J. Mater. Chem. C, 2020, 8,3374-3379 DOI: 10.1039/C9TC05763C, Paper
Cheng Wang, Lin Ma, Deqiang Guo, Xin Zhao, Zilin Zhou, Dabin Lin, Fangteng Zhang, Weiren Zhao, Jiahua Zhang, Zhaogang Nie Carrier lifetime in flexible CH3NH3PbI3 films increases with increasing tensile strain, and conversely decreases with increasing compressive strain. The content of this RSS Feed (c) The Royal Society of Chemistry
J. Mater. Chem. C, 2020, 8,3217-3225 DOI: 10.1039/C9TC06293A, Paper
Chengbo Li, Aili Wang, Lisha Xie, Xiaoyu Deng, Kejun Liao, Jin-an Yang, Yong Xiang, Feng Hao Alcohol post treatment was established for the secondary lateral grain growth of MAPbI3 perovskite films. The content of this RSS Feed (c) The Royal Society of Chemistry
Nanoscale, 2020, 12,3646-3656 DOI: 10.1039/C9NR10691J, Communication
Jiabin Qi, Hao Xiong, Chengyi Hou, Qinghong Zhang, Yaogang Li, Hongzhi Wang Stretchable and water-resistant textile-compatible photovoltaics add power-generation functionality to clothing, opening a new avenue for applications in wearable electronics. The content of this RSS Feed (c) The Royal Society of Chemistry
by Shaobing Xiong,
Jingnan Song,
Jianming Yang,
Jinqiu Xu,
Ming Zhang,
Ruru Ma,
Danqin Li,
Xianjie Liu,
Feng Liu,
Chungang Duan,
Mats Fahlman,
Qinye Bao
A new strategy using an abundant and colorful organic dye as the additive to passivate defect states and to produce more n‐type perovskite film is proposed, which remarkably enhances both efficiency and humidity/thermal stability of the perovskite solar cells.
Perovskite solar cells are a highly competitive candidate for next‐generation photovoltaic technology. Defects in the perovskite grain boundaries and on the film surfaces however have significant impacts on both the device efficiency and environmental stability. Herein, a strategy using organic dyes as additives to passivate the defect states and produce more n‐type perovskite films, thereby improving charge transport and decreasing charge recombination, is reported. Based on this strategy, the power conversion efficiency of the perovskite solar cell is significantly increased from 18.13% to 20.18% with a negligible hysteresis. Furthermore, the rich hydrogen bonds and carbonyl structures in the organic dye can significantly enhance device stability both in terms of humidity and thermal stress. The results present a promising pathway using abundant and colorful organic dyes as additives to achieve high‐performance perovskite solar cells.
J. Mater. Chem. A, 2020, 8,3872-3881 DOI: 10.1039/C9TA12188A, Paper
Bairu Li, Jieming Zhen, Yangyang Wan, Xunyong Lei, Lingbo Jia, Xiaojun Wu, Hualing Zeng, Muqing Chen, Guan-Wu Wang, Shangfeng Yang Three pyridine-functionalized fullerene derivatives with variable nitrogen sites were synthesized and used as electron transport layers of iPSCs, exhibiting tunable interactions with the perovskite layer and different electron transport properties. The content of this RSS Feed (c) The Royal Society of Chemistry
J. Mater. Chem. A, 2020, 8,3676-3685 DOI: 10.1039/C9TA13293G, Paper
Yuan Chang, Tsz-Ki Lau, Philip C. Y. Chow, Ningning Wu, Dan Su, Weichao Zhang, Huifeng Meng, Chao Ma, Tao Liu, Kun Li, Xinhui Zou, Kam Sing Wong, Xinhui Lu, He Yan, Chuanlang Zhan A ternary material system featuring two donor polymers with identical absorption spectra and differently-oriented side-chains was used in an organic photovoltaic (OPV) cell. It is the first ternary blended OPV cell with two donor polymers with >16% efficiency. The content of this RSS Feed (c) The Royal Society of Chemistry
J. Mater. Chem. A, 2020, 8,3357-3368 DOI: 10.1039/C9TA13528F, Paper
Neetesh Kumar, Hock Beng Lee, Sunbin Hwang, Jae-Wook Kang A large-scale (64 cm2), spray-coated nickel oxide (NiO) film as a hole-transport layer has successfully yielded >17% efficiency in planar triple-cation perovskite solar cells (PSCs). The content of this RSS Feed (c) The Royal Society of Chemistry
Energy Environ. Sci., 2020, 13,685-743 DOI: 10.1039/C9EE03046H, Review Article
