Article
Chemistry, Physical
Viktor V. Brus, Nora Schopp, Seo-Jin Ko, Joachim Vollbrecht, Jaewon Lee, Akchheta Karki, Guillermo C. Bazan, Thuc-Quyen Nguyen
Summary: The relationship between the temperature-light intensity dependence of open-circuit voltage V-oc in nonfullerene-based organic solar cells and the material characteristics and multimechanism recombination parameters was investigated. By systematically varying the effective bandgap E-g, E-eff and the electrode layers, different contributions of bimolecular, bulk, and surface trap-assisted recombination mechanisms were observed. The analytical model and voltage-impedance spectroscopy technique provide a useful tool to quantify multimechanism recombination parameters, effective density of states N-c, and energetic disorder sigma in organic solar cells under operating conditions. The proposed model's validity in understanding the temperature and light intensity dependence of V-oc was demonstrated by applying it to four different donor:nonfullerene acceptor blend systems with conventional or inverted device architectures.
ADVANCED ENERGY MATERIALS
(2021)
Review
Chemistry, Multidisciplinary
Quan Liu, Koen Vandewal
Summary: Organic solar cells benefit from non-fullerene acceptors (NFA) due to their high absorption coefficients, tunable frontier energy levels, and optical gaps, as well as their relatively high luminescence quantum efficiencies as compared to fullerenes. This review summarizes the understanding and quantification of non-radiative decay, as well as strategies for suppressing these losses, in order to guide researchers in finding future solar harvesting donor-acceptor blends with high efficiency.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Yong Jun Kim, Seong Eun Park, Byung Jin Cho
Summary: This study proposes a hybrid generator composed of an OPV module and TEG to improve power generation performance by minimizing the VOC losses of the OPV module. The hybrid device shows improved efficiency and photon absorption of the OPV module, increased VOC, and longer charge recombination lifetime, resulting in higher short-circuit current and up to 46.3% more electrical energy harvesting compared to the OPV module alone.
Article
Chemistry, Multidisciplinary
Sohyeon Kim, Jun Hyeok Jang, Ziang Wu, Mi Jung Lee, Han Young Woo, Inchan Hwang
Summary: The study investigates the correlation of n(id), PL characteristics, and V-oc in triple-cation mixed-halide perovskite depending on interfacial crystal quality. It highlights the importance of evaluating interfacial crystal quality for understanding charge recombination and device optimization.
Article
Chemistry, Multidisciplinary
Shengli Zhao, Jing Leng, Shiping Wang, Xianchang Yan, Zixi Yin, Yanfeng Yin, Jun Zhang, Shengye Jin
Summary: In this study, a modified transient reflection (TR) spectroscopy method was developed to directly observe and determine the longitudinal carrier transport process in MAPbI(3) polycrystalline thin films. By spatially separating the pump and probe beams on each side of the film, the carrier transport dynamics along the film thickness were resolved. The longitudinal carrier diffusion coefficients (D) in perovskite films with different thicknesses and grain sizes were determined, providing a reference for quick quality screening and evaluation of perovskite polycrystalline thin films.
Article
Nanoscience & Nanotechnology
Yajun Gao, Jiang Liu, Furkan H. Isikgor, Mingcong Wang, Jafar I. Khan, Stefaan De Wolf, Frederic Laquai
Summary: This study investigates the influence of interfaces on carrier dynamics in metal halide perovskite solar cells using ultrafast transient reflection spectroscopy. The results show that inserting a LiF interlayer can reduce interface-induced carrier recombination velocity and improve the open-circuit voltage of the devices, while using a passivation agent can effectively decrease the carrier recombination velocity at the surface and grain boundaries.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Yajun Gao, Jiang Liu, Furkan H. Isikgor, Mingcong Wang, Jafar Khan, Stefaan De Wolf, Frederic Laquai
Summary: In this study, the interface carrier dynamics in metal halide perovskite (MHP) solar cells were investigated using ultrafast transient reflection (TR) spectroscopy. The addition of a LiF interlayer was found to reduce the interface-induced carrier recombination velocity and improve the open-circuit voltage of the devices. Furthermore, the effect of PhenHCl passivation on the carrier recombination velocity in CsFAMA was revealed.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Yihan Zeng, Danqin Li, Zuo Xiao, Hongbo Wu, Zeng Chen, Tianyu Hao, Shaobing Xiong, Zaifei Ma, Haiming Zhu, Liming Ding, Qinye Bao
Summary: Ternary architecture shows potential in enhancing power conversion efficiencies of organic solar cells, with the fill factor generally below 78%. Studies indicate that effective exciton dissociation, enhanced charge transport, and suppressed recombination are crucial for achieving high-fill factor and low-energy loss in ternary cells.
