Mutawara Mahmood Baig, Suhail Ayoub Khan, Hamza Ahmad, Jin Liang, Guoyin Zhu, Huan Pang, Yizhou Zhang
Advances in hydrogel technology have paved the way for novel and valuable capabilities that are being applied to a diverse spectrum of energy storage applications. Hydrogels, originally renowned for their biomedical applications, are now finding translation into the energy storage domain. These versatile materials exhibit promising potential for various energy-related applications, including but not limited to acting as highly flexible electrolytes, facilitating the development of flexible supercapacitors, and contributing to advancements in energy conversion devices. The tunable properties of hydrogels, their high ion accessibility, and desirable mechanical characteristics position them as promising candidates for enhancing the performance and efficiency of energy storage systems. In this review, we emphasize the integration of hydrogels into flexible micro-supercapacitors through 3D printing technology, unraveling the charge transport mechanisms inherent in hydrogels. We discuss methods for developing hydrogels with enhanced physicochemical properties, such as improved mechanical strength, flexibility, and charge transport, offering new prospects for next-generation energy storage devices. With a deeper understanding of gelation chemistry, we showcase significant progress in fabricating stimuli-responsive, self-healing, and highly stretchable hydrogels. Furthermore, we present compelling examples highlighting the versatility of hydrogels, including tailorable architectures, conductive nanostructures, 3D frameworks, and multifunctionalities. The application of innovative 3D printing techniques in hydrogel design is poised to yield materials with immense potential in the realm of energy storage.
{"title":"3D printing of hydrogels for flexible micro-supercapacitors","authors":"Mutawara Mahmood Baig, Suhail Ayoub Khan, Hamza Ahmad, Jin Liang, Guoyin Zhu, Huan Pang, Yizhou Zhang","doi":"10.1002/flm2.14","DOIUrl":"https://doi.org/10.1002/flm2.14","url":null,"abstract":"<p>Advances in hydrogel technology have paved the way for novel and valuable capabilities that are being applied to a diverse spectrum of energy storage applications. Hydrogels, originally renowned for their biomedical applications, are now finding translation into the energy storage domain. These versatile materials exhibit promising potential for various energy-related applications, including but not limited to acting as highly flexible electrolytes, facilitating the development of flexible supercapacitors, and contributing to advancements in energy conversion devices. The tunable properties of hydrogels, their high ion accessibility, and desirable mechanical characteristics position them as promising candidates for enhancing the performance and efficiency of energy storage systems. In this review, we emphasize the integration of hydrogels into flexible micro-supercapacitors through 3D printing technology, unraveling the charge transport mechanisms inherent in hydrogels. We discuss methods for developing hydrogels with enhanced physicochemical properties, such as improved mechanical strength, flexibility, and charge transport, offering new prospects for next-generation energy storage devices. With a deeper understanding of gelation chemistry, we showcase significant progress in fabricating stimuli-responsive, self-healing, and highly stretchable hydrogels. Furthermore, we present compelling examples highlighting the versatility of hydrogels, including tailorable architectures, conductive nanostructures, 3D frameworks, and multifunctionalities. The application of innovative 3D printing techniques in hydrogel design is poised to yield materials with immense potential in the realm of energy storage.</p>","PeriodicalId":100533,"journal":{"name":"FlexMat","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/flm2.14","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140648129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Cu-based halide semiconductor CuGaI4 was prepared by a high-temperature melting method. Optoelectronic characterization and density functional theory calculations of CuGaI4 reveal a direct bandgap of 2.9 eV. The corresponding UV photodetector (PD) based on CuGaI4 demonstrates excellent UV response and rapid response time. In addition, a flexible PD based on CuGaI4 is prepared, which also displays excellent photoresponse characteristics and mechanical stability. This work provides a systematic study of this novel Cu-based halide semiconductor and demonstrates the great potential of CuGaI4 for future UV optoelectronic devices.
