共查询到20条相似文献，搜索用时 0 毫秒
1.
Jin Soo Kang Seoni Kim Dong Young Chung Yoon Jun Son Kyusik Jo Xiao Su Myeong Jae Lee Hwajoo Joo T. Alan Hatton Jeyong Yoon Yung‐Eun Sung 《Advanced functional materials》2020,30(9)
Given that a considerably large population suffers from shortage of water, there are numerous on‐going efforts to turn seawater into freshwater, and electrochemical desalination processes—particularly capacitive deionization (CDI)—have gained significant attention due to their high energy efficiency and reliable performance. Meanwhile, carbonaceous electrode materials, which are most commonly used in CDI systems, have poor long‐term stability due to unfavorable interactions with oxygen in saline water. Herein, rapid and vigorous inversion of surface charges in heteroatom‐doped carbon electrodes, which leads to a robust operation of CDI with high desalination capacity, is reported for the first time. By carbonization of coffee wastes, nitrogen‐ and sulfur‐codoped activated carbon with hierarchical micro/mesopores are prepared in an environmentally‐friendly manner, and this carbon results in a significantly higher inverted capacity than that of various activated carbon counterparts in long‐term CDI operations, without any sign of drop in performance. Investigations on the changes in physicochemical properties of the electrodes during the inversion disclose the favorable roles of nitrogen and sulfur dopants, which can be summarized as enlarging the difference between the surface charges of the two electrodes by chemical interactions with oxygen in the anode and carbon in the cathode. 相似文献
2.
3.
4.
Seungyeon Choi Barsa Chang Seoni Kim Jiho Lee Jeyong Yoon Jang Wook Choi 《Advanced functional materials》2018,28(35)
Capacitive deionization (CDI) that engages porous carbon electrodes constitutes one of the well‐established energy‐efficient desalination methods. However, improvement in desalination performance, including ion removal capacity, ion removal rate, and charge efficiency remains requisite for a wide range of applications. Herein, an ion‐exchange membrane‐free asymmetric CDI is introduced by pairing a metal organic framework (MOF), namely, K0.03Cu[Fe(CN)6]0.65·0.43H2O and porous carbon. The exclusive intercalation of cations into the MOF prevents the reverse adsorption of co‐ions (anions), thus significantly improving ion removal capacity (23.2 mg g?1) and charge efficiency (75.8%). Moreover, by utilizing the advantage of the MOF that diverse mono‐ and divalent cations can be stored in the narrow redox potential range, the asymmetric CDI allows simultaneous capture of mono‐ and divalent cations, thus achieving omnivalent cation removal. Moreover, cations are intercalated in the hydrated forms without a discrete phase transition of the host structure, facilitating rapid desalination by reducing the desolvation energy penalty, which results in a high ion removal rate of 0.24 mg g?1 s?1. This study offers a new design principle in CDI: the integration of a crystal structure with large ionic channels that enable hydrated intercalation of multivalent ions in a fast and exclusive manner. 相似文献
5.
Yujie Gao Cheng Lin Kan Zhang Wenhan Zhou Shiying Guo Wenqiang Liu Lianfu Jiang Shengli Zhang Haibo Zeng 《Advanced functional materials》2021,31(34):2102766
Mono-elemental antimonene as a new member of the 2D material family has recently attracted huge attention, whereas the higher chemical activity and narrower interlayer gallery have impinged the quality of product upon exfoliation from the bulk counterpart. To overcome the intrinsic drawbacks, along with the line of the liquid-phase exfoliation (LPE) method, here, a pressurized alloying approach introduces a Li3Sb alloy intermediate at the edge region of bulk β-phase antimony by pre-lithiation in the presence of n-butyllithium and internal pressure is put forward. A protonation process converts the Li3Sb to gaseous stibine (SbH3) in a liquid solution, enabling an upward buoyancy together with the endothermic opening of the galleries that facilitate the subsequent LPE. As a result, the β-phase antimony is efficiently exfoliated into antimonene nanosheets with perfect retention of basal plane texture (lateral size of ≈3 µm and thickness of less than 2 nm). Finally, the high-quality antimonene being simply treated with HCl enables great Na+ diffusion along the basal plane to deliver excellent capacitive deionization performance with a salt adsorption capacity of 31.4 mg g–1 at an ultra-low NaCl concentration (135 mg L–1). 相似文献
6.
