Rita Butkute, Ausrine Masiulyte, Ehsan Ullah Rashid, Svetlana Sargsyan, Neelalohith Satish Moudgalya, Karolis Leitonas, Dmytro Volyniuk and Juozas V. Grazulevicius*,
Seeking to develop more advanced organic photodetectors (OPDs) and organic light-emitting diodes (OLEDs), we designed three derivatives of 2,7-di-tert-butyl-9,9-dimethyl-9,10-dihydroacridine and phenanthroimidazole with either −CF3 or −C(CH3)3 groups. These compounds were synthesized by Buchwald–Hartwig amination reaction with yields of up to 77%. They show high glass transition temperatures above 200 °C and balanced electron and hole transport with mobilities of up to 10–3 cm2/V·s under strong electric fields. One compound with −C(CH3)3 groups outperformed the standard host material in the OLED, which showed 17% higher external quantum efficiency. The low dark current density resulted in enhanced efficiency of OLEDs due to minimal charge leakage. Compared to the commercial material 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC), this compound allowed achieving superior photosensitivity in OPDs. The photocurrent to dark current density ratio at a reverse voltage of −10 V was found to be 6000. For TAPC-based OPDs, this ratio was only 43.3. The dark current density was significantly reduced to 4.5 × 10–7 mA·cm–2, compared to 3 × 10–4 mA·cm–2 for TAPC-based OPDs at the same reverse voltage, thus enhancing the photosensitivity of the OPDs.
{"title":"Ultralow Dark Current Density of Organic Photodetectors and Organic Light-Emitting Diodes Endowed by Highly Thermally Stable Derivatives of 2,7-Di-tert-butyl-9,9-dimethyl-9,10-dihydroacridine and Phenanthroimidazole Exhibiting Balanced Bipolar Charge Transport","authors":"Rita Butkute, Ausrine Masiulyte, Ehsan Ullah Rashid, Svetlana Sargsyan, Neelalohith Satish Moudgalya, Karolis Leitonas, Dmytro Volyniuk and Juozas V. Grazulevicius*, ","doi":"10.1021/acsaelm.4c00746","DOIUrl":"10.1021/acsaelm.4c00746","url":null,"abstract":"<p >Seeking to develop more advanced organic photodetectors (OPDs) and organic light-emitting diodes (OLEDs), we designed three derivatives of 2,7-di-<i>tert</i>-butyl-9,9-dimethyl-9,10-dihydroacridine and phenanthroimidazole with either −CF<sub>3</sub> or −C(CH<sub>3</sub>)<sub>3</sub> groups. These compounds were synthesized by Buchwald–Hartwig amination reaction with yields of up to 77%. They show high glass transition temperatures above 200 °C and balanced electron and hole transport with mobilities of up to 10<sup>–3</sup> cm<sup>2</sup>/V·s under strong electric fields. One compound with −C(CH<sub>3</sub>)<sub>3</sub> groups outperformed the standard host material in the OLED, which showed 17% higher external quantum efficiency. The low dark current density resulted in enhanced efficiency of OLEDs due to minimal charge leakage. Compared to the commercial material 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC), this compound allowed achieving superior photosensitivity in OPDs. The photocurrent to dark current density ratio at a reverse voltage of −10 V was found to be 6000. For TAPC-based OPDs, this ratio was only 43.3. The dark current density was significantly reduced to 4.5 × 10<sup>–7</sup> mA·cm<sup>–2</sup>, compared to 3 × 10<sup>–4</sup> mA·cm<sup>–2</sup> for TAPC-based OPDs at the same reverse voltage, thus enhancing the photosensitivity of the OPDs.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsaelm.4c00746","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141349755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yufei Tian, Maolin Dong, Xin Wang, Yihua Zhou* and Jun Qian*,
There is a high demand for the design of high-performance electrothermal devices, including electrothermal films and actuators, with easy fabrication and low cost. Herein, flexible electrothermal films made of polyimide and carbon nanomaterials and bimorph actuators consisting of polythene and carbon nanomaterials are fabricated by a handwriting technique with a whiteboard marker pen filled with carbon aqueous conductive ink, which is simple and scalable. The electrical performance was examined through lightning diodes by drawing traces on various substrates to form a circuit. In addition, the performance of prepared handwritten devices was compared to that of screen-printed devices, and it was discovered that their performance was similar. The prepared electrothermal films can reach 122 °C with 10 V, and the bimorph actuator exhibits electrical actuation with reversible deformation of 221° under 5 V voltage within 20 s. Furthermore, a cross pattern composed of four pieces of the actuator was fabricated to demonstrate electrically driven actuation. These works provide a simple and fast method to fabricate electrothermal devices for intelligent fields and practical applications.