ADVANCED ENERGY MATERIALS
(2021)
Article
Chemistry, Physical
Rafael Besse, Han Wang, Damien West, Juarez L. F. De Silva, Shengbai Zhang
Summary: Understanding the dynamics of charge transfer at vertical heterostructures of transition metal dichalcogenide monolayers is crucial for future technological applications. In this study, a different mechanism from type-II is found in the MoS2/PtSe2 van der Waals heterobilayer, where the phonon bottleneck effectively separates photoelectrons from photoholes, providing a new direction for effective charge separation at interfaces.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Kang-Ning Zhang, Xiao-Tao Hao
Summary: Organic photovoltaics (OPVs) are highly promising for outdoor and indoor applications. Recent developments in nonfullerene acceptors have significantly improved power conversion efficiencies (PCEs) of single-junction cells. However, these advancements have also led to unexpected photophysical observations, highlighting the need for further spectroscopic research.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Fenghua Zhang, Xiong Li, Yujiao Yan, Mandi Li, Tao Lin, Jun Zhou, Yaohui Zhu, Denghui Xu
Summary: Indoor organic photovoltaic technology shows promise for off-grid self-power supply in the Internet of Things industry. This study focuses on indoor organic photovoltaic devices prepared with wide bandgap polymer PM6 and fullerene derivatives PC71BM as the donor and acceptor, respectively. The device's photovoltaic performance, carrier recombination characteristics, and molecular packing were compared to devices using non-fullerene acceptor Y6. The PM6:PC71BM device demonstrates superior performance with an power conversion efficiency of 18.7% under white LED illumination, while the Y6 acceptor device only achieved 14.7%. These findings highlight the effectiveness of fullerene acceptors for high-performance organic photovoltaic devices under slim light illumination, with potential for use in indoor photovoltaic devices for the Internet of Things.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Review
Chemistry, Physical
Bin Kan, Faheem Ershad, Zhoulyu Rao, Cunjiang Yu
Summary: Organic solar cells (OSCs) have made significant progress in efficiency and cost through the evolution of organic photovoltaic materials and device engineering. Their emerging and potential usages in critical applications such as biomedical fields are on the rise.
Article
Materials Science, Multidisciplinary
Toshiharu Saito, Shin-ichiro Natsuda, Rei Shirouchi, Kenta Imakita, Kazuki Kohzuki, Yasunari Tamai
Summary: The large voltage loss is a significant disadvantage of organic solar cells (OSCs) compared with inorganic and perovskite solar cells and should be reduced to further improve the power conversion efficiency of OSCs. In this study, the voltage loss in OSCs with controlled energy difference between excited and charge transfer states is discussed. The advantages of narrow-bandgap fused-ring nonfullerene acceptors (NFAs) paired with wide-bandgap donors in terms of higher photoluminescence quantum yield and efficient charge separation with smaller voltage loss are highlighted.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Jin Wang, Le Liu, Siqi Chen, Guangliu Ran, Wenkai Zhang, Min Zhao, Chengjie Zhao, Fushen Lu, Tonggang Jiu, Yuliang Li
Summary: In this study, cyclopropylcarbamidine hydrochloride (CPAH) was demonstrated as a novel organic halide salt for constructing a 2D layer to passivate the surface of a phase-pure FAPbI3 film. The introduction of a 2D passivation layer was found to suppress charge recombination and promote charge transfer, resulting in an impressive power conversion efficiency (PCE) of 22.8% for the prepared planar devices based on 3D FAPbI(3)/2D (CPA)(2)PbI2Cl2. The devices also showed enhanced stability in wet, thermal, and light conditions.
Article
Electrochemistry
Di Zhang, Sidong Zhang, Yanyan Fang, Dongmei Xie, Xiaowen Zhou, Yuan Lin
Summary: Introducing bifunctional linkers between TiO2 electrodes and quantum dots was an effective approach for the preparation of quantum dot-sensitized solar cells. Three types of linkers were studied, with phenyl MBA-TiO2 electrodes achieving the highest Cd content and PCE. The modified TiO2 electrodes showed lower electron recombination rates and higher efficiency, demonstrating the importance of linker selection for QDSCs design and optimization.