Zhi‐Yu Yang Lin‐Jian Jin Guo‐Qian Lu Qing‐Qing Xiao Yu‐Xia Zhang Lin Jing Xiao‐Xue Zhang Yi‐Ming Yan Ke‐Ning Sun 《Advanced functional materials》2014,24(25):3917-3925
Capacitive deionization (CDI) is a competent water desalination technique offering an appropriate route to obtain clean water. However, a rational designed structure of the electrode materials is essentially required for achieving high CDI performance. Here, a novel sponge‐templated strategy is developed for the first time to prepare graphene sheets with high specific surface area and suitable pore size distribution. Sponge is used as the support of graphene oxide to prevent the restack of graphene sheets, as well as to suppress the agglomerate during the annealing process. Importantly, the as‐fabricated graphene sheets possess high specific surface area of 305 m2 g?1 and wide pore size distribution. Ultrahigh CDI performance, a remarkable electrosorptive capacity of 4.95 mg g?1, and siginificant desorption rate of 25 min, is achieved with the sponge‐templated prepared graphene electrodes. This work provides an effective solution for the synthesis of rational graphene architectures for general applications in CDI, energy storage and conversion. 相似文献
7.
Water Treatment: Sponge‐Templated Preparation of High Surface Area Graphene with Ultrahigh Capacitive Deionization Performance (Adv. Funct. Mater. 25/2014) 
下载免费PDF全文
下载免费PDF全文 Zhi‐Yu Yang Lin‐Jian Jin Guo‐Qian Lu Qing‐Qing Xiao Yu‐Xia Zhang Lin Jing Xiao‐Xue Zhang Yi‐Ming Yan Ke‐Ning Sun 《Advanced functional materials》2014,24(25):3838-3838
8.
选用常见的生物质萝藦壳作为碳源,并采用水热碳化法和化学活化法,通过K2CO3和KOH进行活化后,分别得到多孔碳材料并命名为MPJ-KCO和MPJ-KO,与不使用活化剂的样品MPJ-CB进行对比,MPJ-KO具有丰富的微孔和介孔,且比表面积达到1586 m2/g。在扫描速率5 mV/s下,MPJ-KO电极比电容达149.9 F/g。在电容去离子(CDI)脱盐实验中,MPJ-KO电极脱盐量达到16.20 mg/g。通过这项研究,不仅可以最大化废弃生物质的价值,还提供了其在CDI脱盐中的潜在应用。 相似文献
9.
Kaustub Singh Guanna Li Juhan Lee Han Zuilhof B. Layla Mehdi Rafael L. Zornitta Louis C. P. M. de Smet 《Advanced functional materials》2021,31(41):2105203
Selective removal of ions from water via capacitive deionization (CDI) is relevant for environmental and industrial applications like water purification, softening, and resource recovery. Prussian blue analogs (PBAs) are proposed as an electrode material for selectively removing cations from water, based on their size. So far, PBAs used in CDI are selective toward monovalent ions. Here, vanadium hexacyanoferrate (VHCF), a PBA, is introduced as a new electrode material in a hybrid CDI setup to selectively remove divalent cations from water. These electrodes prefer divalent Ca2+ over monovalent Na+, with a separation factor, βCa/Na ≈3.5. This finding contrasts with the observed monovalent ion selectivity by PBA electrodes. This opposite behavior is understood by density functional theory simulations. Furthermore, coating the VHCF electrodes with a conducting polymer (poly-pyrrole, doped with poly-styrenesulphonate) prevents the contamination of the treated water following the degradation of the electrode. This facile and modular coating method can be effortlessly extended to other PBA electrodes, limiting the extent of treated water contamination during repeated cycling. This study paves the way for tunable selectivity while extending the library of electrodes that can be successfully used in (selective) CDI. 相似文献
10.
