhao, Pengfei Guan and Xuefeng Zhang","doi":"10.1039/D4TC04062G","DOIUrl":"https://doi.org/10.1039/D4TC04062G","url":null,"abstract":"<p >The grain boundary phase with the chemical composition Nd<small>₆</small>Fe<small>₁₃</small>Ga in Nd–Fe–B sintered magnets has been the subject of considerable research interest due to its role in optimizing grain boundaries; however, it also presents a novel challenge regarding corrosion behavior. In this study, the regulation mechanism of Nd<small>₆</small>Fe<small>₁₃</small>Ga grain boundary-reconstructed magnets with concurrent improvements in coercivity and anti-corrosive properties was investigated. Results indicated that the formed non-ferromagnetic Nd<small>₆</small>Fe<small>₁₃</small>Ga phase and the modified Cu-rich continuous grain boundaries after Nd<small>₆</small>Fe<small>₁₃</small>Ga reconstruction contributed to the promotion of magnetic isolation and a reduction in the corrosion potential difference with the 2 : 14 : 1 phase. The underlying mechanisms of the corrosion behavior were further elucidated through <em>in situ</em> microstructural characterization and first-principles calculations of electron work functions for different phases. This study proposes an effective solution to enhance the magnetic properties and anti-corrosion simultaneously in Nd–Fe–B sintered magnets.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 1","pages":" 373-384"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859354","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":"High-performance circularly polarized photodetectors based on chiral transfer of achiral poly(9,9-dioctylfluorene)†","authors":"Xiaocheng Wu, Junjie Liu, Yunhao Xu, Longzhen Qiu and Xiaohong Wang","doi":"10.1039/D4TC03735A","DOIUrl":"https://doi.org/10.1039/D4TC03735A","url":null,"abstract":"<p >Circularly polarized light (CPL) detection adds a unique dimension to optical information processing and communication, holding great promise for applications in fields such as bioimaging and optical communications. However, the scarcity of suitable active photovoltaic materials for CPL detection has impeded progress in CPL detector development. In this study, a CPL sensing layer was created by annealing-induced chiral transfer of a chiral small molecule (4-[[4-(hexyloxy)benzoyl]oxy]-1,1′-[1,1′-binaphthyl]-2,2′-diester) benzoic acid (S6N) with poly(9,9-dioctylfluorene) (PFO). By designing bilayer-structured devices with a high-performance donor–acceptor conjugated polymer as the charge-transfer layer, organic field-effect transistor detectors capable of CPL differentiation were fabricated, which further solved the problem of poor electrical performance due to the distorted structure of CPL sensing materials. This approach is simple and effective. The resulting high-performance CPL detector demonstrated a strong discriminatory ability for CPL at 405 nm, with a significant photocurrent asymmetry factor (<em>g</em><small>_ph</small>) of 0.58. The detector effectively encoded and transmitted the message “GD” utilizing the Morse code. Moreover, a 3 × 3 device array was assembled to simulate image encryption using the letters “HFUT”. This strategy of blending-induced chiral transfer in combination with bilayer device design provides a direct and efficient route to the development of advanced CPL detectors, which is important for the development of spintronics, cryptography and quantum optics.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 2","pages":" 628-638"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142918533","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 novel broadband near-infrared phosphor Na3Mg4LiSi12O30:Cr3+: moderate synthesis and application†","authors":"Zhenwei Jia, Xiaohui Zhao, Jingyi Gao, Tongqing Sun, Li Wu, Yongfa Kong and Jingjun Xu","doi":"10.1039/D4TC04175E","DOIUrl":"https://doi.org/10.1039/D4TC04175E","url":null,"abstract":"<p >Broadband near-infrared (NIR) phosphors are the key for the preparation of NIR phosphor-converted light-emitting diodes (pc-LEDs), which have great application potential in night vision, medical diagnosis, bioimaging, and food quality analysis. Silicate based NIR phosphors have received wide attention due to their excellent thermal stability, while facing the challenge of being synthesized over 1000 °C. In this study, a novel NIR phosphor Na<small>₃</small>Mg<small>₄</small>LiSi<small>₁₂</small>O<small>₃₀</small>:Cr<small>³⁺</small> (NMLS:Cr<small>³⁺</small>) has been successfully synthesized at 600 °C, and a strong electro-phono coupling effect of Cr<small>³⁺</small> is proved to ensure its broad NIR emission peaking at 785 nm with a full width at half maximum (FWHM) of ∼118 nm. The prepared NIR phosphor is fabricated into a NIR pc-LED, which shows application potential in organizational penetration and night vision. Based on the characteristic absorption of alcohol around 900 nm, a portable NIR detector is designed for alcohol detection. This study provides a suitable low-temperature synthesized host for Cr<small>³⁺</small> doped broadband NIR phosphors and new ideas for exploring advanced applications of NIR luminescent materials.</p>","PeriodicalId":84,"journal":{"name":"Journal of Materials Chemistry C","volume":" 1","pages":" 385-392"},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859356","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}