人们对高性能电热器件(包括电热膜和致动器)的设计提出了更高的要求,这些器件不仅易于制造,而且成本低廉。在此,我们采用一种简单且可扩展的手写技术,用白板笔填充碳水导电墨水,制作了由聚酰亚胺和碳纳米材料制成的柔性电热膜,以及由聚乙烯和碳纳米材料组成的双态致动器。通过在不同基底上绘制迹线形成电路,对雷电二极管的电气性能进行了检验。此外,还将制备的手写器件的性能与丝网印刷器件的性能进行了比较,发现两者的性能相似。制备的电热膜在 10 V 电压下温度可达 122 °C,双态致动器在 5 V 电压下 20 秒内可实现 221° 的可逆形变。这些工作为智能领域和实际应用提供了一种简单、快速的电热器件制造方法。
{"title":"Fully Handwritten Flexible Electrothermal Devices Using a Whiteboard Marker Pen with Carbon Nanoparticle Ink","authors":"Yufei Tian, Maolin Dong, Xin Wang, Yihua Zhou* and Jun Qian*, ","doi":"10.1021/acsaelm.4c00375","DOIUrl":"10.1021/acsaelm.4c00375","url":null,"abstract":"<p >There is a high demand for the design of high-performance electrothermal devices, including electrothermal films and actuators, with easy fabrication and low cost. Herein, flexible electrothermal films made of polyimide and carbon nanomaterials and bimorph actuators consisting of polythene and carbon nanomaterials are fabricated by a handwriting technique with a whiteboard marker pen filled with carbon aqueous conductive ink, which is simple and scalable. The electrical performance was examined through lightning diodes by drawing traces on various substrates to form a circuit. In addition, the performance of prepared handwritten devices was compared to that of screen-printed devices, and it was discovered that their performance was similar. The prepared electrothermal films can reach 122 °C with 10 V, and the bimorph actuator exhibits electrical actuation with reversible deformation of 221° under 5 V voltage within 20 s. Furthermore, a cross pattern composed of four pieces of the actuator was fabricated to demonstrate electrically driven actuation. These works provide a simple and fast method to fabricate electrothermal devices for intelligent fields and practical applications.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141348201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bohan Hao, Yanda Zhu, Yiming Xia, Qingxiao Meng, Han Zhang, Xi Lin, Yangfan Zhang, Bo Qu, Peiyuan Guan, Junjie Shi, Wenxian Li* and Sean Li,
Transparent flexible resistive sensors have generated significant interest within the rapidly evolving field of stretchable electronics, particularly for applications that require transparency, fatigue resistance, and high sensitivity. Our research proposed a screen-printing strategy to produce transparent flexible resistive sensors characterized by their sensitive responses to droplet variations and endowed with the capability for repeated utilization utilizing silver nanowires (AgNWs) ink and polyethylene terephthalate (PET) substrate. Plasma treatment was implemented to enhance the electrical conductivity of the printed circuit, which can fuse the AgNWs into highly connected frameworks without deteriorating the transmittance properties of the circuit board. Additionally, the cyclic stability in the solution was improved by applying a carbon coating on the AgNWs-based sensors facilitated by the shadow mask. The resistive sensors demonstrate varied current responses when exposed to liquids with differing conductivity levels while maintaining excellent optical performance with an average transmittance of 77.6% at a visible wavelength of 550 nm. The transparent flexible sensors exhibit prospective applications in biomedical sensing, industrial process control, and intelligent packaging for food safety, thereby providing a thought for the next generation of artificial sensors.