Adekunle Adedapo Obisanya;Liang Ma;Jinkang Liu;Tianshuo Yang;Zhibin Ren;Xinyi Tan;Faming Gao;Jianren Wang; 《Advanced functional materials》2024,34(44):2404591
Prussian blue analogues (PBAs) are a class of promising materials for capacitive deionization. However, the kinetic mismatch between their slow ion storage rate and the demand from short-time desalination severely limits their desalination performance. Here, a group of structure-tuneable Ni-Mn PBAs have been developed by a combination strategy of surface-protected chemical etching and Ostwald ripening to study their ion storage kinetics. Treating them as demos, the characterizations and investigations, e.g., in situ XRD in a three-electrode system, dynamic impedance, finite element simulation, and DFT calculations etc., reveal that the slow ion diffusion caused by the severe agglomeration of the nanoparticles and the unsuitable lattice parameter controls the final desalination behavior. Therefore, the correspondingly optimized sample (HC-t) possessing a microscale hollow structure, nanoscale shell thickness, and expanded lattice, displays a fast ion storage kinetics with the ratio of surface-controlled current as high as 82% at a scan rate of 20 mV s−1. Consequently, it delivers an impressive desalination capacity of 120.8 mg g−1 (2.06 mmol g−1 Na+) with a fast average desalination rate of 0.25 mg g−1 s−1 (0.004 mmol g−1 s−1) at 1.2 V, competitive with those reported in the literature. Moreover, the elucidation of the structure-performance correlation provides valuable insights for the development and design of next-generation PBAs for capacitive deionization (CDI). 相似文献
11.
Sebastian Bernhard Rauer Siqi Wang Niklas Köller Daniel Josef Bell Yunpeng Zhang Xuejiao Wang Christian J. Linnartz Matthias Wessling John Linkhorst 《Advanced functional materials》2023,33(38):2303606
Activated carbon (AC) particles constitute the current material of choice concerning the preparation of flow electrodes for flow-electrode capacitive deionization (FCDI). They are inexpensive, mass-producible, highly conductive, and exhibit a large specific surface area for ion adsorption. However, despite recent advances concerning the modification of AC slurries, their density, and hydrophobicity still constitute major challenges regarding particle aggregation, sedimentation, and pumpability, restricting their particle load to approximately 25 wt.%. Since the particle volume fraction directly correlates to the chance of particle contact, which dictates the charge transfer and hence the degree of flow electrode utilization, the development of AC-based slurries seems to stagnate. This study addresses these challenges by investigating poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)-based suspensions as an alternative to conventional carbon-based flow electrodes. The corresponding conductive hydrogel particles feature softness, internal porosity, low density, hydrophilicity, and a mass-specific salt adsorption capacity that exceeds AC by up to ten times. FCDI experiments can reveal that, contrary to AC, the inherent properties of PEDOT:PSS-based particles simplify the slurry preparation process and enable flow electrode circulation at significantly higher particle volume fractions. These results suggest that PEDOT:PSS-based hydrogel particles are a promising candidate to overcome the percolation and contact-related challenges of state-of-the-art AC slurries. 相似文献
12.
Faradaic capacitive deionization (FCDI) with attractive ion-capture capacity, outstanding durability, and potential compatibility in high-salinity water has been recognized as the robust alternative to address the alarming freshwater scarcity. The further innovation of boosting electrode materials is the indispensable requisite for highly efficient FCDI application. Herein, a low-crystalline nitrogen-doped carbon quantum dots modified Mg2+-pillar preintercalated V3O7 (i.e., NCQDs/Mg-V3O7) heterostructure is assembled via an ingenious one-spot hydrothermal avenue, and is investigated as the advanced FCDI electrode for desalination application. Taking advantages of the synergic effect of unique microstructure, improved electronic conductivity, and exceptional structural durability, the NCQDs/Mg-V3O7 electrode delivers an admirable gravimetric adsorption capacity of 54.32 mg g−1 in a NaCl solution of 1500 mg L−1 and attractive cyclic durability. Further, density functional theory calculations verify the intense interface electron coupling interaction between tri-components, enabling the significantly promoting Na+ capture capability. The synergy removal mechanism is clarified by ex-situ X-ray photoelectron spectroscopy and in-situ Raman tests. Additionally, the average removal efficiency of hybrid electrode attains 93.75% in the simulated wastewater comprising the NaCl of 50 mg L−1 and diverse metal nitrates from 10 to 100 mg L−1 for each, certifying the great prospects for practical wastewater treatment. 相似文献
13.
