Organic Electronics最新文献

{"title":"Efficient greenish-blue thermally activated delayed fluorescence Zn complex for organic light emitting devices","authors":"Chih-Pin Han ,&nbsp;Chao-Hsien Hsu ,&nbsp;Ching-Yuan Chu ,&nbsp;Tzu-Hao Huang ,&nbsp;Chih-Lun Yi ,&nbsp;Ken-Tsung Wong ,&nbsp;Jake A. Tan ,&nbsp;Wen-Yi Hung ,&nbsp;Man-kit Leung ,&nbsp;Pi-Tai Chou","doi":"10.1016/j.orgel.2024.107178","DOIUrl":"10.1016/j.orgel.2024.107178","url":null,"abstract":"<div><div>A greenish-blue zinc complex <strong>Zn(PhOBz)-PXZ</strong> with enhanced thermally activated delayed fluorescence (TADF) properties has been prepared from Zn(OAc)₂ and <strong>4PXZ2OHBz</strong>, a 2-(1<em>H</em>-benzimidazol-2-yl)phenol-based TADF ligand. The TADF phenomenon has been confirmed by time-resolved photoluminescence (TrPL) studies. The DFT calculations show spatially well-separated HOMO and LUMO in their ground states, along with a small energy splitting between the excited singlet (S₁) and triplet (T₁) states, in a good agreement with the TADF mechanism. Due to the high thermal stability of <strong>Zn(PhOBz)-PXZ</strong>, OLED devices can be fabricated by vacuum vapor deposition, and greenish-blue OLEDs with the maximum emission at 521 nm were successfully demonstrated. The maximum external quantum efficiency (EQE_max) of 10.6 %, with Commission Internationale de l’Eclairage (CIE) coordinates of (0.28, 0.47) were recorded. Zinc TADF complexes have the advantages of cost-effectiveness, greater abundance of natural resources, environmentally friendly metals, making them potential replacements for future precious metal emitters.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"138 ","pages":"Article 107178"},"PeriodicalIF":2.7,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143156575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overcoming light loss in semi-transparent ternary organic solar cells with ultra-thin metal electrodes","authors":"Chih-Ping Chen ,&nbsp;Chun-Chieh Lee ,&nbsp;Bing-Huang Jiang ,&nbsp;Ming-Wei Hsu ,&nbsp;Yang-Yen Yu","doi":"10.1016/j.orgel.2024.107174","DOIUrl":"10.1016/j.orgel.2024.107174","url":null,"abstract":"<div><div>Organic photovoltaics (OPVs) hold promise as renewable energy sources with diverse optoelectronic applications. Research focusing on semi-transparent OPVs has gained prominence in the field of energy conversion. In this study, we investigated semi-transparent OPVs utilizing PC₇₁BM and PC₆₁BM as third-component materials. The addition of PC₇₁BM improved the open-circuit voltage (V_OC) and fill factor (FF) of the devices. As a result, we selected the PM6/Y6:PC₇₁BM ternary active layer and designed two distinct semi-transparent device structures. By adopting a sequential deposition approach (pseudo-bilayer), we achieved independent control over the PM6 layer thickness, enhancing visible transmittance performance. Compared to traditional bulk heterojunction (BHJ) structures, our design exhibited superior transparency, achieving an 11.66 % power conversion efficiency (PCE) and 24.95 % maximum average visible transmittance (AVT) under optimal conditions. It is noted that our devices demonstrated exceptional photon utilization efficiency up to 2.90 %. This study significantly advances the optimization of semi-transparent OSC performance and offers new insights for developing more efficient and transparent optoelectronic devices in the future.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"138 ","pages":"Article 107174"},"PeriodicalIF":2.7,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143156564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High triplet hexahydroacridine derivatives as a host prevent exciton diffusion to adjacent layers in solution processed OLEDs","authors":"Mageshwari Anandan ,&nbsp;Stepan Kment ,&nbsp;Radek Zboril ,&nbsp;Sergii Kalytchuk ,&nbsp;Giedrius Janusas ,&nbsp;Praveen B. Managutti ,&nbsp;Sharmarke Mohamed ,&nbsp;Roghaiyeh Mazloumihaghghi ,&nbsp;Mozhgan Hosseinnezhad ,&nbsp;Jean Michel Nunzi ,&nbsp;Venkatramaiah Nutalapati ,&nbsp;Sohrab Nasiri","doi":"10.1016/j.orgel.2024.107162","DOIUrl":"10.1016/j.orgel.2024.107162","url":null,"abstract":"<div><div>One important key to improve OLEDs technology is the development and synthesis of high triplet energy host materials, which play a crucial role in improving the efficiency and lifetime. The present approach shows that it is possible to control the properties of the host materials by carefully selecting the units. Therefore, a hexahydroacridine derivative was