Article
Nanoscience & Nanotechnology
Zi Li, Huifeng Yao, Wenxuan Wang, Chang Eun Song, Du Hyeon Ryu, Yang Xiao, Jingwen Wang, Lijiao Ma, Tao Zhang, Junzhen Ren, Cunbin An, Won Suk Shin, Jianhui Hou
Summary: Designing efficient non-fused ring electron acceptors is crucial for reducing the material cost of organic photovoltaic cells. In this study, two non-fused electron acceptors based on bithieno[3,2-b]thiophene units were designed, and the impact of steric hindrance on molecular planarity was investigated. The results showed that enhanced steric hindrance improved the planarity of the molecules, leading to higher optical absorption and charge transport properties. This research highlights the importance of controlling molecular planarity through modulation of steric hindrance for achieving excellent photovoltaic performance of low-cost non-fused electron acceptors.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Xiaoxiao Li, Xueting Li, Tingting Xia, Wei Chen, Kenneth J. Shea, Xihua Lu
Summary: It is discovered that introducing hydrophobic N-tert-butylacrylamide (TBA) with large sterically hindering side groups can slow down the dehydration of hydrophobic alkyl groups in PNIPAm-based nanogels, resulting in thermally induced sol-gel transition above the phase transition temperature (T-p). Furthermore, the introduction of N-acrylamido-L-phenylalanine (APhe) monomer with a strongly water-absorbing carboxyl group and larger steric hindrance can self-assemble PNIPAm/TBA/APhe terpolymer nanogels into colorful colloidal crystals that undergo sol-gel transition above T-p.
MATERIALS HORIZONS
(2023)
Article
Chemistry, Multidisciplinary
Stefania Moro, Nicholas Siemons, Oscar Drury, Daniel A. Warr, Thomas A. Moriarty, Luis M. A. Perdigao, Drew Pearce, Maximilian Moser, Rawad K. . Hallani, Joseph Parker, Iain McCulloch, Jarvist M. Frost, Jenny Nelson, Giovanni Costantini
Summary: Conjugated polymers with glycol-based chains have promising applications in bioelectronics and thermoelectrics. In this study, we determined the microstructure of these polymers with submonomer resolution and found that the side chains play a crucial role in polymer assembly. The conformation of the side chains is influenced by their free analogues, rather than the backbone torsional potential energy. These findings can be extended to other conjugated polymers for microstructure characterization.
Article
Polymer Science
Haoyu Zhao, Jordan J. Shanahan, Stephanie Samson, Zhaofan Li, Guorong Ma, Nathaniel Prine, Luke Galuska, Yunfei Wang, Wenjie Xia, Wei You, Xiaodan Gu
Summary: The morphological stability of an organic photovoltaic device can be improved by cleaving the side chains, which raises the glass transition temperature (Tg) of the conjugated polymers. Experimental results showed that isothermal annealing with controlled side chain cleavage increased the Tg and maintained the crystalline structure. Coarse grain molecular dynamics simulations supported these findings.
MACROMOLECULAR RAPID COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Xudong Jiang, Wenyue Xue, Wenbin Lai, Dongdong Xia, Qiaomei Chen, Wei Ma, Weiwei Li
Summary: This study systematically investigated the effects of alkyl side units of double-cable conjugated polymers on the photovoltaic performance of single-component organic solar cells. It was found that polymers with longer alkyl side units exhibited lower charge carrier mobilities and efficiencies.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Polymer Science
Min-Kyoung Kim, Gyung-Tak Kim, Taemin Kim, Moon-Gyu Kim, Felix Sunjoo Kim, Taeshik Earmme, Ye-Jin Hwang
Summary: Two poly(naphthalene diimide)s (PNDIs) were developed using different conjugated side chains, with P(NDI-BBT) having higher absorption coefficient and narrower optical energy band gap compared to P(NDI-BT), and also lower lowest unoccupied molecular orbital energy levels. Interestingly, lower crystallinity was observed in P(NDI-BBT) compared to P(NDI-BT).
