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961.
Yuanyuan Meng Jiasen Zhang Chang Liu Kanghui Zheng Lisha Xie Shixiao Bu Bin Han Ruikun Cao Xu Yin Cuirong Liu Ziyi Ge 《Advanced functional materials》2023,33(3):2210600
Formamidinium lead triiodide (FAPbI3) has been demonstrated as the most efficient perovskite system to date, due to its excellent thermal stability and an ideal bandgap approaching the Shockley-Queisser limit. Whereas, there are intrinsic quantum confinement effects in FAPbI3, which lead to unwanted non-radiative recombination. Additionally, the black α-phase of FAPbI3 is unstable under room temperature due to the significant residual tensile stress in the film. To simultaneously address the above issues, a thermally-activated delayed fluorescence polymer P1 is designed in the study to modify the FAPbI3 film. Owing to the spectral overlap between the photoluminescence of P1 and absorption of the above-bandgap quantum wells of FAPbI3, the Förster energy transfer occurs at the P1/FAPbI3 interface, which further triggers the Dexter energy transfer within FAPbI3. The exciton “recycling” can thus be realized, which reduces the non-radiative recombination losses in perovskite solar cells (PSCs). Moreover, P1 is found to introduce compressive stress into FAPbI3, which relieves the tensile stress in perovskite. Consequently, the PSCs with P1 treatment achieve an outstanding power conversion efficiency (PCE) of 23.51%. Moreover, with the alleviation of stress in the perovskite film, flexible PSCs (f-PSCs) also deliver a high PCE of 21.40%. 相似文献
962.
Youyu Duan Yang Wang Weixuan Zhang Jiangwei Zhang Chaogang Ban Danmei Yu Kai Zhou Jinjing Tang Xu Zhang Xiaodong Han Liyong Gan Xiaoping Tao Xiaoyuan Zhou 《Advanced functional materials》2023,33(28):2301729
Photocatalytic conversion of CO2 into fuels using pure water as the proton source is of immense potential in simultaneously addressing the climate-change crisis and realizing a carbon-neutral economy. Single-atom photocatalysts with tunable local atomic configurations and unique electronic properties have exhibited outstanding catalytic performance in the past decade. However, given their single-site features they are usually only amenable to activations involving single molecules. For CO2 photoreduction entailing complex activation and dissociation process, designing multiple active sites on a photocatalyst for both CO2 reduction and H2O dissociation simultaneously is still a daunting challenge. Herein, it is precisely construct Cu single-atom centers and two-coordinated N vacancies as dual active sites on CN (Cu1/N2CV-CN). Experimental and theoretical results show that Cu single-atom centers promote CO2 chemisorption and activation via accumulating photogenerated electrons, and the N2CV sites enhance the dissociation of H2O, thereby facilitating the conversion from COO* to COOH*. Benefiting from the dual-functional sites, the Cu1/N2CV-CN exhibits a high selectivity (98.50%) and decent CO production rate of 11.12 µmol g−1 h−1. An ingenious atomic-level design provides a platform for precisely integrating the modified catalyst with the deterministic identification of the electronic property during CO2 photoreduction process. 相似文献
963.
Hanfei Li Fei Han Lulu Wang Laixin Huang Oluwarotimi Williams Samuel Hang Zhao Ruijie Xie Ping Wang Qiong Tian Qingsong Li Yang Zhao Mei Yu Jing Sun Ruofan Yang Xiaomeng Zhou Fei Li Guanglin Li Yi Lu Peizhi Guo Zhiyuan Liu 《Advanced functional materials》2023,33(29):2300859
Stretchable ultra-narrow (e.g., 10 µm in width) microelectrodes are crucial for the electrophysiological monitoring of single cells providing the fundamental understanding to the working mechanism of neuro network or other electrically functional cells. Current fabrication strategies either focus on the preparation of normal stretchable electrodes with hundreds of micrometers or millimeters in width by using inorganic conductive materials or develop conductive organic polymer gel for ultra-narrow electrodes which suffer from low stretchability and instability for long-term implantation, therefore, it is still highly desirable to explore bio-interfacial ultra-narrow stretchable inorganic electrodes. Herein, a hybrid strategy is reported to prepare ultra-narrow multi-channel stretchable microelectrodes without using photolithography or laser-assisting etching. A 10 µm × 10 µm monitoring window is fabricated with enhanced interfacial impedance by the special rough surface. The stretchability achieves to 120% for this 10 µm-width stretchable electrode. Supported by these superior properties, it is demonstrated that the stretchable microelectrodes can detect electrophysiological signals of single cells in vitro and collect electrophysiological signals more precisely in vivo. The reported strategy will open up the accessible preparation of the fine-size stretchable microelectrode. It will significantly improve the resolution of monitoring and stimulation of inorganic stretchable electrodes. 相似文献
964.
Guohua Zhang Jingrun Qin Yue Zhang Guodong Gong Zi-Yu Xiong Xiangyu Ma Ziyu Lv Ye Zhou Su-Ting Han 《Advanced functional materials》2023,33(42):2302929
The booming development of artificial intelligence (AI) requires faster physical processing units as well as more efficient algorithms. Recently, reservoir computing (RC) has emerged as an alternative brain-inspired framework for fast learning with low training cost, since only the weights associated with the output layers should be trained. Physical RC becomes one of the leading paradigms for computation using high-dimensional, nonlinear, dynamic substrates. Among them, memristor appears to be a simple, adaptable, and efficient framework for constructing physical RC since they exhibit nonlinear features and memory behavior, while memristor-implemented artificial neural networks display increasing popularity towards neuromorphic computing. In this review, the memristor-implemented RC systems from the following aspects: architectures, materials, and applications are summarized. It starts with an introduction to the RC structures that can be simulated with memristor blocks. Specific interest then focuses on the dynamic memory behaviors of memristors based on various material systems, optimizing the understanding of the relationship between the relaxation behaviors and materials, which provides guidance and references for building RC systems coped with on-demand application scenarios. Furthermore, recent advances in the application of memristor-based physical RC systems are surveyed. In the end, the further prospects of memristor-implemented RC system in a material view are envisaged. 相似文献
965.