{"title":"Screen-Printed Transparent Flexible Sensors for Liquid Solvent Detection","authors":"Bohan Hao, Yanda Zhu, Yiming Xia, Qingxiao Meng, Han Zhang, Xi Lin, Yangfan Zhang, Bo Qu, Peiyuan Guan, Junjie Shi, Wenxian Li* and Sean Li, ","doi":"10.1021/acsaelm.4c00271","DOIUrl":"10.1021/acsaelm.4c00271","url":null,"abstract":"<p >Transparent flexible resistive sensors have generated significant interest within the rapidly evolving field of stretchable electronics, particularly for applications that require transparency, fatigue resistance, and high sensitivity. Our research proposed a screen-printing strategy to produce transparent flexible resistive sensors characterized by their sensitive responses to droplet variations and endowed with the capability for repeated utilization utilizing silver nanowires (AgNWs) ink and polyethylene terephthalate (PET) substrate. Plasma treatment was implemented to enhance the electrical conductivity of the printed circuit, which can fuse the AgNWs into highly connected frameworks without deteriorating the transmittance properties of the circuit board. Additionally, the cyclic stability in the solution was improved by applying a carbon coating on the AgNWs-based sensors facilitated by the shadow mask. The resistive sensors demonstrate varied current responses when exposed to liquids with differing conductivity levels while maintaining excellent optical performance with an average transmittance of 77.6% at a visible wavelength of 550 nm. The transparent flexible sensors exhibit prospective applications in biomedical sensing, industrial process control, and intelligent packaging for food safety, thereby providing a thought for the next generation of artificial sensors.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141348145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nileshkumar M. Pardeshi, Rahul S. Ghuge, Priyanka N. Birla, Ratna Chauhan, Shyamal P. Bhalekar, Manish D. Shinde*, Yuvaraj Sivalingam, Rajendra D. Kale* and Sunit B. Rane,
Metal oxide nanomaterials possess an exceptional physical and chemical behavior apposite for gas-sensing applications. Among them, titanium dioxide (TiO2) is a promising, robust, and economical material, and when paired with two-dimensional (2D) materials such as reduced graphene oxide (rGO), the resultant composite system is promoted to an interesting gas-sensing candidate. Properties of rGO- and TiO2-based nanocomposites depend on the size and shape of TiO2 nanoparticles and the weight percentage (wt %) ratio of rGO/TiO2. Herein, the preparation of rGO@bimodal TiO2 nanocomposites (hereafter referred to as G@TiO2) by the conventional hydrothermal method having different wt % (1, 2.5, 5, and 10) of rGO with bimodal TiO2 nanoparticles is reported. Structural, optical, morphological, and microstructural characterizations of the prepared nanocomposites revealed the generation of elongated submicron particles and nanorods of bimodal TiO2 in the G@TiO2 samples. The gas sensors based on the prepared materials were fabricated to evaluate their gas-sensing properties. The comparative analysis illustrated that the sensor based on 2.5%G@TiO2 presented the highest sensitivity and selectivity to n-butanol at room temperature (25 °C). Furthermore, supplemental investigation on n-butanol adsorption properties of all sensors was carried out using a scanning Kelvin probe (SKP) technique, which further corroborated the exceptional n-butanol adsorption (>2 times) for the 2.5%G@TiO2 surface at room temperature.