EUROPEAN POLYMER JOURNAL
(2021)
Article
Chemistry, Applied
Junfeng Tong, Zheyu Li, Yubo Huang, Yan Wang, Lichun Zhang, Lili An, Pengzhi Guo, Chunyan Yang, Jianfeng Li, Yangjun Xia
Summary: The alkoxy side chain containing the electronegative oxygen plays a critical role in tuning the optoelectronic and photovoltaic properties. However, incorporating the alkoxy side chain into the perylene diimide (PDI) building block has been rarely studied. In this study, three polymeric acceptors with different side chains were prepared to investigate the impact of bonding the alkoxy side chain on various properties. The results showed that introducing the alkoxy side chain resulted in improved molecular planarity, absorption properties, charge mobility, and device efficiency in all-polymer solar cells.
Article
Engineering, Electrical & Electronic
Sheik Haseena, Mahesh Kumar Ravva
Summary: Experimental studies have shown that the length and position of alkoxy side-chains significantly influence the power conversion efficiencies of solar cell devices. A detailed analysis using quantum chemical methods has been conducted to explore how the length of these side-chains impact the molecular packing and electronic and optical properties, providing insights into the reasons behind better device efficiencies with certain alkoxy side-chains.
JOURNAL OF ELECTRONIC MATERIALS
(2021)
Article
Polymer Science
Fengsheng Zhao, Ye Yuan, Yafei Ding, Yunfei Wang, Xiaohong Wang, Guobing Zhang, Xiaodan Gu, Longzhen Qiu
Summary: Compared to PTDPPTT-Si-3, PTDPPTT-Si-5 and PTDPPTT-Si-7 have longer siloxane-terminal groups, allowing for better solution processability and higher mobilities.
Article
Chemistry, Multidisciplinary
Lingwei Xue, Chaoyi Yan, Jia Yao, Meifang Zhang, Qingbin Li, Qi Chen, Ze Zhang, Haiqiao Wang, Zitong Liu, Guo Yao, Chunfeng Zhang, Jiangang Liu, Zhi-Guo Zhang
Summary: In the field of organic solar cells, conducting shoulder side-chain engineering on Y-series non-fullerene acceptors has attracted great interest for achieving high power conversion efficiencies (PCEs). In this study, a method for post-attaching shoulder side chains on Y-series NFAs is reported, which offers advantages of using low-cost raw materials and convenient attachment of conjugated side chains. The results demonstrate that this post-side-chain engineering method is a convenient and low-cost approach to construct high-performance NFAs.
CELL REPORTS PHYSICAL SCIENCE
(2023)
Article
Chemistry, Physical
Pablo Durand, Huiyan Zeng, Till Biskup, Vishnu Vijayakumar, Viktoriia Untilova, Celine Kiefer, Benoit Heinrich, Laurent Herrmann, Martin Brinkmann, Nicolas Leclerc
Summary: Combining side chain engineering and controlled alignment of PBTTT can produce oriented thin films with improved thermoelectric performance when doped sequentially with F(6)TCNNQ. The substitution of linear alkyl side-chains with slightly polar n-C7OC4 leads to enhanced structural order and thermo-mechanical properties. The combination of improved alignment and random orientation of intercalated F(6)TCNNQ dopants helps reach a very high charge conductivity and a record power factor in the polymer chain direction.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Haobo Yuan, Zequn Zhang, Tonghui Guo, Luting Yu, Zhiqiang Deng, Rui Zhao, Jing Zhang, Yuejin Zhu
Summary: This study revealed the steric effect of Lewis-acid base additives by applying two amino acids, circular proline and linear glycine. Proline showed better coordination effect in perovskite solar cells, promoting crystal growth and trap states passivation. The research highlights the importance of considering steric effect when choosing and designing Lewis adducts in perovskite solar cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Jongbok Lee, Shi Li, Xiaozhou Ji, Sai Che, Yirui Cao, Daniel P. Tabor, Lei Fang
Summary: This study investigates the factors affecting the doping mechanism of organic semiconductors using neutral dopants. The results show that the extended, rigid, and coplanar pi-faces play a crucial role in the doping interaction. This work provides principles for the molecular design of organic semiconductors and dopants.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Polymer Science
Zhi-Chao Yan, Yanan Li, Zhenfeng Guo, Akira Shinohara, Takashi Nakanishi, Guangming Chen, Chengjun Pan, Florian J. Stadler
Summary: This study examines the linear viscoelasticity of viscoelastic conjugated polymers based on dialkyl-fluorene and dialkoxybenzene over a wide temperature range. Three dynamic transition temperatures are identified and attributed to different parts of the polymer structure. The findings suggest that the properties of different components of the polymer exhibit distinct behaviors under varying temperature conditions.
