- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Highly Efficient All-Small-Molecule Organic Solar Cells with Appropriate Active Layer Morphology by Side Chain Engineering of Donor Molecules and Thermal Annealing
摘要： It is very important to fine-tune the nanoscale morphology of donor:acceptor blend active layers for improving the photovoltaic performance of all-small-molecule organic solar cells (SM-OSCs). In this work, two new small molecule donor materials are synthesized with different substituents on their thiophene conjugated side chains, including SM1-S with alkylthio and SM1-F with fluorine and alkyl substituents, and the previously reported donor molecule SM1 with an alkyl substituent, for investigating the effect of different conjugated side chains on the molecular aggregation and the photophysical, and photovoltaic properties of the donor molecules. As a result, an SM1-F-based SM-OSC with Y6 as the acceptor, and with thermal annealing (TA) at 120 °C for 10 min, demonstrates the highest power conversion efficiency value of 14.07%, which is one of the best values for SM-OSCs reported so far. Besides, these results also reveal that different side chains of the small molecules can distinctly influence the crystallinity characteristics and aggregation features, and TA treatment can effectively fine-tune the phase separation to form suitable donor–acceptor interpenetrating networks, which is beneficial for exciton dissociation and charge transportation, leading to highly efficient photovoltaic performance.
关键词： small molecule donor materials,all-small-molecule organic solar cells,interpenetrating networks,side-chain engineering,thermal annealing
更新于2025-09-23 15:21:01
-
Modulation of donor alkyl terminal chains with shifting branching point leads to optimized morphology and efficient all-small-molecule organic solar cells
摘要： Terminal group modification is one of the most influential factors for small molecular donors compared with their polymer counterparts, resulting in an opportunity to optimize the morphology of all-small-molecule organic solar cells (ASM-OSCs). In this manuscript, we report three novel small molecular donors with branching points at the 1-, 2-, and 3-positions in alkyl terminal chains, called BSCl-C1, BSCl-C2 and BSCl-C3, respectively. Using IDIC-4Cl as acceptor, the subtle branching position shift achieves a dramatic disparity in photovoltaic parameters, as indicated by the short circuit current (Jsc) changing from 4.90 mA cm?2 to 20.1 mA cm?2 to 14.2 mA cm?2 and the fill factor varying from 33.9% to 71.3% to 67.0% for BSCl-C1, BSCl-C2, and BSCl-C3, respectively. The best device performance of 12.4% is obtained by the BSCl-C2:IDIC-4Cl system, which not only ranks among the top values reported to date, but also exhibits low energy loss in systems that use IDIC as acceptors. The notable device performance based on BSCl-C2 is attributed to the optimized phase morphology caused by the strong molecular crystallinity and suitable intermolecular interaction with IDIC-4Cl. These results demonstrate that suitably tuning the branching position of terminal groups could promote the high performance of ASM-OSCs.
关键词： branching point,phase morphology,crystallinity,intermolecular interaction,all-small-molecule
更新于2025-09-23 15:21:01
-
15.3% efficiency all-small-molecule organic solar cells enabled by symmetric phenyl substitution; ???????ˉ1?§°??§è?ˉ??o???é￥°?????°??????é??è??15.3%?????¨?°? ????-??????o?¤aé?3è????μ?±?;
摘要： Synergistic optimization of donor-acceptor blend morphologyis a hurdle in the path of realizing efficient non-fullerene small-molecule organic solar cells (NFSM-OSCs) due to the anisotropic conjugated backbones of both donor and acceptor. Therefore, developing a facile molecular design strategy to effectively regulate the crystalline properties of photoactive materials, and thus, enable the optimization of blend morphology is of vital importance. In this study, a new donor molecule B1, comprising phenyl-substituted benzo-dithiophene (BDT) central unit, exhibits strong interaction with the non-fullerene acceptor BO-4Cl in comparison with its corresponding thiophene-substituted BDT-based material, BTR. As a result, the B1 is affected and induced from an edge-on to a face-on orientation by the acceptor, while the BTR and the acceptor behave individually for the similar molecular orientation in pristine and blend films according to grazing incidence wide angle X-ray scattering results. It means the donor-acceptor blend morphology is synergistically optimized in the B1 system, and the B1:BO-4Cl-based devices achieve an outstanding power conversion efficiency (PCE) of 15.3%, further certified to be 15.1% by the National Institute of Me-trology, China. Our results demonstrate a simple and effective strategy to improve the crystalline properties of the donor molecule as well as synergistically optimize the morphology of the all-small-molecule system, leading to the high-performance NFSM-OSCs.