chosen to increase the E_T value due to lower conjugation. In this study, three hosts with high triplet energy (&gt;3 eV) were designed and investigated based on hexahydroacridine (ACD) as a constant unit and branches of triphenylamine (TPA), pyrene and pyridine derivatives as different groups. Density functional theory (DFT) calculations showed the agreement of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) values with the experimental results, with the highest HOMO from DFT calculation at 5.95 eV and cyclic voltammetry (CV) at 6.09 eV for the ACD-PYRIDINE. The photophysical properties were fully discussed and revealed the fluorescence mechanism of the hosts, so that with the addition of 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-N3, N3, N6, N6-tetraphenyl-9H-carbazole-3,6-diamine (DACT-II), thermally activated delayed fluorescence (TADF) was achieved in the emitter layer with different concentrations of the hosts of 50, 70 and 90 wt%. The promising synthesized hosts were used for the fabrication of green TADF OLEDs. The fabricated OLED based on 90 % wt. ACD-TPA had CIE coordinates X = 0.26385 and Y = 0.55236, with turn on voltage 3.5 V, as well as current efficiency (CE), power efficiency (PE) and external quantum efficiency (EQE) of 40 cd A⁻¹, 26 lm.W⁻¹ and 13 %, respectively. Furthermore, the extracted brightness (52508 cd m⁻²) exceeded the values from previous studies based on acridine as an emitter layer in doped OLEDs.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"136 ","pages":"Article 107162"},"PeriodicalIF":2.7,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Naphthalene-Arylamine starburst architectures: Novel hole transport materials for enhanced OLED performance","authors":"Jinxin Miao ,&nbsp;Zhiyuan Chen ,&nbsp;Peng Xu ,&nbsp;Xudong Cao ,&nbsp;Kai Xu ,&nbsp;Senqiang Zhu ,&nbsp;Rui Liu ,&nbsp;Chong Li ,&nbsp;Guangliang Song","doi":"10.1016/j.orgel.2024.107160","DOIUrl":"10.1016/j.orgel.2024.107160","url":null,"abstract":"<div><div>The excellent hole transfer material (HTM) is beneficial to improve the stability of the device, reduce turn-on voltage(V_on) and make full use of the potential performance of the developed emissive materials. In this work, we designed and synthesized four HTMs with triarylamine and naphthalene compounds - <strong>SHT1- SHT4</strong>. The characteristics of these four compounds were investigated by TGA, DSC. UV–vis absorption and photoluminescence spectra. These four HTMs all exhibit excellent hole transmission capability for their high triplet energy levels (E_T), outstanding thermal property, morphological stabilities and appropriate highest occupied molecular orbital (HOMO) energy levels with emissive layer (EML). Four top-emission blue OLEDs with <strong>SHT1 - SHT4</strong> as hole transport layer (HTL) were fabricated and show good electroluminescence (EL) property. The results show that the device incorporating <strong>SHT3</strong> exhibit the best device performances with a low V_on of 2.79 V, external quantum efficiency (EQE_max) of 19.7 %, highest current efficiency (CE_max) and highest Power efficiency (PE_max) of 8.86 cd A⁻¹ and 9.05 lm/W, respectively.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"136 ","pages":"Article 107160"},"PeriodicalIF":2.7,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyclic(amino)(barrelene)carbene metal amide complexes: Synthesis and thermally activated delayed fluorescence","authors":"Charlotte Riley ,&nbsp;William Jones ,&nbsp;Nguyen Le Phuoc ,&nbsp;Mikko Linnolahti ,&nbsp;Alexander S. Romanov","doi":"10.1016/j.orgel.2024.107156","DOIUrl":"10.1016/j.orgel.2024.107156","url":null,"abstract":"<div><div>Carbene-metal-amide (CMA) complexes based on cyclic(amino)(barrelene)carbene (CABC) ligands have been prepared for both Cu(I) and Au(I) metal centres. Synthetic protocols based on the conventional and microwave heating enabled ten-fold shorter reaction times and high yields of the CMA materials. Stabilization of the lowest unoccupied molecular orbital (LUMO) effects the electronic and photophysical properties. These materials benefit from short excited state lifetimes down to 0.9 μs and photoluminescence quantum yields up to 66 %. Nonradiative processes are revealed and associated with the rotational freedom of the aryl moiety in the CABC carbene ligand. Steady-state and time-resolved photoluminescence spectroscopy was used to estimate an activation energy barrier of 83 meV between singlet and triplet charge transfer (CT) excited states. Varied temperature photoluminescence confirms that ³CT photoluminescence remains even at 18 K, with no contribution from locally excited triplet states ³LE. Molecular design rules have been enhanced to propose bright thermally activated delayed fluorescence (TADF) CMA emitters.