Seyyed Alireza Hashemi, Seeram Ramakrishna, Armin Gerhard Aberle Photovoltaic devices have become ideal alternatives instead of common energy sources owing to their superior mechanical robustness and excellent power conversion efficiency that can be used for supplying wearable electronic devices. The content of this RSS Feed (c) The Royal Society of Chemistry
Author(s): Julie Dréon, Quentin Jeangros, Jean Cattin, Jan Haschke, Luca Antognini, Christophe Ballif, Mathieu Boccard
Abstract
Interest in silicon heterojunction solar cells is growing due to their manufacturing simplicity and record efficiencies. However, a significant limitation of these devices still stems from parasitic light absorption in the amorphous silicon layers. This can be mitigated by replacing the traditional (p) and (n) doped amorphous silicon selective layers by other materials. While promising results have been achieved using molybdenum oxide (MoOx) as a front-side hole-selective layer, charge transport mechanisms in that contact stack have remained elusive and device efficiencies below predictions. We carefully analyze the influence of the MoOx and intrinsic a-Si:H thicknesses on current-voltage properties and discuss transport and performance-loss mechanisms. In particular, we find that thinning down the MoOx and (i)a-Si:H layers (down to 4 nm and 6 nm respectively) mitigates parasitic sub-bandgap MoOx optical absorption and drastically enhances charge transport, while still providing excellent passivation and selectivity. High-resolution transmission microscopy reveals that such thin MoOx layer remains continuous and, while slightly sub-stoechiometric, exhibits a chemistry close to MoO3. A screen-printed device reaching a certified efficiency of 23.5% and a fill factor of 81.8% is demonstrated, bridging the gap with traditional Si-based contacts and demonstrating that dopant-free selective contacts can rival traditional approaches.
Publication date: Available online 18 January 2020
Source: Nano Energy
Author(s): Congcong Wu, Kai Wang, Munkhbayar Batmunkh, Abdulaziz S.R. Bati, Dong Yang, Yuanyuan Jiang, Yuchen Hou, Joseph G. Shapter, Shashank Priya
Abstract
Next generation photovoltaics such as dye sensitized solar cells, perovskite solar cells and organic solar cells, generally referred to as the “third-generation photovoltaic technologies”, will have a great impact on the global deployment of photovoltaic technology. Generally, these photovoltaic cells are layered-structure devices, consisting of nanostructured layers with multiple functionalities comprising of charge collection, extraction and photoconversion. Nanostructured layers including anode/cathode buffer layers, interfacial modification layers, and photon active layers are synthesized by various physical and chemical deposition techniques, which are discussed in this paper. Due to multiple coupling effects in these nanostructured materials as discussed here, the layered cells have great potential for enhanced photovoltaic efficiency. Advanced nanotechnology fabrication approaches have accelerated the design and development of novel nanostructured materials, which is driving the advancements in solar cell performance. The nanomaterials and nanostructures critically impact the optical and electronic properties of the functional layers by modulating their morphology, microstructure, and surface states; thereby influencing the output voltage and conversion efficiency. In this review, we provide a detailed discussion on recent developments in nanostructured materials and illustrate the designs for their integration with “third-generation photovoltaic technologies”. A comprehensive discussion is provided on the role of nanostructures, functionalities, and effectiveness of various nanomaterials in improving the performance of dye sensitized solar cells, perovskite solar cells and organic solar cells. Throughout the review, discussions are included on addressing the remaining challenges and research opportunities.
Graphical abstract
Third-generation PV technologies along with multiple nanomaterials and nanostructures.
