- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Small molecule donor based on alkoxylated benzothiadiazole unit: Synthesis and photovoltaics properties
摘要： Two small molecule donors (namely BTRO and BTCN) based on the benzothiadiazole unit were synthesized in this study. In comparison to BTRO, BTCN has a narrower absorption spectrum, however, BTCN has better crystallinity, higher carrier mobility, and better light absorption that is complementary to IDIC-4F. Non-fullerene all small molecule organic solar cells (SM-OSCs) based on BTCN: IDIC-4F exhibited a power conversion efficiency (PCE) of 4.62% with short circuit current density (Jsc) of 11.46 mA/cm2, open-circuit voltage (Voc) of 0.89 V, and fill factor (FF) of 0.45. In contrast, non-fullerene SM-OSCs based on BTRO: IDIC-4F showed PCE, Jsc, Voc, and FF values of 4.08%, 11.04 mA/cm2, 0.91 V, and 0.41, respectively. Our results show that benzothiadiazole is a very good acceptor unit for regulating the absorption and energy levels of non-fullerene SM-OSCs.
关键词： benzothiadiazole,all small molecule organic solar cells,non-fullerene,small molecule donor
更新于2025-09-19 17:13:59
-
Designing alkoxy-induced based high performance near infrared sensitive small molecule acceptors for organic solar cells
摘要： Scientist are dedicated to design and synthesize efficient photovoltaic materials to overcome the energy crises. In this regard, herein, we have designed four new small acceptor molecules namely (A1, A2, A3 and A4) for better performance in organic solar cells. These molecules consist Alkoxy-Induced Naphtho-dithiophene core unit flanked with 2,2-ethylidene-5,6-dicyano-3-oxo-2,3-dihydroinden-1-ylidene-malononitrile (A1), methyl-2-cyano-2,2-ethylidene-5,6-difluoro-3-oxo-2,3-dihydroinden-1-ylidene-acetate (A2), 5,2-ethylidene-5,6-difluoro-3-oxo-2,3-dihydroinden-1-ylidene-3-methyl-2-thioxothiazolidin-4-one (A3) and 2,5-ethylidene-6-oxo-5,6-dihydrocyclopenta-thiophen-4-ylidene-malononitrile (A4) end-capped acceptor groups. Their optical, electrical and geometries have been compared with reported molecule R. Frontier molecular orbital diagram reveal excellent charge transfer rate, The electron density is shifted from donor to acceptor unit. Among all, A1 exhibits the highest absorption in the visible region (λmax) at 798 nm in chloroform solvent. The maximum open circuit voltage (2.08 V) is observed for A3 when blended with PTB7-Th donor polymer. All studied molecules have high charge mobilities due to lower reorganization energy values with respect to model molecule R. A1 has the highest electron mobility among all molecules due to lower value of reorganization energy which is 0.0034. Furthermore, all designed molecules show good Solubilities in organic solvent. A2 exhibit high value of dipole moment which reveal good solubilities in fabrication process.
关键词： Transition density matrix,Non-fullerene acceptor,Open circuit voltages,Naphtho-dithiophene,Reorganization energy,Fused ring electron acceptor
更新于2025-09-19 17:13:59
-
High-Efficiency Nonfullerene Organic Solar Cells Enabled by 1000 nm Thick Active Layers with a Low Trap-State Density
摘要： The high-efficient organic solar cells (OSCs) with thicker active layers are potential candidates for large-area solar panels fabrication. The low charge carrier mobility of the photoactive materials has been identified as the major problem hindering photovoltaic performance of the thick-film OSCs. In this study, high performance of ultra-thick film organic solar cells employing a non-fullerene acceptor BTP-4Cl and a polymer donor PBDB-TF is demonstrated. Two blends (PBDB-TF:BTP-4Cl and PBDB-TF:IT-4F) show comparable mobilities and excellent photovoltaic characteristics in thin-film devices; while in the 1000-nm-thick devices, although they both exhibit desirable and balanced mobilities, the PBDB-TF:BTP-4Cl-based blend possesses lower trap-state density than the IT-4F-based counterpart, leading to lower trap-assist recombination, longer carrier lifetime, and thus a much higher short circuit current density in the device. As a result, the BTP-4Cl-based 1000-nm-thick OSC achieves a remarkable PCE of 12.1%, which greatly outperforms the IT-4F-based devices (4.72%). What is more, for a 1000-nm thick device with active area of 4 cm2, a promising efficiency of 10.1% was obtained, showing its great potential in future large-scale production.
