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61.
Yiqian Du Zhikai Yan Wenbin You Qiaoqiao Men Guanyu Chen Xiaowei Lv Yuyang Wu Kaicheng Luo Biao Zhao Jincang Zhang Renchao Che 《Advanced functional materials》2023,33(34):2301449
Surface chemistry and interlayer engineering determines the electrical properties of 2D MXene. However, it remains challenging to regulate the surface and interfacial chemistry of MXene simultaneously. Herein, simultaneous modulation of Ti3C2Tx MXene surface termination and layer spacing by alkali treatment are achieved. The electrical and electromagnetic properties of Ti3C2Tx are investigated in detail with respect to KOH and ammonia concentration dependence. A high concentration of KOH caused the Ti3C2Tx layer spacing to expand to 13.7 Å and the surface O/F ratio to increase to 33.84. Because of its weaker ionization effect, ammonia provides finer tuning compared to the drastic intercalation of KOH with a thorough sweeping of the F-containing groups. Ti3C2Tx is enriched with conductive -OH termination after ammonia treatment, which achieves an effective balance with the increased interlayer resistance. Therefore, NH3H2O-Ti3C2Tx achieves broad-band impedance matching and exhibits an efficient microwave loss of −49.1 dB at a low thickness of 1.7 mm, with an effective frequency bandwidth of 3.9 GHz. The results herein optimize the electrical properties of Ti3C2Tx using surface and interfacial chemistry to achieve broad microwave absorption, providing a framework for enhancing the electromagnetic wave loss of intrinsic MXene. 相似文献
62.
Shuo Li Weiyao Han Quan-Fu An Ken-Tye Yong Ming-Jie Yin 《Advanced functional materials》2023,33(38):2303447
Metal–organic frameworks (MOFs) are highly versatile materials that have been identified as promising candidates for membrane-based gas separation applications due to their uniformly narrow pore windows and virtually unlimited structural and chemical features. Defect engineering of MOFs has opened new opportunities for manipulating MOF structures, providing a simple yet efficient approach for enhancing membrane separation. However, the utilization of this strategy to tailor membrane microstructures and enhance separation performance is still in its infancy. Thus, this summary aims to provide a guideline for tailoring defective MOF-based membranes. Recent developments in defect engineering of MOF-based membranes will be discussed, including the synthesis strategies for defective MOFs, the effects of defects on the gas adsorption properties, gas transport mechanisms, and recently reported defective MOF-based membranes. Furthermore, the emerging challenges and future prospects will be outlined. Overall, defect engineering offers an exciting opportunity to improve the performance of MOF-based gas membranes. However, there is still a long way to go to fully understand the influence of defects on MOF properties and optimize the design of MOF-based membranes for specific gas separation applications. Nonetheless, continued research in this field holds great promise for the development of next-generation membrane-based gas separation technologies. 相似文献
63.
Jiayang Liao Xiang Lv Xi-xi Sun Junhua Li Haomin Wang Qiang Chen Hanpeng Lu Duan Wang Jian Bi Jiagang Wu 《Advanced functional materials》2023,33(34):2303637
Although the piezo-catalysis is promising for the environmental remediation and biomedicine, the piezo-catalytic properties of various piezoelectric materials are limited by low carrier concentrations and mobility, and rapid electron-hole pair recombination, and reported regulating strategies are quite complex and difficult. Herein, a new and simple strategy, integrating phase boundary engineering and defect engineering, to boost the piezo-catalytic activity of potassium sodium niobate ((K, Na)NbO3, KNN) based materials is innovatively proposed. Tur strategy is validated by exampling 0.96(K0.48Na0.52)Nb0.955Sb0.045O3-0.04(BixNa4-3x)0.5ZrO3-0.3%Fe2O3 material having phase boundary engineering and conducted the defect engineering via the high-energy sand-grinding. A high reaction rate constant k of 92.49 × 10−3 min−1 in the sand-grinding sample is obtained, which is 2.40 times than that of non-sand-grinding one and superior to those of other representative lead-free perovskite piezoelectric materials. Meanwhile, the sand-grinding sample has remarkable bactericidal properties against Escherichia coli and Staphylococcus aureus. Superior piezo-catalytic activities originate from the enhanced electron-hole pair separation and the increased carrier concentration. This study provides a novel method for improving the piezo-catalytic activities of lead-free piezoelectric materials and holds great promise for harnessing natural energy and disease treatment. 相似文献
64.