{"title":"Reduced Graphene Oxide@Bimodal TiO2 Nanocomposites as an Efficacious Console for Room Temperature n-Butanol Gas Sensing","authors":"Nileshkumar M. Pardeshi, Rahul S. Ghuge, Priyanka N. Birla, Ratna Chauhan, Shyamal P. Bhalekar, Manish D. Shinde*, Yuvaraj Sivalingam, Rajendra D. Kale* and Sunit B. Rane, ","doi":"10.1021/acsaelm.4c00849","DOIUrl":"10.1021/acsaelm.4c00849","url":null,"abstract":"<p >Metal oxide nanomaterials possess an exceptional physical and chemical behavior apposite for gas-sensing applications. Among them, titanium dioxide (TiO<sub>2</sub>) is a promising, robust, and economical material, and when paired with two-dimensional (2D) materials such as reduced graphene oxide (rGO), the resultant composite system is promoted to an interesting gas-sensing candidate. Properties of rGO- and TiO<sub>2</sub>-based nanocomposites depend on the size and shape of TiO<sub>2</sub> nanoparticles and the weight percentage (wt %) ratio of rGO/TiO<sub>2</sub>. Herein, the preparation of rGO@bimodal TiO<sub>2</sub> nanocomposites (hereafter referred to as G@TiO<sub>2</sub>) by the conventional hydrothermal method having different wt % (1, 2.5, 5, and 10) of rGO with bimodal TiO<sub>2</sub> nanoparticles is reported. Structural, optical, morphological, and microstructural characterizations of the prepared nanocomposites revealed the generation of elongated submicron particles and nanorods of bimodal TiO<sub>2</sub> in the G@TiO<sub>2</sub> samples. The gas sensors based on the prepared materials were fabricated to evaluate their gas-sensing properties. The comparative analysis illustrated that the sensor based on 2.5%G@TiO<sub>2</sub> presented the highest sensitivity and selectivity to <i>n</i>-butanol at room temperature (25 °C). Furthermore, supplemental investigation on <i>n</i>-butanol adsorption properties of all sensors was carried out using a scanning Kelvin probe (SKP) technique, which further corroborated the exceptional <i>n</i>-butanol adsorption (>2 times) for the 2.5%G@TiO<sub>2</sub> surface at room temperature.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141346020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samira Mohammadi, and , Seyed Morteza Mousavi-Khoshdel*,
In this study, using graphene oxide (GO), glutamine (G), and Cu(II) nanoparticles, a nanocomposite was prepared. Then, the prepared nanocomposite was checked out by various techniques such as X-ray diffraction, Fourier transform infrared, Raman spectrum, scanning electron microscopy, and energy-dispersive X-ray, and the results showed that the desired structure was successfully prepared. Also, a three-electrode system was utilized to measure the electrochemical properties. The specific capacitance of a Cu-doped graphene oxide-glutamine nanocomposite (Cu/G-GO) of 1838 F g–1 was obtained in a 1 M H2SO4 aqueous electrolyte under a current density of 3 A g–1. Moreover, 85.43% of the initial capacitance of the electrode was preserved after 5000 cycles at 20 A g–1 (10,000 cycles, 73.12%). Also, the quantum capacitance and the layer distance of GO and G-GO using density functional theory were calculated.
本研究利用氧化石墨烯(GO)、谷氨酰胺(G)和铜(II)纳米粒子制备了一种纳米复合材料。然后,利用 X 射线衍射、傅立叶变换红外线、拉曼光谱、扫描电子显微镜和能量色散 X 射线等多种技术对制备的纳米复合材料进行了检测,结果表明成功制备了所需的结构。此外,还利用三电极系统测量了电化学特性。在电流密度为 3 A g-1 的 1 M H2SO4 水电解质中,掺铜氧化石墨烯-谷氨酰胺纳米复合材料(Cu/G-GO)的比电容为 1838 F g-1。此外,在 20 A g-1 条件下循环 5000 次后,电极初始电容的 85.43% 得以保留(循环 10000 次,73.12%)。此外,还利用密度泛函理论计算了 GO 和 G-GO 的量子电容和层间距。
{"title":"Preparation of a Cu-Doped Graphene Oxide–Glutamine Nanocomposite for Supercapacitor Electrode Applications: An Experimental and Theoretical Study","authors":"Samira Mohammadi, and , Seyed Morteza Mousavi-Khoshdel*, ","doi":"10.1021/acsaelm.4c00224","DOIUrl":"10.1021/acsaelm.4c00224","url":null,"abstract":"<p >In this study, using graphene oxide (GO), glutamine (G), and Cu(II) nanoparticles, a nanocomposite was prepared. Then, the prepared nanocomposite was checked out by various techniques such as X-ray diffraction, Fourier transform infrared, Raman spectrum, scanning electron microscopy, and energy-dispersive X-ray, and the results showed that the desired structure was successfully prepared. Also, a three-electrode system was utilized to measure the electrochemical properties. The specific capacitance of a Cu-doped graphene oxide-glutamine nanocomposite (Cu/G-GO) of 1838 F g<sup>–1</sup> was obtained in a 1 M H<sub>2</sub>SO<sub>4</sub> aqueous electrolyte under a current density of 3 A g<sup>–1</sup>. Moreover, 85.43% of the initial capacitance of the electrode was preserved after 5000 cycles at 20 A g<sup>–1</sup> (10,000 cycles, 73.12%). Also, the quantum capacitance and the layer distance of GO and G-GO using density functional theory were calculated.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141352817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dingming Yang, Jiahao Xue, Jing Wang, Hao Wang, Shulong Wang, Xiaoyi Lei*, Junfeng Yan and Wu Zhao,