ELECTROCHIMICA ACTA
(2021)
Article
Chemistry, Physical
Timothy J. Magnanelli, Sebastian Engmann, Jared K. Wahlstrand, John C. Stephenson, Lee J. Richter, Edwin J. Heilweil
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Article
Chemistry, Multidisciplinary
Tommaso Nicolini, Jokubas Surgailis, Achilleas Savva, Alberto D. Scaccabarozzi, Rana Nakar, Damien Thuau, Guillaume Wantz, Lee J. Richter, Olivier Dautel, Georges Hadziioannou, Natalie Stingelin
Summary: Organic mixed conductors are utilized in various applications, however, polymer-based conductors often experience significant volumetric changes during ion uptake/rejection. The new material P3HHT shows low swelling behavior and has potential for applications in bioelectronics and beyond.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Physical
Ian Pelse, Austin L. Jones, Lee J. Richter, John R. Reynolds
Summary: Control of polymer aggregation by selective introduction of backbone disorder through random copolymerization has been effective for optimizing the coating of fullerene-based bulk-heterojunction photovoltaics. A new terpolymer composition, PffBT4T(80)-co-3T(20)-2OD (80-20), shows good processability and solid-state performance when processing IDTBR blend films, achieving power conversion efficiencies approaching 9%. However, IDTBR delays polymer solidification, disrupts polymer crystallization, and compromises the overall crystallinity in the blend, leading to lower power conversion efficiencies compared to PC71BM devices.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Physical
Margherita Biondi, Min-Jae Choi, Seungjin Lee, Koen Bertens, Mingyang Wei, Ahmad R. Kirmani, Geonhui Lee, Hao Ting Kung, Lee J. Richter, Sjoerd Hoogland, Zheng-Hong Lu, F. Pelayo Garcia de Arquer, Edward H. Sargent
Summary: This study reports a strategy to reduce trap states in quantum dot solar cells by changing the solvent type, leading to higher power conversion efficiency.
ACS ENERGY LETTERS
(2021)
Article
Multidisciplinary Sciences
Subhrangsu Mukherjee, Jason K. Streit, Eliot Gann, Kumar Saurabh, Daniel F. Sunday, Adarsh Krishnamurthy, Baskar Ganapathysubramanian, Lee J. Richter, Richard A. Vaia, Dean M. DeLongchamp
Summary: In this study, polarized resonant soft X-ray scattering was used to measure local chain orientation in polystyrene grafted gold nanoparticles and quantify the thickness of the anisotropic region of the corona as well as the extent of chain orientation within it.
NATURE COMMUNICATIONS
(2021)
Article
Nanoscience & Nanotechnology
Peter J. Dudenas, Eliot Gann, Guillaume Freychet, Lee J. Richter, Dean M. DeLongchamp
Summary: The study found that using polymer-polymer blends and meniscus-guided coating to tailor semiconducting materials in printed electronics can lead to long-wavelength instabilities during coating, which directly affect the alignment of semiconducting polymer nanofibrils and the performance of electronic devices. This highlights the need to consider the potential impact of these instabilities when optimizing coating conditions.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Markus Regnat, Chang-Ki Moon, Sandra Jenatsch, Beat Ruhstaller, Kurt P. Pernstich
Summary: We studied the reduced power efficiency in a red phosphorescent OLED with an exciplex host after prolonged operation. The increase in driving voltage was found to be the sole cause for the reduction in power efficiency, while the radiant flux remained constant. By using multiple measurement methods, we were able to develop an electrical model that accurately described the driving voltage increase. Furthermore, a sensitivity analysis revealed that the trap density and mobility of the hole transporting layer had the largest impact on the driving voltage increase.