Yuntong Guo Zhenyu Chen Jinfeng Ge Jintao Zhu Jinna Zhang Yuanyuan Meng Qinrui Ye Shijie Wang Fei Chen Wei Ma Ziyi Ge 《Advanced functional materials》2023,33(47):2305611
Material design of guest acceptor is always a big challenge for improving the efficiency of ternary organic solar cells (OSCs). Here, a pair of isomeric nonfullerene acceptors based on quinoxaline core, Qx–p-C7H8O and Qx–m-C7H8O, is designed and synthesized. By moving the alkoxy chain attached on side phenyl from meta-position to para-position, both π–π stacking distance and crystallinity are enhanced simultaneously. They obtain the uplifted lowest unoccupied molecular orbital level. Compared to Qx–m-C7H8O, Qx–p-C7H8O exhibits wider absorption spectrum and higher extinction coefficient. Using D18-Cl:N3 as host materials, the addition of guest acceptor Qx–p-C7H8O significantly improves the power conversion efficiency (PCE) from 17.61% to 18.49% because of higher open-circuit voltage (0.875 V) and short-circuit current density (27.85 mA cm−2). This can be attributed to the faster exciton dissociation, more balanced carrier mobility, fine fiber morphology, and lower energy loss in the ternary devices. However, Qx–m-C7H8O-based ternary device achieves relatively low PCE of 17.17% because this device shows extremely low electron mobility. The results indicate that molecular stacking, film morphology, etc., can be effectively modulated by fine-tuning the side chains of guest materials, which may be an effective design rule for further improving the PCE of OSCs. 相似文献
65.
Xiang Lin Jinglin Wang Xiangyi Wu Yuan Luo Yongan Wang Yuanjin Zhao 《Advanced functional materials》2023,33(6):2211323
Marine organisms provide novel and broad sources for the preparations and applications of biomaterials. Since the urgent requirement of bio-hydrogels to mimic tissue extracellular matrix (ECM), the natural biomacromolecule hydrogels derived from marine sources have received increasing attention. Benefiting from their outstanding bioactivity and biocompatibility, many attempts have been made to reconstruct ECM components by applying marine-derived natural hydrogels. Moreover, marine hydrogels have been successfully applied in biomedicine by means of microfluidics, electrospray, and bioprinting. In this review, the classification and characteristics of marine-derived hydrogels are summarized. In particular, their role in the development of biomaterials is also introduced. Then, the recent advances in bio-fabrication strategies for various hydrogel materials are focused upon. Besides, the influences of hydrogel types on their functions in biomedical applications are discussed in depth. Finally, critical reflections on the limitations and future development of marine-derived hydrogels are presented. 相似文献
66.
Yingjie Kong Wenjian Shen Haoyu Cai Wei Dong Cong Bai Juan Zhao Fuzhi Huang Yi-Bing Cheng Jie Zhong 《Advanced functional materials》2023,33(25):2300932
Despite the rapid developments are achieved for perovskite solar cells (PSCs), the existence of various defects in the devices still limits the further enhancement of the power conversion efficiency (PCE) and the long-term stability of devices. Herein, the efficient organic potassium salt (OPS) of para-halogenated phenyl trifluoroborates is presented as the precursor additives to improve the performance of PSCs. Studies have shown that the 4-chlorophenyltrifluoroborate potassium salt (4-ClPTFBK) exhibits the most effective interaction with the perovskite lattice. Strong coordination between BF3−/halogen in anion and uncoordinated Pb2+/halide vacancies, along with the hydrogen bond between F in BF3− and H in FA+ are observed. Thus, due to the synergistic contribution of the potassium and anionic groups, the high-quality perovskite film with large grain size and low defect density is achieved. As a result, the optimal devices show an enhanced efficiency of 24.50%, much higher than that of the control device (22.63%). Furthermore, the unencapsulated devices present remarkable thermal and long-term stability, maintaining 86% of the initial PCE after thermal test at 80 °C for 1000 h and 95% after storage in the air for 2460 h. 相似文献
67.