{"title":"Flexible UV photodetector based on copper tetraiodogallate (CuGaI4) film","authors":"Haoyu Chen, Bingxu Liu, Jiupeng Cao, Lian Ji, Jiankai Xie, Yuting Shu, Jingjin Dong, Aifei Wang, Fangfang Wang, Feng Yan, Tianshi Qin","doi":"10.1002/flm2.13","DOIUrl":"https://doi.org/10.1002/flm2.13","url":null,"abstract":"<p>The Cu-based halide semiconductor CuGaI<sub>4</sub> was prepared by a high-temperature melting method. Optoelectronic characterization and density functional theory calculations of CuGaI<sub>4</sub> reveal a direct bandgap of 2.9 eV. The corresponding UV photodetector (PD) based on CuGaI<sub>4</sub> demonstrates excellent UV response and rapid response time. In addition, a flexible PD based on CuGaI<sub>4</sub> is prepared, which also displays excellent photoresponse characteristics and mechanical stability. This work provides a systematic study of this novel Cu-based halide semiconductor and demonstrates the great potential of CuGaI<sub>4</sub> for future UV optoelectronic devices.</p>","PeriodicalId":100533,"journal":{"name":"FlexMat","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/flm2.13","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140643464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Triboelectric nanogenerators (TENGs) have recently gained attention as a compelling platform technology for building wearable bioelectronics. Aside from being self-powered, TENGs are lightweight, low in cost, rich in material choice, comfortable to wear, and increasingly versatile with advances in sensitivity and efficiency. Due to these features, TENGs have become appealing in biomedical sensing applications, especially for human respiration monitoring. A wealth of information can be collected by breath-induced electrical signals, which are crucial in the analysis of a patient's respiratory condition and the early detection of harmful respiratory-linked diseases. TENGs have thus been used to continuously collect important respiratory data, from the breathing patterns, flow rate, and intensity of an individual's respiratory cycle to the chemicals that may be present in their breath. This review paper provides an overview of recent developments in TENG-based wearable respiratory monitoring as well as future opportunities and challenges for respiratory healthcare.
三电纳米发电机(TENGs)作为构建可穿戴生物电子学的一项引人注目的平台技术,近来备受关注。除了自供电外,TENG 重量轻、成本低、材料选择丰富、佩戴舒适,而且随着灵敏度和效率的提高,其用途也越来越广泛。由于这些特点,TENGs 在生物医学传感应用中,尤其是在人体呼吸监测方面具有吸引力。呼吸引起的电信号可以收集大量信息,这些信息对于分析病人的呼吸状况和早期发现与呼吸有关的有害疾病至关重要。因此,TENGs 已被用于持续收集重要的呼吸数据,包括呼吸模式、流速、个人呼吸周期的强度以及呼吸中可能存在的化学物质。本综述文件概述了基于 TENG 的可穿戴呼吸监测技术的最新发展,以及呼吸保健领域未来的机遇和挑战。
{"title":"Advances in triboelectric nanogenerators for self-powered wearable respiratory monitoring","authors":"William Kwak, Junyi Yin, Shaolei Wang, Jun Chen","doi":"10.1002/flm2.10","DOIUrl":"https://doi.org/10.1002/flm2.10","url":null,"abstract":"<p>Triboelectric nanogenerators (TENGs) have recently gained attention as a compelling platform technology for building wearable bioelectronics. Aside from being self-powered, TENGs are lightweight, low in cost, rich in material choice, comfortable to wear, and increasingly versatile with advances in sensitivity and efficiency. Due to these features, TENGs have become appealing in biomedical sensing applications, especially for human respiration monitoring. A wealth of information can be collected by breath-induced electrical signals, which are crucial in the analysis of a patient's respiratory condition and the early detection of harmful respiratory-linked diseases. TENGs have thus been used to continuously collect important respiratory data, from the breathing patterns, flow rate, and intensity of an individual's respiratory cycle to the chemicals that may be present in their breath. This review paper provides an overview of recent developments in TENG-based wearable respiratory monitoring as well as future opportunities and challenges for respiratory healthcare.</p>","PeriodicalId":100533,"journal":{"name":"FlexMat","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/flm2.10","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140643462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yingxin Zhang, Bing Xu, Feifei Zhao, Haizeng Li, Jingwei Chen, Huanlei Wang, William W. Yu
Electrochromic technology has recently made many achievements in research and commercialization. Electrochromic devices are being developed based on various coating and printing methods for multipronged applications, and have great potential for next-generation flexible electronics. Compared to other coating and printing techniques, inkjet printing (IJP) enables non-contact patterning on a variety of substrates by programming the movement of the printing nozzle. IJP has great advantages in printing smart electrochromic devices because of its low cost, high resolution, high material utilization rate, and applicability to various large-size substrates. In this review, the principles and process of IJP and the latest progress of IJP in electrochromic devices are summarized in detail. IJP of electrochromic materials, conductive contacts, and blocking layers are discussed. IJP assisted fabrication of smart electrochromic displays, flexible and stretchable electrochromic devices, electrochromic-energy storage, smart windows, and others are also demonstrated. The problems and challenges faced by IJP electrochromic devices are emphasized, and the future development trends are prospected. This review aims at further promoting the development of IJP for smart electrochromic devices and encouraging future applications of IJP and electrochromic devices in the era of Internet of Things.