关键词： trap-state density,ultra-thick active layers,high efficiency,non-fullerene organic solar cells,charge carrier mobility
更新于2025-09-19 17:13:59
-
Solar-Powered Artificial Photosynthesis Coupled with Organic Synthesis
摘要： Organic photovoltaics (OPVs) have attracted much attention because of the advantages in low-cost and large-area fabrication and the great potentials in achieving flexible and semi-transparent devices. However, compared with inorganic and perovskite solar cells, OPVs show relatively low photoelectric conversion efficiencies, which is admittedly attributed to intrinsically low dielectric constants of organic materials resulting in large energy losses. With the rapid development of fused-ring electron acceptors especially with an acceptor (A)-donor (D)-acceptor (A) arrangement, PCEs of OPV devices quickly surpassed 12% and even reached 16% in a very short period, in quite a few of which the Elosss are less than 0.6 eV. Although it is common for inorganic or perovskite solar cells, high-performance OPVs with the Elosss less than 0.5 eV are quite rare up to date, which means that the Eloss is still the key factor that limits the photovoltaic efficiency of the OPV technique. Nonetheless, progresses in the development of efficient OPVs by reducing the Eloss to less than 0.5 eV have been made in the past few years.
关键词： Photovoltaic efficiency,Energy loss,Organic solar cells,Non-fullerene acceptors
更新于2025-09-19 17:13:59
-
On the absence of triplet exciton loss pathways in non-fullerene acceptor based organic solar cells
摘要： We investigate the viability of highly efficient organic solar cells (OSCs) based on non-fullerene acceptors (NFA) by taking into consideration efficiency loss channels and stability issues caused by triplet excitons (TE) formation. OSCs based on a blend of the conjugated donor polymer PBDB-T and ITIC as acceptor were fabricated and investigated with electrical, optical and spin-sensitive methods. The spin-Hamiltonian parameters of molecular TEs and charge transfer TEs in ITIC e.g., zero-field splitting and charge distribution, were calculated by Density Functional Theory (DFT) modelling. In addition, the energetic model describing the photophysical processes in the donor-acceptor blend was derived. Spin-sensitive photoluminescence measurements prove the formation of charge transfer (CT) states in the blend and the formation of TEs in the pure materials and the blend. However, no molecular TE signal is observed in the completed devices under working conditions by spin-sensitive electrical measurements. The absence of a molecular triplet state population allows to eliminate a charge carrier loss channel and irreversible photooxidation facilitated by long-lived triplet states. These results correlate well with the high power conversion efficiency of the PBDB-T:ITIC-based OSCs and their high stability.
关键词： triplet excitons,Density Functional Theory,organic solar cells,non-fullerene acceptors,photoluminescence detected magnetic resonance,electrically detected magnetic resonance
更新于2025-09-19 17:13:59
-
Achieving Optimal Bulk Heterojunction in All-Polymer Solar Cells by Sequential Processing with Nonorthogonal Solvents
摘要： Developing efficient all-polymer solar cells (all-PSCs) has always been a long-standing challenge due to the unfavorable morphology caused by conventional blend-casting (BC). Here we first employ the methodology of sequential processing (SP) with nonorthogonal solvents to fabricate facilely all-PSCs. A highly crystalline polymer donor PBDB-T is used to construct a well-organized underlying film, while a new polymer FPDI-BT1 is selected as the acceptor to be intercalated into the amorphous or semicrystalline regions of PBDB-T during the secondary deposition. By tuning the solvent composition for FPDI-BT1 processing, a bulk heterojunction-like configuration, rather than a traditional bilayer device, is obtained facilely without the need of further processing treatment. The extremely boosted power conversion efficiency of 7.15% from SP device is achieved, which is more than twice as efficient as the BC analogue (3.57%). The results demonstrate that SP is a promising strategy to fabricate high-performance all-PSCs with tunable configurations of active layers.
关键词： perylene diimide,non-fullerene acceptor,sequential processing,all-polymer solar cells,morphological control
更新于2025-09-19 17:13:59
-
Improving Performance of Non-fullerene Organic Solar Cells over 13% by Employing Silver Nanowires Doped PEDOT:PSS Composite Interface
摘要： Ag NWs/PEDOT:PSS composite was prepared by a facile solution-processing method, and was employed as anode interface in non-fullerene organic solar cells (OSCs). With the presence of Ag NWs (5%, v/v%)/PEDOT:PSS interfacial layer, a high power conversion efficiency (PCE) up to 13.53% was achieved based on PBDB-T-2Cl:IT-4F photoactive layer system, much higher than the efficiency of the controlled counterpart device with pristine PEDOT:PSS as anode modifier. Simultaneous enhancements in short-circuit current and fill factor were observed, in comparison to the case of pristine PEDOT:PSS interface, due to the improved electrical conductivity of Ag NWs/PEDOT:PSS composites accompanied by the increased work function for a better matching with ITO counter electrode, which facilitated the increased charge transmission, and the reduced charge recombination at the anode/photoactive interface for the improved device performance. The results clearly revealed that Ag NWs/PEDOT:PSS composite interface is beneficial to improve the charge extraction and in favor of realizing highly efficient non-fullerene OSCs.