Yuan Yu Shuzhao Pei Jinna Zhang Nanqi Ren Shijie You 《Advanced functional materials》2023,33(26):2214725
Porous electrodes offer a new opportunity for flow-through electrochemical water purification, but their irregular porous-structure makes the local flow pattern and mass transfer performance inhomogeneous, unpredictable, and uncontrollable. In this study, a bio-inspired design is reported for porous electrode by learning the micro-scale architectures of the wings of butterfly and owl based on analogy between heterogeneous mass transfer and sound absorption. Results demonstrate that combining gyroid and perforated plate can produce strong periodic vortex and inertial flow in interpenetrating channels even at laminar flow region. This enables homogeneous, predictable and controllable flow patterns and enhanced mass transfer, which can be explained by uniformity analysis and physical field synergy. Based on experimental tests on Cu electrode fabricated by selective laser melting, the composite gyroid electrode generates the limiting current density of 83% higher than random porous-structured electrode, accounting for nitrate removal as high as 95% by electrochemical denitrification. This study represents a paradigm shift to advance design for porous architectures by learning experiences of hydrodynamic behaviors from nature. In this way, it is feasible to enhance mass transfer by modifying local flow patterns on pore scale, which may have broader implications that extend to other heterogeneous reaction systems. 相似文献
14.
MEMS高精度电容读出电路的单芯片集成研究 总被引：1，自引：0，他引：1
MEMS电容式传感器的迅速发展为后续集成化读出电路的设计提出了巨大挑战.系统地分析了制约微传感器高精度电容读出电路设计的主要因素,回顾了目前主要的几种读出电路结构,阐述了这些电路的基本原理,并对影响电路分辨率的主要设计参数进行了分析和对比,最后探讨了电容式读出电路设计的发展趋势. 相似文献
15.
科研院所是我们国家建设创新型国家进程中的一支战略科技力量,提高科研院所知识与技术创新的质量与效率非常重要。该文在对科研院所设计过程的步骤、规律进行系统化分析的基础上,引入了田口设计技术和方法,重点是三次设计,将其在产品生命周期不同阶段的运用成果反映出来,表明先进设计技术和方法是挖掘科研院所现有的技术潜力,提高设计质量的... 相似文献
16.
In this paper we consider the utilization of multiple transmitterand receiver antennas for space-time diversity. The optimalSNR scheme, which also provides the best diversity, is outlined.This scheme however involves a reduction in the data rate. Coding schemes are then presentedwhich not only achieve the optimal SNR but also mitigate the reductionof data rate. The proposed schemes are based on the theory of Orthogonal Designsand Amicable Orthogonal Designs. 相似文献
17.
In this paper,we focus on antenna array design for mobile phone with finite volume and propose a novel antenna element structure by capacitive feeding and capacitive loading method based on the planar ... 相似文献
18.
19.
The capacitance versus DC-voltage formula from electron trapping at dopant impurity centers is derived for MOS capacitors by the charge-storage method. Fermi–Dirac distribution and impurity deionization are included in the DC-voltage scale. The low-frequency and high-frequency capacitances, and their differences and derivatives, are computed in the presence of an unlimited source of minority and majority carriers. The results show that their difference and their DC-voltage derivatives, are large and readily measurable, hence suitable as a method for characterizing the electronic trapping parameters at dopant impurity centers and for a number of lower power signal processing and device technology monitoring applications. 相似文献
20.
The capacitance versus DC-voltage formula from electron trapping at dopant impurity centers is derived for MOS capacitors by the charge-storage method.Fermi-Dirac distribution and impurity deionization are included in the DC-voltage scale.The low-frequency and high-frequency capacitances,and their differences and derivatives,are computed in the presence of an unlimited source of minority and majority carriers.The results show that their difference and their DC-voltage derivatives,are large and readily measurable,hence suitable as a method for characterizing the electronic trapping parameters at dopant impurity centers and for a number of lower power signal processing and device technology monitoring applications. 相似文献