ORGANIC ELECTRONICS
(2022)
Article
Nanoscience & Nanotechnology
Lucas Q. Flagg, Lauren E. Asselta, Nicholas D'Antona, Tommaso Nicolini, Natalie Stingelin, Jonathan W. Onorato, Christine K. Luscombe, Ruipeng Li, Lee J. Richter
Summary: Organic mixed ionic electronic conductors (OMIECs) have great potential in various new technologies, but studying them in their operating state is difficult. This study presents a new approach to investigate the electrochemical switching of a prototypical OMIEC and finds that the crystalline regions are relatively hydrophobic and the potential-induced changes in crystal structure do not clearly correlate with the transistor performance.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Lidia Kuo, Vinod K. Sangwan, Sonal Rangnekar, Ting-Ching Chu, David Lam, Zhehao Zhu, Lee J. Richter, Ruipeng Li, Beata M. Szydlowska, Julia R. Downing, Benjamin J. Luijten, Lincoln J. Lauhon, Mark C. Hersam
Summary: Aerosol-jet printing technology is utilized to achieve highly responsive photodetectors with superior optoelectronic properties, surpassing previously reported devices by three orders of magnitude. Properly designed processing and ink formulations enable the processing and application of ultrathin MoS2 nanosheets, providing a new approach for scalable manufacturing in mechanically flexible optoelectronics.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Bin Sun, Amin Morteza Najarian, Laxmi Kishore Sagar, Margherita Biondi, Min-Jae Choi, Xiyan Li, Larissa Levina, Se-Woong Baek, Chao Zheng, Seungjin Lee, Ahmad R. Kirmani, Randy Sabatini, Jehad Abed, Mengxia Liu, Maral Vafaie, Peicheng Li, Lee J. Richter, Oleksandr Voznyy, Mahshid Chekini, Zheng-Hong Lu, F. Pelayo Garcia de Arquer, Edward H. Sargent
Summary: Colloidal quantum dots (CQDs) have tunable bandgap and solution processing, making them promising materials for infrared (IR) light detection. However, the time response of CQD IR photodiodes is currently inferior to that of Si and InGaAs. The high permittivity of II-VI CQDs leads to slow charge extraction, while III-Vs offer low permittivity and potential for high-speed operation. By managing the surface using amphoteric ligand coordination, the performance of InAs CQD solids is improved, achieving fast response time and high external quantum efficiency.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Jiajie Guo, Lucas Q. Flagg, Duyen K. Tran, Shinya E. Chen, Ruipeng Li, Nagesh B. Kolhe, Rajiv Giridharagopal, Samson A. Jenekhe, Lee J. Richter, David S. Ginger
Summary: In this study, the performance of ladder polymer BBL as an OECT in aqueous environment is investigated. The film swelling and structural changes during the electrochemical charge injection process are examined using various techniques. The results reveal that the BBL films undergo irreversible hydration and significant water retention, leading to a hydrophilic environment that facilitates efficient ion transport. The rigid ladder backbone of BBL maintains the crystalline order and allows the original dehydrated state to be recovered after drying.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Micah Barker, Tommaso Nicolini, Yasmina Al Yaman, Damien Thuau, Olga Siscan, Sasikumar Ramachandran, Eric Cloutet, Cyril Brochon, Lee J. Richter, Olivier J. Dautel, Georges Hadziioannou, Natalie Stingelin
Summary: A model mixed-conducting polymer blended with an amphiphilic block-copolymer shows significantly enhanced electro-chemical doping kinetics, resulting in faster electrochemical transistors with high transduction. This approach is robust, reproducible, and readily adaptable to other mixed conductors without exhaustive chemical modification.
MATERIALS HORIZONS
(2023)
Article
Materials Science, Multidisciplinary
Giovanni Maria Matrone, Elizabeth Gutierrez-Meza, Alex H. Balzer, Aditi Khirbat, Artem Levitsky, Alexander B. Sieval, Gitti. L. Frey, Lee J. Richter, Carlos Silva, Natalie Stingelin
Summary: Polymer-based blend morphology in systems like organic photovoltaics typically deviates from equilibrium, impacting final device performance. By comparing different fullerenes with a specific polymer in blends, phase diagrams can provide insights into optoelectronic processes and structure-property relationships.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Materials Science, Multidisciplinary
Sebastian Engmann, Emily G. Bittle, Lee J. Richter, Rawad K. Hallani, John E. Anthony, David J. Gundlach
Summary: Magneto electroluminescence (MEL) is used as a tool to study spin dynamics in organic light emitting diodes (OLEDs) in this study. A quantitative model for MEL is developed and applied to devices based on different emitters, revealing that structured responses are found in textured films and additional structures exist in intersections of singlet character between adjacent states. The MEL responses can be adequately described by an extended Merrifield model, providing insights into the underlying physics in OLED devices through the inclusion of charge injection.
JOURNAL OF MATERIALS CHEMISTRY C
(2021)
Article
Materials Science, Multidisciplinary
Michael C. Heiber, Andrew A. Herzing, Lee J. Richter, Dean M. DeLongchamp
JOURNAL OF MATERIALS CHEMISTRY C
(2020)