Current overshoot in resistive random access memory (RRAM) can affect the stability and increase the power consumption of devices, which has become a great challenge in RRAM applications. In this study, we analyzed current overshoot in Ti/ZrO2/Pt devices and proposed a solution to improve device stability through high-temperature forming. The analysis results indicate that current overshoot is likely to occur in the RESET process when the SET voltage is too high, and temperature has an important impact on the conversion voltage of the Ti/ZrO2/Pt devices. Moreover, we established an electrothermal coupling model of the devices based on the oxygen vacancy conduction mechanism by COMSOL, which could obtain the distribution of the oxygen vacancy concentration in the dielectric layer during resistance conversion at different temperatures and electric fields. Based on the above analysis, by forming at high temperature, the overshoot current is reduced, and the stability of the switching voltage is improved successfully.
{"title":"Uniformity Improvement of Ti/ZrO2/Pt RRAM by Analyzing and Reducing Current Overshoot","authors":"Dingming Yang, Jiahao Xue, Jing Wang, Hao Wang, Shulong Wang, Xiaoyi Lei*, Junfeng Yan and Wu Zhao, ","doi":"10.1021/acsaelm.4c00790","DOIUrl":"10.1021/acsaelm.4c00790","url":null,"abstract":"<p >Current overshoot in resistive random access memory (RRAM) can affect the stability and increase the power consumption of devices, which has become a great challenge in RRAM applications. In this study, we analyzed current overshoot in Ti/ZrO<sub>2</sub>/Pt devices and proposed a solution to improve device stability through high-temperature forming. The analysis results indicate that current overshoot is likely to occur in the RESET process when the SET voltage is too high, and temperature has an important impact on the conversion voltage of the Ti/ZrO<sub>2</sub>/Pt devices. Moreover, we established an electrothermal coupling model of the devices based on the oxygen vacancy conduction mechanism by COMSOL, which could obtain the distribution of the oxygen vacancy concentration in the dielectric layer during resistance conversion at different temperatures and electric fields. Based on the above analysis, by forming at high temperature, the overshoot current is reduced, and the stability of the switching voltage is improved successfully.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141350756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oleksandr Bezvikonnyi, Audrius Bucinskas, Pavel Arsenyan*, Alla Petrenko, Zheng-Yu Wei, Jiun-Haw Lee, Dmytro Volyniuk, Ehsan Ullah Rashid, Tien-Lung Chiu* and Juozas Vidas Grazulevicius*,
Carbazoles with tert-butyl, methoxy, and methoxyethoxy groups are linked with anthracene-based moieties in a series of designed and synthesized compounds with the aim to obtain triplet levels lower than 2 eV and efficient triplet harvesting in electroluminescent devices. The upconversion of triplet excitons is studied theoretically and experimentally. The triplet fusion is responsible for the appearance of blue delayed emission with lifetimes up to 0.15 ms, which is detected for the methoxy-containing compound by photophysical investigation. The tert-butylated emitter shows good performance in organic light emitting diodes (OLEDs), reaching an external quantum efficiency of 5.9% with the 1931 Commission Internationale de l’Éclairage coordinates of (0.14, 0.12). The time-of-flight measurements demonstrate that the derivative of tert-butylcarbazolyl and anthracene is the most promising candidate for electronic devices due to its high hole mobility, reaching 7.6 × 10–5 cm2/(V s) at an electric field of 8 × 105 V/cm. Exploitation of a guest–host containing the tert-butylcarbazolyl and anthracene derivative as a host exhibiting triplet–triplet annihilation (TTA) and a fluorescent emitter resulted in an efficient hyperfluorescent OLED with a maximum external quantum efficiency of 7.1%. The OLED with such efficiency outperformed the theoretical limit of conventional fluorescence-based devices due to the utilization of triplet excitons in emission allocated to TTA upconverted excitons.