J. Mater. Chem. A, 2020, 8,2962-2968 DOI: 10.1039/C9TA11989B, Communication
Chi Huey Ng, Kengo Hamada, Gaurav Kapil, Muhammad Akmal Kamarudin, Zhen Wang, Satoshi likubo, Qing Shen, Kenji Yoshino, Takashi Minemoto, Shuzi Hayase The incorporation of the GeI2 additive in novel quasi-2D/3D Sn perovskites suppresses Sn2+ oxidation and trap densities, thus enhancing the carrier dynamics of the perovskite materials. The content of this RSS Feed (c) The Royal Society of Chemistry
J. Mater. Chem. A, 2020, 8,3211-3221 DOI: 10.1039/C9TA12046G, Paper
Zhiyong Liu, Ning Wang Inverted structure ternary polymer solar cells (PSCs) are designed by blending J61 and PffBTT2-DPPT2 as the donor and Y6 as the acceptor. The content of this RSS Feed (c) The Royal Society of Chemistry
Energy Environ. Sci., 2020, 13,601-615 DOI: 10.1039/C9EE03791H, Paper
Haoyuan Li, Gjergji Sini, Joseph Sit, Adam J. Moulé, Jean-Luc Bredas Simulation of the microscopic processes in the active layers of organic photovoltaic devices directly from experimental film morphologies. The content of this RSS Feed (c) The Royal Society of Chemistry
Energy Environ. Sci., 2020, 13,635-645 DOI: 10.1039/C9EE03710A, Paper
Lingling Zhan, Shuixing Li, Tsz-Ki Lau, Yong Cui, Xinhui Lu, Minmin Shi, Chang-Zhi Li, Hanying Li, Jianhui Hou, Hongzheng Chen An alloy-like model based on Y6 and its derivative BTP-M is constructed to fabricate ternary organic solar cells, leading to a best efficiency of 17.03%. The content of this RSS Feed (c) The Royal Society of Chemistry
by Gyu Min Kim,
Ayumi Ishii,
Senol Öz,
Tsutomu Miyasaka
The significant improvement of photovoltaic performances by synergetic effects of GeI2 and methylammonium chloride (MACl) is described. The improved solubility of GeI2 with the help of MACl in the precursor leads to high performance perovskite solar cells.
Abstract
Interfacial engineering, grain boundary, and surface passivation in organic–inorganic hybrid perovskite solar cells (HyPSCs) are effective in achieving high performance and enhanced durability. Organic additives and inorganic doping are generally used to chemically modify the surface contacting charge transport layers, and/or grain boundaries so as to reduce the defect density. Here, a simple but tricky one‐step method to dope organic–inorganic hybrid perovskite with Ge for the first time is reported. Unlike Ge doping to all‐inorganic perovskites, application of GeI2 in organic–inorganic perovskite precursors is challenging due to the extremely poor solubility of GeI2 in hybrid perovskite ink, leading to failure in the formation of uniform films. However, it is found that addition of methylammonium chloride (MACl) into the precursor remarkably increases the solubility of GeI2. This MACl‐assisted Ge doping of hybrid perovskites produces high‐quality crystalline film with its surface passivated with nonvolatile GeI2 (GeO2) and the volatile MACl additive also improves the uniformity of GeO2 distribution in the perovskite films. The resulting Ge‐doped mixed cation and mixed halide perovskite films with composition FA0.83MA0.17Ge0.03Pb0.97(I0.9Br0.1)3 show superior photoluminescence lifetime, power conversion efficiency above 22%, and greater stability toward illumination and humidity, outperforming photovoltaic properties of HyPSCs prepared without the Ge doping.
by Havid Aqoma,
Imil Fadli Imran,
Muhibullah Al Mubarok,
Wisnu Tantyo Hadmojo,
Young Rag Do,
Sung‐Yeon Jang
High‐efficiency, solution‐processed, hybrid tandem photovoltaic devices are demonstrated employing colloidal quantum dot (CQD) and organic bulk heterojunction as an active layer for front‐ and back‐cell, respectively. Notable efficiency of 12.82% is achieved, which is the highest among the reported CQD‐based solar cells, including single‐junction devices and tandem devices.