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"137 ","pages":"Article 107156"},"PeriodicalIF":2.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interface modification based on norfloxacin for enhancing the performance of the inverted perovskite solar cells","authors":"Bo Qin ,&nbsp;Xinying Chen ,&nbsp;Xinyi Huang ,&nbsp;Zhen He ,&nbsp;Tingjun Wu ,&nbsp;Dongjie Wang ,&nbsp;Yu Huang ,&nbsp;Jiang Wang ,&nbsp;Zheling Zhang ,&nbsp;Jian Xiong ,&nbsp;Jian Zhang","doi":"10.1016/j.orgel.2024.107161","DOIUrl":"10.1016/j.orgel.2024.107161","url":null,"abstract":"<div><div>The hydrophobic organic hole transport layer, Poly[bis(4-phenyl)(2,4,6-triMethylphenyl)amine] (PTAA), in inverted perovskite solar cells leads to interfacial contact issues at the anode. These issues result in significant non-radiative recombination losses and unstable interfaces, which hinder the enhancement of both device performance and stability. In this work, we have developed a green, low-cost, solution-processable anode interfacial material called norfloxacin (NFXc) to enhance the wettability of PTAA, addressing the wettability mismatch between the hydrophobic PTAA layer and the highly polar perovskite precursor. The impact of NFXc on the physical properties of the films and devices has been systematically investigated. The results demonstrate that trap passivation, perovskite crystallinity adjustment, and improved charge transfer dynamics are achieved with this buried interface modification. With the introduction of NFXc, a power conversion efficiency of 19.46 % and a fill factor of 83.05 % were achieved based on solution-processed MAPbI₃/PCBM heterojunctions with NFXc modification. Additionally, the experiments indicated that the NFXc-modified device can maintain its initial PCE value even after 3500 h.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"136 ","pages":"Article 107161"},"PeriodicalIF":2.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel isocyanobenzene carbazole-based thermally activated delayed fluorophors towards solution-processed blue emitting OLED devices with high efficiency","authors":"Yang Xiao ,&nbsp;Tianyu Huang ,&nbsp;Guimin Zhao ,&nbsp;Wei Jiang ,&nbsp;Dongdong Zhang ,&nbsp;Lian Duan","doi":"10.1016/j.orgel.2024.107155","DOIUrl":"10.1016/j.orgel.2024.107155","url":null,"abstract":"<div><div>Achieving efficient blue emission is an exigent challenge for the application of thermally activated delayed fluorescent organic light-emitting diodes (TADF-OLEDs). Carbazole benzonitrile-based TADF molecules exhibit promising performance in achieving the goal. Here, by replacing the cyano group in the sensitizer with the isocyano group, a 9 nm hypochromatic shift in photoluminescence spectra of the sensitizer and an enhanced efficiency of the Förster energy transfer (FET) in TADF-sensitized fluorescence (TSF) is found. By using the isocyano-based compounds as sensitizers, a maximum external quantum efficiency of 24.5 % is obtained in solution-processed OLEDs, surpassing the cyano-based counterparts with similar structures. Moreover, the full width at half maximum (FWHM) of the emitter in the electroluminescence spectrum is also decreased from 47 nm to 38 nm, indicating a more complete energy transfer.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"137 ","pages":"Article 107155"},"PeriodicalIF":2.7,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multifunctional thermally activated delayed fluorescence emitter for both doped and non-doped organic light emitting diodes","authors":"Nisha Yadav,&nbsp;Pachaiyappan Rajamalli","doi":"10.1016/j.orgel.2024.107157","DOIUrl":"10.1016/j.orgel.2024.107157","url":null,"abstract":"<div><div>Developing efficient smart materials that display mechanochromic luminescence (MCL) and thermally activated delayed fluorescence (TADF) remains a formidable challenge. Herein, we designed and synthesized a multifunctional emitter, 2BPy-<em>m</em>TC, where benzoyl pyridyl (2BPy) acts as an acceptor and 3,6-di-<em>tert</em>-butyl-9<em>H</em>-carbazole (TC) acts as a donor. 