关键词： composite interface,electrical conductivity,Ag nanowires,recombination,Non-fullerene organic solar cells
更新于2025-09-19 17:13:59
-
Interface-enhanced organic solar cells with extrapolated T80 lifetimes of over 20 years
摘要： With recent advances in the power conversion efficiency (PCE) of organic solar cells (OSCs) based on novel donor and non-fullerene acceptor (NFAs), improving the stability of these systems has become the most important issue for their practical applications. Herein, an efficient and highly stable OSC, containing a novel polymer donor and a non-fullerene acceptor system, is reported. The OSC is based on an inverted device structure that utilizes a self-assembled fullerene monolayer (C60-SAM) as the cathode modification layer, an efficient and highly stable OSC composes of a polymer donor of poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b’]dithiophene-alt-3-fluorothie-n o[3,4-b]thiophene-2-carboxylate] (PTB7-Th) and a non-fullerene acceptor of (2,2'-((2Z,2'Z)-(((4,4,9,9-Tetrakis(4-hexylphenyl)-4,9-dihydro-sindaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(4-((2ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-diflu oro-3-oxo-2,3-dihydro-1H-indene -2,1-diylidene))dimalononitrile) (IEICO-4F) is presented, showing a PCE of 10%. It further achieves an extrapolated T80 lifetime (the time required to reach 80% of initial performance) of 34,000 h, operating under one sun illumination equivalent. Based on an estimated solar irradiance of 1500 kWh/(m2 year) for China, a potential lifetime of 22 years is inferred for the OSC. Further investigation reveals that the reported C60-SAM modification stabilizes the OSC active layer morphology by lowering the surface energy of the underlying ZnO electron transport layer and suppressing trap-assisted recombination, thereby improving photostability. The results of this work establish important guidelines for the development of non-fullerene based OSCs with enhanced stability and pave the way for the commercialization of OSC technology.
关键词： interlayer modification,non-fullerene acceptor,photostability,green solvent,organic solar cell
更新于2025-09-19 17:13:59
-
Efficient organic solar cells based on a new a??Y-seriesa?? non-fullerene acceptor with an asymmetric electron-deficient-core
摘要： Herein, a new “Y-series” non-fullerene acceptor, Y21, bearing an asymmetric electron-deficient-core (DA’D) and fluorinated dicyanomethylene derivatives as flanking groups, was designed and synthesized for organic solar cell applications. Rather than being perfectly C2 symmetric manner of the traditional “Y-series” acceptor, Y21 possesses an electron-withdrawing unit (A’) shifted from the center of DA’D, turning into an asymmetric molecular geometry. Photovoltaic devices based on PM6:Y21 can realize a high Jsc of 24.9 mA cm-2, and a PCE of 15.4 %. Our work demonstrates a new way to tune the photoelectronic property of the “Y-series” NFAs.
关键词： non-fullerene acceptor,Y-series,asymmetric electron-deficient-core,organic solar cells,photovoltaic performance
更新于2025-09-19 17:13:59
-
Panchromatic organic photodetectors with SubPc as a non-fullerene acceptor
摘要： Panchromatic organic photodetectors are demonstrated with a lead phthalocyanine (PbPc)/boron subphthalocyanine (SubPc) planar heterojunction, where PbPc and SubPc acted as the donor and non-fullerene acceptor, respectively. Primary absorption bands of PbPc locate in ultraviolet (UV) and near-infrared (NIR) regions, while it is visible region for SubPc. As a result, the optimized device shows a wide response covered the wavelengths from UV to NIR with an external quantum ef?ciency of 10.9% at about 590 nm, which is attributed to the simultaneous dissociation of the photogenerated excitons in both PbPc and SubPc. Besides, the device also exhibits a detectivity higher than 1010 Jones in the wavelength ranged from 350 to 950 nm.
关键词： panchromatic photodetector,near-infrared,non-fullerene acceptor
更新于2025-09-19 17:13:59