Abstract
While colloidal quantum dot photovoltaic devices (CQDPVs) can achieve a power conversion efficiency (PCE) of ≈12%, their insufficient optical absorption in the near‐infrared (NIR) regime impairs efficient utilization of the full spectrum of visible light. Here, high‐efficiency, solution‐processed, hybrid series, tandem photovoltaic devices are developed featuring CQDs and organic bulk heterojunction (BHJ) photoactive materials for front‐ and back‐cells, respectively. The organic BHJ back‐cell efficiently harvests the transmitted NIR photons from the CQD front‐cell, which reinforces the photon‐to‐current conversion at 350–1000 nm wavelengths. Optimizing the short‐circuit current density balance of each sub‐cell and creating a near ideal series connection using an intermediate layer achieve a PCE (12.82%) that is superior to that of each single‐junction device (11.17% and 11.02% for the CQD and organic BHJ device, respectively). Notably, the PCE of the hybrid tandem device is the highest among the reported CQDPVs, including single‐junction devices and tandem devices. The hybrid tandem device also exhibits almost negligible degradation after air storage for 3 months. This study suggests a potential route to improve the performance of CQDPVs by proper hybridization with NIR‐absorbing photoactive materials.
by Yilin Wang,
Qinglian Zhu,
Hafiz Bilal Naveed,
Heng Zhao,
Ke Zhou,
Wei Ma
A proper vertical phase separation and purer phases of donor and acceptor are finely controlled by sequential blade‐casting strategy in the PTB7‐Th:FOIC‐based organic solar cell, resulting in simultaneous enhancement of efficiency, stability, and mechanical properties.
Abstract
As a predominant fabrication method of organic solar cells (OSCs), casting of a bulk heterojunction (BHJ) structure presents overwhelming advantages for achieving higher power conversion efficiency (PCE). However, long‐term stability and mechanical strength are significantly crucial to realize large‐area and flexible devices. Here, controlling blend film morphology is considered as an effective way toward co‐optimizing device performance, stability, and mechanical properties. A PCE of 12.27% for a P‐i‐N‐structured OSC processed by sequential blade casting (SBC) is reported. The device not only outperforms the as‐cast BHJ devices (11.01%), but also shows impressive stability and mechanical properties. The authors corroborate such enhancements with improved vertical phase separation and purer phases toward more efficient transport and collection of charges. Moreover, adaptation of SBC strategy here will result in thermodynamically favorable nanostructures toward more stable film morphology, and thus improving the stability and mechanical properties of the devices. Such co‐optimization of OSCs will pave ways toward realizing the highly efficient, large‐area, flexible devices for future endeavors.
by Nikita Drigo†, Cristina Roldan-Carmona†, Marius Franckevic?ius‡, Kun-Han Lin§, Rokas Gegevic?ius‡, Hobeom Kim†, Pascal A. Schouwink?, Albertus A. Sutanto†, Selina Olthof?, Muhammad Sohail?, Klaus Meerholz?, Vidmantas Gulbinas‡, Cle´mence Corminboeuf§, Sanghyun Paek*†, and Mohammad Khaja Nazeeruddin*†
J. Mater. Chem. C, 2020, 8,3351-3358 DOI: 10.1039/C9TC05736F, Paper
Shoulong Chen, Tianju Zhang, Xiaolin Liu, Jinli Qiao, Lin Peng, Jun Wang, Yongsheng Liu, Tieying Yang, Jia Lin A stable CsPbI2Br perovskite phase can be achieved when doped with an appropriate amount of La3+ ions. The content of this RSS Feed (c) The Royal Society of Chemistry
by Qilin Zhang,
Xin Yuan,
Yifeng Feng,
Bryon W. Larson,
Gregory M. Su,
Yin Maung Maung,
Nopporn Rujisamphan,
Youyong Li,
Jianyu Yuan,
Wanli Ma
Through time‐resolved microwave conductivity measurements, the local intrinsic free‐carrier properties in three representative organic bulk heterojunction blends are comparatively investigated, and it is believed that the results shown here are important in understanding and improving the efficiency and stability of organic solar cells.