{"title":"Inkjet printing for smart electrochromic devices","authors":"Yingxin Zhang, Bing Xu, Feifei Zhao, Haizeng Li, Jingwei Chen, Huanlei Wang, William W. Yu","doi":"10.1002/flm2.11","DOIUrl":"https://doi.org/10.1002/flm2.11","url":null,"abstract":"<p>Electrochromic technology has recently made many achievements in research and commercialization. Electrochromic devices are being developed based on various coating and printing methods for multipronged applications, and have great potential for next-generation flexible electronics. Compared to other coating and printing techniques, inkjet printing (IJP) enables non-contact patterning on a variety of substrates by programming the movement of the printing nozzle. IJP has great advantages in printing smart electrochromic devices because of its low cost, high resolution, high material utilization rate, and applicability to various large-size substrates. In this review, the principles and process of IJP and the latest progress of IJP in electrochromic devices are summarized in detail. IJP of electrochromic materials, conductive contacts, and blocking layers are discussed. IJP assisted fabrication of smart electrochromic displays, flexible and stretchable electrochromic devices, electrochromic-energy storage, smart windows, and others are also demonstrated. The problems and challenges faced by IJP electrochromic devices are emphasized, and the future development trends are prospected. This review aims at further promoting the development of IJP for smart electrochromic devices and encouraging future applications of IJP and electrochromic devices in the era of Internet of Things.</p>","PeriodicalId":100533,"journal":{"name":"FlexMat","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/flm2.11","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140643463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mingxu Du, Yang Chen, Minqiang Mai, Tianjiao Fan, Qian Jin, Yuewei Zhang, Lian Duan
Recently, a novel paradigm of boron- and nitrogen-embedded polycyclic nanographites featuring multiple resonance thermally activated delayed fluorescence (MR-TADF) has garnered substantial interest due to their extraordinary attributes of efficient narrowband emissions with small full width at half maxima (FWHMs). Despite an array of diverse color tuning strategies, it remains elusive how to effectively manipulate device efficiencies without altering the materials' intrinsic MR-TADF characteristics. Here, an advanced ‘non-conjugate fusion’ design methodology was proposed, aimed at dramatically amplifying the horizontal orientations of MR-TADF emitters while preserving the short-range charge-transfer properties. As envisioned, when compared to the classical BCz-BN mother core, the proof-of-concept emitter mICz-BN achieved an impressively enhanced horizontal dipole ratio (83% vs. 75%) at analogous emission wavelengths (∼486 nm), FWHMs (∼26 nm) and photoluminescence quantum yields (∼93%). Consequently, the external quantum efficiency of the optimized device yielded a performance enhancement of 1.2-fold (30.5% vs. 25.3%) whilst keeping the spectrum almost unchanged.
{"title":"Understanding and modulating the horizontal orientations and short-range charge transfer excited states for high-performance narrowband emitters","authors":"Mingxu Du, Yang Chen, Minqiang Mai, Tianjiao Fan, Qian Jin, Yuewei Zhang, Lian Duan","doi":"10.1002/flm2.15","DOIUrl":"https://doi.org/10.1002/flm2.15","url":null,"abstract":"<p>Recently, a novel paradigm of boron- and nitrogen-embedded polycyclic nanographites featuring multiple resonance thermally activated delayed fluorescence (MR-TADF) has garnered substantial interest due to their extraordinary attributes of efficient narrowband emissions with small full width at half maxima (FWHMs). Despite an array of diverse color tuning strategies, it remains elusive how to effectively manipulate device efficiencies without altering the materials' intrinsic MR-TADF characteristics. Here, an advanced ‘non-conjugate fusion’ design methodology was proposed, aimed at dramatically amplifying the horizontal orientations of MR-TADF emitters while preserving the short-range charge-transfer properties. As envisioned, when compared to the classical BCz-BN mother core, the proof-of-concept emitter mICz-BN achieved an impressively enhanced horizontal dipole ratio (<b>83%</b> vs. 75%) at analogous emission wavelengths (∼486 nm), FWHMs (∼26 nm) and photoluminescence quantum yields (∼93%). Consequently, the external quantum efficiency of the optimized device yielded a performance enhancement of 1.2-fold (<b>30.5%</b> vs. 25.3%) whilst keeping the spectrum almost unchanged.</p>","PeriodicalId":100533,"journal":{"name":"FlexMat","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/flm2.15","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140648127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}