Coralie Greant Bo Van Durme Jasper Van Hoorick Sandra Van Vlierberghe 《Advanced functional materials》2023,33(39):2212641
Multiphoton lithography (MPL) is a powerful and useful structuring tool capable of generating 2D and 3D arbitrary micro- and nanometer features of various materials with high spatial resolution down to nm-scale. This technology has received tremendous interest in tissue engineering and medical device manufacturing, due to its ability to print sophisticated structures, which is difficult to achieve through traditional printing methods. Thorough consideration of two-photon photoinitiators (PIs) and photoreactive biomaterials is key to the fabrication of such complex 3D micro- and nanostructures. In the current review, different types of two-photon PIs are discussed for their use in biomedical applications. Next, an overview of biomaterials (both natural and synthetic polymers) along with their crosslinking mechanisms is provided. Finally, biomedical applications exploiting MPL are presented, including photocleaving and photopatterning strategies, biomedical devices, tissue engineering, organoids, organ-on-chip, and photodynamic therapy. This review offers a helicopter view on the use of MPL technology in the biomedical field and defines the necessary considerations toward selection or design of PIs and photoreactive biomaterials to serve a multitude of biomedical applications. 相似文献
68.
Yubao Li Jingchao Xiao Xinqi Cao Zhiwei Gu Wei Zhang 《Advanced functional materials》2023,33(17):2213385
Here an IR-heating chemical vapor deposition (CVD) approach enabling fast 2D-growth of WSe2 thin films is reported, and the great potential of metal contact doping in building CVD-grown WSe2-based lateral homojunction is demonstrated by contacting with TiN/Ni metals in favor of holes/electrons injection. Shortening nanosheet channel to ≈2 µm leads to pronounced enhancement in the performance of diode. The fabricated WSe2-based diode exhibits high rectification ratios without the need of gate modulation and can work efficiently as photovoltaic cell, with maximum open circuit voltage reaching up to 620 mV and a high power conversion efficiency over 15%, empowering it as superb self-powered photodetector for visible to near-infrared lights, with photoresponsivity over 0.5 A W−1 and a fast photoresponse speed of 10 µs under 520 nm illumination. It is of practical significance to achieve well-performed photovoltaic devices with CVD-grown WSe2 using fab-friendly metals and simple processing, which will help pave the way toward future mass production of optoelectronic chips. 相似文献
69.
Chaoying Zhang Jiaxing Gong Jingyu Zhang Ziyu Zhu Ying Qian Kejie Lu Siyi Zhou Tianyi Gu Huiming Wang Yong He Mengfei Yu 《Advanced functional materials》2023,33(40):2302251
Autograft replaced by a nerve guidance conduit (NGC) is challenging in peripheral nerve injury because current NGC is still limited by precise conductivity and excellent biocompatibility in vivo, which influences the peripheral nerve repair even for a long lesion gap repair. Several particular elements have the potential function for nerve conductivity acceleration based on the traditional three factors of neural tissue engineering. The review aims to address three questions: 1) What is the superior factor for nerve conduction in the application? 2) How can a more conductive regenerative scaffold be constructed in vivo? 3) What is the next step in nerve regeneration for NGC? The bibliometrics analysis of NGC-related references is adopted to acquire that the conductive material, manufacturing technology of neural scaffold, and electrical stimulation (ES) play essential roles in the acceleration of nerve conduction. This review visually analyses the research status and summarizes the main types of conductive materials, the manufacturing technologies of neural scaffolds, and the characteristics of ES. The viewpoints and outlook of developing NGC are also discussed in this review. The proposed three elements are expected to improve the nerve conduction of NGC in vivo and even address the dilemma of long-distance peripheral nerve injury. 相似文献
70.
Ji Qian Yang Ha Krishna Prasad Koirala Di Huang Zhi Huang Vincent S. Battaglia Chongmin Wang Wanli Yang Wei Tong 《Advanced functional materials》2023,33(22):2205972
The recently developed Li-excess cation-disordered rock salts (DRXs) exhibit an excellent chemical diversity for the development of alternative Co/Ni-free high-energy cathodes. Herein, the synthesis of a highly fluorinated DRX cathode, Li1.2Mn0.6Ti0.2O1.8F0.2, based on cost-effective and earth-abundant transition metals, via a solid-state reaction, is reported. The fluorinated DRX cathode using ammonium fluoride precursor exhibits more uniform particle size and delivers a specific discharge capacity of 233 mAh g−1 and specific energy of 754 Wh kg−1, with 206 mAh g−1 retained after 200 cycles. The combined synchrotron X-ray absorption spectroscopy and resonant inelastic X-ray scattering spectroscopy analysis reveals that the remarkable cycling performance is attributed to the high fluorination and thus enhanced Mn content, enabling the utilization of more Mn redox than the oxide analog. This study demonstrates a great promise to develop next-generation cost-effective DRX cathodes with enhanced capacity retention for high-energy Li-ion batteries. 相似文献