Yixing Li Linlin Yang Yijun Liao Rongzhi Zhao Lianze Ji Rui Su Dake Xu Fuhui Wang 《Advanced functional materials》2023,33(35):2302712
Antibacterial elements and non-contact heating abilities have been proven effective for antibacterial and antibiofilm activities, but it remains a challenge to integrate both within one material. Herein, assisted by the high-entropy effect, FeNiTiCrMnCux high-entropy alloy nanoparticles (HEA-NPs) with excellent photothermal heating properties for boosting antibacterial and antibiofilm performances are synthesized. Benefitting from the synergetic effect of copper ions released and thermal damage by the HEA-NPs, more reactive oxygen species (ROS) are generated, leading to the rupture of the cell membranes and the eradication of the biofilms. As a result, the antibiofilm efficiency (400 µg mL−1) of the mostly optimized FeNiTiCrMnCu1.0 HEA-NPs in the marine nutrient medium, which is the worst-case scenario for the antimicrobial material, can be improved from 81% to 97.4% under 30 min solar irradiation (1 sun). The present study demonstrates a new strategy for effectively treating marine microorganisms that cause biofouling and microbial corrosion using HEA-NPs with photothermal heating characteristics as an antibacterial auxiliary. 相似文献
966.
超声造影(Contrast-enhanced ultrasound, CEUS)通过外周静脉注入超声造影剂,显著增强来自肿瘤微血管的血流信号,便于临床医生以实时、动态的方式评估肿瘤血管生成、周边浸润等,广泛应用于多器官病变诊断、预后评估和治疗方案规划等方面。近年来,以深度学习为代表的机器学习方法快速发展,为动态超声造影智能分析带来新的机遇。深度学习方法很大程度上拓宽了超声造影临床应用范围,提高了其诊疗效能。但与常规超声影像类似,超声造影仍然存在斑点噪声、呼吸运动干扰和标准化程度低等问题,使得动态灌注时间、空间信息挖掘面临挑战。本文系统性回顾了近年来超声造影智能分析相关工作,涵盖良恶性鉴别、恶性分级、疗效预测和诊疗方案选择等方面应用,总结了当前影像组学及深度学习方法在超声造影分析领域的最新进展,并指出当前研究的局限性和未来发展方向。 相似文献
967.
Zhang Man Zhou Yong Liu Bing Zhao Jiaqi Yao Rui Shao Zhiwen Zhu Hancheng Chen Hao 《Pattern Analysis & Applications》2023,26(2):669-677
Pattern Analysis and Applications - The designed method aims to perform image classification tasks efficiently and accurately. Different from the traditional CNN-based image classification methods,... 相似文献
968.
无刷直流永磁电机因节能高效、便于使用等优势而受到广泛关注。然而,该类电机通常因空载感应电动势波形不理想而具有转矩脉动较大等问题。以24槽4极无刷直流永磁电机为例,基于气隙磁场调制理论分析了转子永磁型无刷直流电机的空载感应电动势等电磁特性,以磁场调制原理中的永磁初始磁动势源为切入点,探讨影响电机空载感应电动势波形系数的因素并揭示感应电动势形成的内在机理。首先,针对24槽4极传统转子永磁无刷直流电机的运行原理和空载气隙磁场进行分析,并根据得出的结论采取永磁体谐波削极的方式优化电机空载感应电动势波形系数,最后通过仿真验证了理论分析和优化方案的合理性。 相似文献
969.
对全超导托卡马克核聚变实验装置东方超环(EAST)运行放电期间发生的杂质破裂进行预测对未来的聚变装置的长脉冲稳态放电有重要意义. 根据杂质破裂的物理特性筛选出的2018年的334炮杂质破裂炮数据以及2021年的1628 炮非破裂炮作为训练炮, 再由等离子体平衡、密度、电流以及辐射等8种诊断信号组成的训练样本以LightGBM算法训练出杂质破裂预测模型. 实验结果表明LightGBM算法模型可以对杂质破裂进行准确预测(成功预测率96.29%), 非破裂炮的误判率6.87%. 研究结果证明利用LightGBM进行EAST等离子体杂质破裂预警是可行的方案. 相似文献
970.
针对DeepLabV3+在特征提取阶段忽略了不同尺度特征重要程度出现的部分细节信息损失导致图像分割不细致,提出一种融合双分支特征提取和注意力机制的改进算法. ResNet101骨干网络初步提取出的特征图作为注意力机制的输入特征,解决了网络退化及梯度消失的问题,也能够捕获到被DeepLabV3+忽略的图像细节信息;设计双分支特征提取机制扩大特征提取能力,细化图像边缘信息以优化网络对不同尺度特征关注不均的问题;同时,联合采用交叉熵损失和类别不平衡函数两种损失函数作为损失函数,通过聚焦于前景样本降低背景的影响,提高算法分割精度.实验结果表明,改进算法在PASCAL VOC 2012和CityScapes数据集上的平均交并比(MIoU)值分别达到了79.92%和68.59%,与经典算法和基于DeepLabV3+改进的算法相比,特征提取的准确性有所提高,分割效果更优. 相似文献