{"title":"Enhancement of Blue Doping-Free and Hyperfluorescent Organic Light Emitting Diode Performance through Triplet–Triplet Annihilation in the Derivatives of Anthracene and Carbazole","authors":"Oleksandr Bezvikonnyi, Audrius Bucinskas, Pavel Arsenyan*, Alla Petrenko, Zheng-Yu Wei, Jiun-Haw Lee, Dmytro Volyniuk, Ehsan Ullah Rashid, Tien-Lung Chiu* and Juozas Vidas Grazulevicius*, ","doi":"10.1021/acsaelm.4c00533","DOIUrl":"10.1021/acsaelm.4c00533","url":null,"abstract":"<p >Carbazoles with <i>tert</i>-butyl, methoxy, and methoxyethoxy groups are linked with anthracene-based moieties in a series of designed and synthesized compounds with the aim to obtain triplet levels lower than 2 eV and efficient triplet harvesting in electroluminescent devices. The upconversion of triplet excitons is studied theoretically and experimentally. The triplet fusion is responsible for the appearance of blue delayed emission with lifetimes up to 0.15 ms, which is detected for the methoxy-containing compound by photophysical investigation. The <i>tert</i>-butylated emitter shows good performance in organic light emitting diodes (OLEDs), reaching an external quantum efficiency of 5.9% with the 1931 Commission Internationale de l’Éclairage coordinates of (0.14, 0.12). The time-of-flight measurements demonstrate that the derivative of <i>tert</i>-butylcarbazolyl and anthracene is the most promising candidate for electronic devices due to its high hole mobility, reaching 7.6 × 10<sup>–5</sup> cm<sup>2</sup>/(V s) at an electric field of 8 × 10<sup>5</sup> V/cm. Exploitation of a guest–host containing the <i>tert</i>-butylcarbazolyl and anthracene derivative as a host exhibiting triplet–triplet annihilation (TTA) and a fluorescent emitter resulted in an efficient hyperfluorescent OLED with a maximum external quantum efficiency of 7.1%. The OLED with such efficiency outperformed the theoretical limit of conventional fluorescence-based devices due to the utilization of triplet excitons in emission allocated to TTA upconverted excitons.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsaelm.4c00533","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141351423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xue Zhang, Fan Zhang*, Yiwen Niu, Zhiqiang Zhang, Xueqiong Lei and Zhan Jie Wang,
Due to the typical dielectric relaxation behavior of perovskite high-entropy ceramics (HECs), high-entropy engineering is beneficial for improving energy storage performance and has drawn extensive concern. In this study, high-entropy oxide (Bi0.2Na0.2Ba0.2Sr0.2Ca0.2)(Ti0.9Nb0.1)O3 (BNCBSTN)-modified 0.45(Bi0.5Na0.5)TiO3-0.55(Sr0.7Bi0.2)TiO3 (BNT-SBT) systems, BNT-SBT-xBNCBSTN (0 ≤ x ≤ 0.5) ceramics, were designed and prepared using a hydrothermal method. It is found that the introduction of BNCBSTN into BNT-SBT promotes the configuration entropy and induces strong dielectric relaxation behavior, thereby greatly improving the energy storage performance. In addition, grain refinement, increased resistivity, and widened band gap are achieved by the modification of BNCBSTN, leading to a significant enhancement of the breakdown electric field (Eb). Consequently, BNT-SBT-0.3BNCBSTN HEC exhibits a preeminent recoverable energy density (Wrec = 6.04 J/cm3) and energy storage efficiency (η = 85%) under an excellent Eb of 410 kV/cm as well as good temperature and frequency stability. The remarkable improvement in energy storage performance indicates that modifying the ferroelectric system with high-entropy oxide is a feasible approach for developing energy storage capacitors.