Article
Polymer Science
Gang Huang, Ning Wu, Xiaohong Wang, Guobing Zhang, Longzhen Qiu
Summary: Molecular weight is a key factor influencing the properties of conjugated polymers. It has been found that below the critical molecular weight, conjugated polymers exhibit high crystallinity and low ductility; when the molecular weight approaches the critical value, the crystallinity decreases and ductility increases; when the molecular weight is much higher than the critical value, the polymer films show significant ductility.
MACROMOLECULAR RAPID COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Jun Hu, Zhenzhou Nie, Meng Wang, Zhiyang Liu, Shuai Huang, Hong Yang
Summary: Jumping is an important motion for animals to escape predators and adapt to the environment. Inspired by springtails, researchers have developed a light-driven soft jumping robot with impressive jumping capabilities. By changing the size and crease angle of the ribbon actuators, the robot can control its jump height, distance, and direction. These robots can efficiently jump over obstacles and continue jumping in complex environments, showing promising potential for future soft robots.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Engineering, Electrical & Electronic
Duo Xu, Shaomeng Wang, Chang Lu, Tenglong He, Zhanliang Wang, Zhigang Lu, Huarong Gong, Zhaoyun Duan, Yubin Gong
Summary: This article presents a Ka-band prototype traveling wave tube (TWT) with a single-stage gain of more than 35 dB, utilizing a modified angular log-periodic folded waveguide (MALP-FW) slow wave structure (SWS). The experimental results show that the MALP-FW SWS successfully suppresses oscillations and the output signal spectrum is noise-free. These findings confirm the potential application of MALP-FW SWS in terahertz TWTs.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Chuang Wang, Zidong Wang, Weibo Liu, Yuxuan Shen, Hongli Dong
Summary: This article proposes a two-stage deep offline-to-online transfer learning framework (DOTLF) for long-distance pipeline leakage detection (PLD). At the offline training stage, a feature transfer-based long short-term memory network with regularization information (TL-LSTM-Ri) is developed to extract domain-invariant features and early fault features. At the online detection stage, the trained TL-LSTM-Ri is used for motion prediction to monitor the pipeline's operating condition in real time. The DOTLF is successfully applied to real-time PLD on long-distance oil-gas pipeline data, and experimental results demonstrate its effectiveness.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Chemistry, Multidisciplinary
Meng Wang, Tao Hu, Hari Krishna Bisoyi, Zhen Yu, Li Liu, Ying Song, Jianfeng Yang, Hong Yang, Quan Li
Summary: This study presents a novel thermal/photo/magnetorheological water-based magnetic fluid with excellent suspension stability and controllable rheological properties. The fluid is composed of magnetic nanoparticles and a water-based carrier, and it exhibits reversible changes between low-viscosity flow state and 3D gel structure. Additionally, the rheological changes can be controlled using near infrared light and alternating magnetic field, making the fluid applicable in various fields.