2BPy-<em>m</em>TC exhibits blue emission with <em>λ</em>_<em>max</em> of 456 nm in pristine form and emission shifted to green with <em>λ</em>_<em>max</em> of 495 nm upon grinding. Interestingly, when fumed with CH₂Cl₂, the emission reverts to deep blue at <em>λ</em>_<em>max</em> of 440 nm. 2BPy-<em>m</em>TC possesses a <em>ΔE</em>_<em>ST</em> of 0.20 eV in neat film and 0.11 eV in doped film (5 wt% 2BPy-<em>m</em>TC: <em>m</em>CBP) and exhibits a PLQY of 42 % in neat film and 59 % in doped film. The transient photoluminescence (PL) decay curves show a delayed lifetime of 110.3 μs for the neat film and 192.9 μs for the doped film and confirm the TADF property in both doped and non-doped film. It shows an <em>EQE</em>_<em>max</em> of 16.3 % in doped device with an emission maximum of 484 nm. Conversely, it retains the <em>EQE</em>_<em>max</em> of 13.8 % in non-doped device with a slight red shift in the emission maximum (496 nm). This discovery opens a new avenue for designing multifunctional emitters with improved EL performance.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"136 ","pages":"Article 107157"},"PeriodicalIF":2.7,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent progress in high-performance thermally activated delayed fluorescence exciplexes based on multiple reverse intersystem crossing channels","authors":"Huitian Du ,&nbsp;Yaming Hao ,&nbsp;Xijian Zhang ,&nbsp;Shuyuan Zhang ,&nbsp;Qiang Liu ,&nbsp;Zhiyong Pang","doi":"10.1016/j.orgel.2024.107159","DOIUrl":"10.1016/j.orgel.2024.107159","url":null,"abstract":"<div><div>In the field of organic light-emitting diodes (OLEDs), exciplex materials with thermally activated delayed fluorescence (TADF) characteristics have garnered significant attention in recent years owing to their potential for high fluorescence efficiency, primarily achieved through the reverse intersystem crossing (RISC) process. By converting non-radiative triplet states to radiative singlet states, the RISC process can effectively regulate exciton behavior, resulting in the harvest of triplet excitons and the improvement of luminescence efficiency. Recently, multi-RISC strategies have been developed to further enhance the performance of TADF exciplex materials and devices. In this paper, we review these research progress in this area. We classify molecular design strategies according to the composition of exciplexes, discuss the design principles and energy-harvesting mechanism of high-performance TADF exciplexes based on multi-RISC strategies, and prospect their further research and development. The progressive endeavors summarized in this review may inspire further research on material design and device fabrication, and promote the development of OLED applications.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"136 ","pages":"Article 107159"},"PeriodicalIF":2.7,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing the emissive film quality: A new role of TADF materials for high-performance blue perovskite light-emitting diodes","authors":"Dengduan Zheng ,&nbsp;Yubu Zhou ,&nbsp;Yi Dai ,&nbsp;Lingjiao Zhang ,&nbsp;Qiuyu Long ,&nbsp;Baiquan Liu","doi":"10.1016/j.orgel.2024.107158","DOIUrl":"10.1016/j.orgel.2024.107158","url":null,"abstract":"<div><div>Thermally activated delayed fluorescence (TADF) materials are widely used in the field of organic light-emitting diodes (OLEDs) because they can capture both singlet and triplet excitons for light emission. However, only scare attention has been paid to the application of TADF materials in perovskite LEDs (PeLEDs) and the understanding of effects of TADF materials in PeLEDs is limited. In this study, a new role of TADF materials for achieving high-quality perovskite films to enhance the performance of PeLEDs is emphasized. TADF materials are introduced into quasi-2D blue PeLEDs to assist in the crystallization of perovskites during film annealing and ensure the formation of high-quality films with reduced defects, enhancing device performance. Additionally, a step-like hole transport layer has been constructed to reduce the hole transport barrier, which can further enhance the performance of PeLEDs. The resultant blue PeLEDs exhibits an external quantum efficiency of 5.44 %, which is 12.7-fold higher than that of the control device. Furthermore, a turn-on voltage of 2.6 V is achieved, which is the lowest for TADF-based blue PeLEDs. The findings may not only unlock a new role of TADF materials in blue PeLEDs, but also provide an alternative pathway to achieve high-performance PeLEDs.</div></div>","PeriodicalId":399,"journal":{"name":"Organic Electronics","volume":"136 ","pages":"Article 107158"},"PeriodicalIF":2.7,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}