{"title":"Excellent Energy Storage Performance of Perovskite High-Entropy Oxide-Modified (Bi0.5Na0.5)TiO3-Based Ceramics","authors":"Xue Zhang, Fan Zhang*, Yiwen Niu, Zhiqiang Zhang, Xueqiong Lei and Zhan Jie Wang, ","doi":"10.1021/acsaelm.4c00679","DOIUrl":"10.1021/acsaelm.4c00679","url":null,"abstract":"<p >Due to the typical dielectric relaxation behavior of perovskite high-entropy ceramics (HECs), high-entropy engineering is beneficial for improving energy storage performance and has drawn extensive concern. In this study, high-entropy oxide (Bi<sub>0.2</sub>Na<sub>0.2</sub>Ba<sub>0.2</sub>Sr<sub>0.2</sub>Ca<sub>0.2</sub>)(Ti<sub>0.9</sub>Nb<sub>0.1</sub>)O<sub>3</sub> (BNCBSTN)-modified 0.45(Bi<sub>0.5</sub>Na<sub>0.5</sub>)TiO<sub>3</sub>-0.55(Sr<sub>0.7</sub>Bi<sub>0.2</sub>)TiO<sub>3</sub> (BNT-SBT) systems, BNT-SBT-<i>x</i>BNCBSTN (0 ≤ <i>x</i> ≤ 0.5) ceramics, were designed and prepared using a hydrothermal method. It is found that the introduction of BNCBSTN into BNT-SBT promotes the configuration entropy and induces strong dielectric relaxation behavior, thereby greatly improving the energy storage performance. In addition, grain refinement, increased resistivity, and widened band gap are achieved by the modification of BNCBSTN, leading to a significant enhancement of the breakdown electric field (<i>E</i><sub>b</sub>). Consequently, BNT-SBT-0.3BNCBSTN HEC exhibits a preeminent recoverable energy density (<i>W</i><sub>rec</sub> = 6.04 J/cm<sup>3</sup>) and energy storage efficiency (η = 85%) under an excellent <i>E</i><sub>b</sub> of 410 kV/cm as well as good temperature and frequency stability. The remarkable improvement in energy storage performance indicates that modifying the ferroelectric system with high-entropy oxide is a feasible approach for developing energy storage capacitors.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141351963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrew D. M. Charles*, Andrew N. Rider, Sonya A. Brown and Chun H. Wang,
Polymer-based magnetoelectric materials form a technologically significant class of magneto-polymer composites which show promise for the production of low-cost and mechanically durable sensors, energy harvesters, and transducers. The use of a particle magnetostrictive phase in these composites offers a scalable path to producing large-area magnetoelectric materials and, so, is highly attractive. A key challenge for these composites is improving the coupling between the particle and polymer phases. In this work, we explore the use of shape anisotropy in galfenol flake particles as a means of bestowing magnetoelectric anisotropy. Cryogenic ball milling is used as a means to produce particulates, which are distributed and aligned in P(VDF-TrFE) composite films. A direction-specific, bias-free magnetoelectric coupling as high as 46.27 mV/cm·Oe was achieved. The use of this material in an energy harvesting device yielded peak energy harvesting power densities of 46.97 and 2.03 μW/cm3 for vibrational and magnetic fields, respectively.