Article
Automation & Control Systems
Kaiqun Zhu, Zidong Wang, Qing-Long Han, Guoliang Wei
Summary: This article investigates the distributed set-membership fusion filtering problem for nonlinear 2-D shift-varying systems subject to unknown-but-bounded noises over sensor networks. It introduces a logarithmic-type encoding-decoding mechanism for each sensor node to enhance transmission security and relieve communication burden. A distributed set-membership filter is designed to determine the local ellipsoidal set that contains the system state. A new ellipsoid-based fusion rule is developed to form the fused ellipsoidal set with a globally smaller volume. Sufficient conditions are derived for the existence of the desired distributed set-membership filters and fusion weights.
IEEE TRANSACTIONS ON CYBERNETICS
(2023)
Article
Automation & Control Systems
Wei Chen, Zidong Wang, Derui Ding, Gheorghita Ghinea, Hongjian Liu
Summary: This article investigates the distributed formation-containment (FC) control problem for a class of discrete-time multiagent systems (DT-MASs) under the event-triggered communication mechanism. A novel dynamic event-triggered (DET) mechanism is developed to save communication cost and improve resource utilization. Based on available relative outputs, a distributed FC control scheme under the DET mechanism is proposed for all leaders and followers. The goal is to design an FC controller such that all leaders achieve formation shape and all followers converge into a convex hull. The considered DT-MASs are decoupled into a diagonal form using the Laplacian matrix property and inequality technique, and two sufficient conditions are established to ensure the desired FC performance. The FC controller parameters are obtained based on the solutions to two matrix inequalities depending on the maximum and minimum nonzero eigenvalues of the Laplacian matrix. An illustrative example is provided to verify the effectiveness of the developed control scheme.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Zugen Guo, Ruifeng Zhang, Han Lai, Feng Lan, Zhanliang Wang, Zhigang Lu, Zhaoyun Duan, Yubin Gong, Huarong Gong
Summary: In this article, a design scheme of an electron-optical system (EOS) for terahertz vacuum electron amplifiers is presented. The performance characteristics are studied by simulation, and the feasibility is verified by transmission experiment. The design includes an electron gun with an isolated beam focus electrode (BFE) based on the Pierce design method, and a periodic permanent magnet (PPM) system for focusing beam transportation.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Automation & Control Systems
Yang Liu, Zidong Wang, Cunjia Liu, Matthew Coombes, Wen-Hua Chen
Summary: This article addresses the particle filtering problem for nonlinear/non-Gaussian systems with quantized measurements and multiple degrading sensors. It proposes a degradation variable described by the Wiener process to model sensor degradation commonly encountered in engineering practice. An augmented system is constructed to aggregate the original system state and the degradation variables. A novel particle filtering algorithm is developed considering the sensor degradation and quantization errors, where the parameters of degradation processes and quantization functions are exploited to obtain modified importance weights. The effectiveness of the proposed method is demonstrated through a target tracking example with bearing measurements.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
Article
Automation & Control Systems
Bogang Qu, Zidong Wang, Bo Shen, Hongli Dong
Summary: This article studies the problem of state estimation in a class of renewable-electricity-generation-based microgrids with measurement outliers. A state-space system model is proposed for microgrids using the physical laws of power systems, without considering prior knowledge of the measurement outliers. To enhance insensitivity against measurement outliers, an outlier-resistant SE algorithm is developed with two distinct features: adopting a saturation function to constrain the innovation term in the state estimator and minimizing the estimation error covariance by selecting proper gain parameters. Simulation studies on a benchmark islanded microgrid with two renewable-electricity-generation units are conducted to illustrate the validity of the developed algorithm.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
Article
Engineering, Electrical & Electronic
Junwan Zhu, Jingrui Duan, Zhigang Lu, Zhanliang Wang, Huarong Gong, Yubin Gong
Summary: To improve the performance of sine waveguide traveling wave tubes, a new elliptical beam-tunnel sine waveguide slow wave structure (EBTSW-SWS) is proposed. Compared to the traditional SW-SWS, the EBTSW-SWS has a wider passband and higher interaction impedance. Particle-in-cell simulation results show that the EBTSW-TWT can provide more than 70 W of output power with a maximum efficiency of 4.85% in the frequency range of 200-260 GHz.
JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS
(2023)
Review
Materials Science, Multidisciplinary
Meng Wang, Xiang Huang, Hong Yang
Summary: Crosslinked liquid crystal polymers (CLCPs) are smart polymer materials with excellent two-way shape memory behavior under external stimuli. Light, with its advantages of instantaneity, high accuracy, remote controllability, and pollution-free nature, has been widely used to control CLCPs. Recently, there has been scientific attention towards designing photoresponsive CLCPs based on the photothermal effect. Photothermal-responsive CLCPs can achieve reversible macroscopic deformation using photothermal materials to locally heat the CLCP matrix. This review discusses photothermal-responsive CLCPs under different light wavelengths and their application fields, as well as the current challenges and future development.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2023)
Article
Chemistry, Analytical
Zechuan Wang, Junwan Zhu, Zhigang Lu, Jingrui Duan, Haifeng Chen, Shaomeng Wang, Zhanliang Wang, Huarong Gong, Yubin Gong
Summary: A novel staggered double-segmented grating slow-wave structure (SDSG-SWS) is proposed in this paper for wide-band high-power submillimeter wave traveling-wave tubes (TWTs). The SDSG-SWS combines the advantages of sine waveguide (SW) SWS and staggered double-grating (SDG) SWS, resulting in wide operating band, high interaction impedance, low ohmic loss, low reflection, and ease of fabrication. Analysis of high-frequency characteristics shows that the SDSG-SWS has higher interaction impedance compared to SW-SWS, while the ohmic loss remains similar. The beam-wave interaction calculation results demonstrate that the TWT using SDSG-SWS can achieve an output power above 16.4 W in the frequency range of 316 GHz-405 GHz, with a maximum power of 32.8 W at 340 GHz, and a maximum electron efficiency of 2.84% at an operating voltage of 19.2 kV and current of 60 mA.
Article
Chemistry, Analytical
Yang Dong, Shaomeng Wang, Jingyu Guo, Zhanliang Wang, Huarong Gong, Zhigang Lu, Zhaoyun Duan, Yubin Gong
Summary: This paper proposes an angular radial extended interaction amplifier (AREIA) that consists of a pair of angular extended interaction cavities, which show potential in improving the beam-wave interaction capability of W-band extended interaction klystrons (EIKs). Compared to conventional radial cavities, the angular cavities greatly reduce ohmic loss area and increase characteristic impedance. Particle-in-cell (PIC) results demonstrate the superiority of the proposed design in terms of output power and beam-wave interaction capacity compared to conventional EIAs under certain conditions.
Article
Chemistry, Multidisciplinary
Xiaoping Jiang, Yurong Liu, Tianning Xiu
Summary: X-ray diffraction technology (XRD) is commonly used for mineral separation, and peak identification and comparison are crucial steps. This article proposes an improved symmetric zero-area conversion method (ISZAC) combining data fusion and passive anti-counterfeiting. By introducing a comparison method and flat peak screening, and designing a function group to convert spectral data, the peak address determination is obtained through result fusion. Simulation and experimental results demonstrate that the improved method has higher accuracy and applicability, and can be easily expanded and adjusted for improved recognition efficiency based on spectral data characteristics.
APPLIED SCIENCES-BASEL
(2023)
Article
Automation & Control Systems
Ye Yuan, Xin Luo, Mingsheng Shang, Zidong Wang
Summary: This study proposes a QoS estimator based on Kalman filter and latent factor analysis for accurate representation of temporally dynamic QoS data. Empirical studies on large-scale real-world datasets demonstrate that the proposed model outperforms existing methods in estimation accuracy for dynamic QoS data.
IEEE TRANSACTIONS ON CYBERNETICS
(2023)