Polymer–polymer blends have been reported to exhibit exceptional thermal and ambient stability. However, power conversion efficiencies (PCEs) from devices using polymeric acceptors have been recorded to be significantly lower than those based on conjugated molecular acceptors. Herein, two organic nonfullerene bulk heterojunction (BHJ) blends ITIC:PBDB‐T and N2200:PBDB‐T, together with their fullerene counterpart, PCBM:PBDB‐T, are adopted to understand the effect of electron acceptors on device performance. Free charge carrier properties using time‐resolved microwave conductivity (TRMC) measurements are comprehensively investigated. The nonfullerene devices show an improved PCE of 10.06% and 6.65% in the ITIC‐ and N2200‐based cells, respectively. In comparison, the PCBM:PBDB‐T‐based devices yield a PCE of 5.88%. The optimal N2200:PBDB‐T produced the highest TRMC mobility, longest lifetime, and greatest free‐carrier diffusion length. It is found that such phenomena can be associated with the unfavorable morphology of the all‐polymer BHJ microstructure. In contrast, the solar cells using either the PCBM or ITIC acceptors display a more balanced donor and acceptor phase separation, leading to more efficient free‐carrier separation and transport in the operating device. By sacrificing efficiency for superior stability, it is shown that the improved structure in all‐polymer blend can deliver a more stable morphology under thermal stress.
Herein, a planar n–i–p perovskite solar cell based on a nanocrystalline WOx electron transfer layer is developed, with a low‐temperature fabrication process (50 °C) and record high efficiency, exceeding 20%.
Low‐temperature, solution‐processed metal oxides are of great interest as alternative materials for electron transport layers in perovskite solar cells. WOx is a promising candidate that could truly enable low‐temperature (<100 °C) processing. However, its amorphous‐state form typically obtained with the solution process suffers from high defect density. This causes large charge recombination, and consequently significant deterioration of the solar cell efficiency. Herein, an ultra‐low‐temperature processed (50 °C) nanocrystalline WOx as the electron transport layer, free of this problem, is demonstrated. This material is obtained by the reaction of tungsten chloride with hexanol, which induces transformation of the precursor solution into stable colloidal particles. The best solar cell, with the WOx electron transport layer, achieved an efficiency of 20.77%, which is a record performance for this class of perovskite solar cells.
by Sang Myeon Lee,
Tanya Kumari,
Byongkyu Lee,
Yongjoon Cho,
Jungho Lee,
Jiyeon Oh,
Mingyu Jeong,
Sungwoo Jung,
Changduk Yang
Structurally different conjugation systems afford new small molecules of the SM‐axis for disparate functionality of third components in ternary organic solar cells. Systematic investigation of the SM‐axis series and host donor/acceptor materials for photoluminescence and microstructural properties reveals synergistic features of two major working models co‐existing in SM‐axis‐based ternary organic solar cells, thus achieving improved performance along variations in conjugated pathways.
Abstract
A family of the SM‐axis series based on benzo[1,2‐b:4,5‐b′]dithiophene and 3‐ethylrhodanine (RD) units with structurally different π‐conjugation systems are synthesized as a means to understand the structure–property relationship of conjugated pathways in ternary non‐fullerene organic solar cells (NF‐OSCs) as a third component. The optical and electrochemical properties of the SM‐axis are highly sensitive both to the functionalized direction and to the number of RD groups. Enhanced power conversion efficiencies (PCEs) of over 11% in ternary devices are obtained by incorporating optimal SM‐X and SM‐Y contents from PBDB‐T:ITIC binary NF‐OSCs, while a slightly lower PCE is observed with the addition of SM‐XY. The results of in‐depth studies using various characterization techniques demonstrate that working mechanisms of SM‐axis‐based ternary NF‐OSCs are distinctly different from one another: an energy‐transfer mechanism with an alloy‐like model for SM‐X, a charge transfer with the same model for SM‐Y, and an energy transfer without such a structure for SM‐XY. As extension of the scope, a SM‐X‐based ternary NF‐OSC in the PM6:IT4F system also shows a greatly enhanced PCE of over 13%. The findings provide insights into the effects of conjugated pathways of organic semiconductors on mechanisms of ternary NF‐OSCs, advancing the understanding for synthetic chemists, materials engineers, and device physicists.