{"title":"Creating High Aspect Ratio Magnetostrictive Flakes to Enhance Magnetoelectric Polymer Composites","authors":"Andrew D. M. Charles*, Andrew N. Rider, Sonya A. Brown and Chun H. Wang, ","doi":"10.1021/acsaelm.4c00594","DOIUrl":"10.1021/acsaelm.4c00594","url":null,"abstract":"<p >Polymer-based magnetoelectric materials form a technologically significant class of magneto-polymer composites which show promise for the production of low-cost and mechanically durable sensors, energy harvesters, and transducers. The use of a particle magnetostrictive phase in these composites offers a scalable path to producing large-area magnetoelectric materials and, so, is highly attractive. A key challenge for these composites is improving the coupling between the particle and polymer phases. In this work, we explore the use of shape anisotropy in galfenol flake particles as a means of bestowing magnetoelectric anisotropy. Cryogenic ball milling is used as a means to produce particulates, which are distributed and aligned in P(VDF-TrFE) composite films. A direction-specific, bias-free magnetoelectric coupling as high as 46.27 mV/cm·Oe was achieved. The use of this material in an energy harvesting device yielded peak energy harvesting power densities of 46.97 and 2.03 μW/cm<sup>3</sup> for vibrational and magnetic fields, respectively.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141357583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Durga Prasad Pabba, J. Kaarthik, Nayak Ram and Annapureddy Venkateswarlu*,
Combining the effects of magnetostrictive and piezoelectric, magneto-mechano-electrical (MME) generators have been developed to accomplish stray magnetic field harvesting for noncontact energy harvesting applications. The highly magnetostrictive interaction boosted the output performance of the MME generator in response to external magnetic stimulation. In this study, MME generators were developed using piezoelectric-ferromagnetic (PVDF/BZT-BCT-ferrite) electrospun fiber-based composites. The autocombustion process was employed to prepare nickel ferrite and cobalt ferrite nanoparticles with average crystallite sizes of 35 and 40 nm, respectively. XRD and FTIR analysis of fiber-based composites revealed a significant increase in the electroactive β-phase due to the electrostatic interaction between the inorganic materials and PVDF. FESEM micrographs demonstrated the formation of homogeneous bead-free fibers, whereas EDS proved the elemental presence of BCT-BZT and ferrite in the composite fibers. We optimized the magnetic field conversion efficiency in the MME generator by varying the magnetostrictive material through direct particle–particle connection in the fiber composite and then layer-by-layer connection. The optimized MME nanogenerator effectively harvests magnetic fields, yielding an output voltage and power density of 6.2 V and 88.7 μW/m2, respectively, under an AC magnetic field of 6 Oe at 50 Hz. This represents a significant improvement of 385% compared to conventional generators. This MME device shows great promise for providing substantial power to implantable wireless sensor network devices.
{"title":"Harnessing the Induced Magnetostrictive Effect in Fully Flexible Fiber-Based Magnetoelectric Composites for Improved Stray Magnetic Energy Harvesting","authors":"Durga Prasad Pabba, J. Kaarthik, Nayak Ram and Annapureddy Venkateswarlu*, ","doi":"10.1021/acsaelm.4c00825","DOIUrl":"10.1021/acsaelm.4c00825","url":null,"abstract":"<p >Combining the effects of magnetostrictive and piezoelectric, magneto-mechano-electrical (MME) generators have been developed to accomplish stray magnetic field harvesting for noncontact energy harvesting applications. The highly magnetostrictive interaction boosted the output performance of the MME generator in response to external magnetic stimulation. In this study, MME generators were developed using piezoelectric-ferromagnetic (PVDF/BZT-BCT-ferrite) electrospun fiber-based composites. The autocombustion process was employed to prepare nickel ferrite and cobalt ferrite nanoparticles with average crystallite sizes of 35 and 40 nm, respectively. XRD and FTIR analysis of fiber-based composites revealed a significant increase in the electroactive β-phase due to the electrostatic interaction between the inorganic materials and PVDF. FESEM micrographs demonstrated the formation of homogeneous bead-free fibers, whereas EDS proved the elemental presence of BCT-BZT and ferrite in the composite fibers. We optimized the magnetic field conversion efficiency in the MME generator by varying the magnetostrictive material through direct particle–particle connection in the fiber composite and then layer-by-layer connection. The optimized MME nanogenerator effectively harvests magnetic fields, yielding an output voltage and power density of 6.2 V and 88.7 μW/m<sup>2</sup>, respectively, under an AC magnetic field of 6 Oe at 50 Hz. This represents a significant improvement of 385% compared to conventional generators. This MME device shows great promise for providing substantial power to implantable wireless sensor network devices.</p>","PeriodicalId":3,"journal":{"name":"ACS Applied Electronic Materials","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141358092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}