关键词： all-small-molecule,intermolecular interaction,crystallinity,organic solar cells,non-fullerene
更新于2025-09-23 15:19:57
-
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
-
All-Small-Molecule Organic Solar Cells with an Ordered Liquid Crystalline Donor
摘要： A new small-molecule donor, namely BTR-Cl, which possesses a strong liquid crystalline property and high crystallinity, works well with the non-liquid crystalline acceptor Y6 and gives a record-high power conversion efficiency (PCE) of 13.6% in single-junction all-small-molecule organic solar cells. The BTR-Cl:Y6-based device was certified at the National Institute of Metrology, certifying a PCE of 13.0%.
关键词： All-small-molecule organic solar cells,Phase separation,Liquid crystalline donor,Power conversion efficiency,High crystallinity
更新于2025-09-19 17:13:59
-
An all small molecule organic solar cell based on a porphyrin donor and a non-fullerene acceptor with complementary and broad absorption
摘要： A thieno[3,2-b]thiophene-functionalized porphyrin molecule (DEP-TT) with the ethynylene bridges between the diketopyrrolopyrrole and porphyrin units has been designed and synthesized as the donor material. DEP-TT exhibits a broad absorption wavelength in the visible region with the onset absorption to 898 nm of the film and a low optical band gap of 1.38 eV. IDT-C8, as the acceptor material has a relatively strong absorption spectrum ranging from 500-750 nm in the solid film, which exactly fills the absorption trough of DEP-TT. The power conversion efficiency (PCE) of all small molecule increased from 0.64% (Jsc = 2.61 mA cm-2, Voc = 0.82 V, and FF = 0.30) to 5.14% (Jsc = 11.15 mA cm-2, Voc = 0.71 V, and FF = 0.65) after solvent vapor annealing. The PCE of 5.14% provided valuable recommendation based on porphyrin all small molecule system, since few work has involved in this field.
关键词： organic solar cells,all small molecule,complementary absorption,porphyrin
更新于2025-09-16 10:30:52
-
13.34% Efficiency Nonfullerene All-Small-Molecule Organic Solar Cells Enabled by Modulating Crystallinity of Donors via a Fluorination Strategy
摘要： Nonfullerene all-small-molecule organic solar cells (NFSM-OSCs) have shown a promising potential towards the commercialization of OSCs, owing to their unique advantages of high purity, easy synthesis and good reproducibility. However, great challenges in the modulation of phase separation morphology have limited their future development. Herein, two novel small molecular donors of BTEC-1F and BTEC-2F, derived from the small molecule DCAO3TBDTT, were designed and synthesized. While using Y6 as the acceptor, the devices based on non-fluorinated DCAO3TBDTT showed an open circuit voltage (Voc) of 0.804 V and a power conversion efficiency (PCE) of 10.64%. Mono-fluorinated BTEC-1F showed an increased Voc of 0.870 V and a PCE of 11.33%. More impressively, the fill factor (FF) of di-fluorinated BTEC-2F based NFSM-OSC was largely improved to 72.35% resulting in an impressive PCE of 13.34%, which was much higher than that of BTEC-1F (61.35%) and DCAO3TBDTT (60.95%). To the best of our knowledge, this is the highest reported PCE to date for NFSM-OSCs. BTEC-2F depicted a more compact molecular stacking and a lower crystallinity as revealed from characterization studies, which was beneficial for enhancing phase separation and carrier transport. Those results demonstrated an effective strategy to improve the performance of NFSM-OSCs via fluorination of small molecular donors and modulation of crystallinity deviation between donors and acceptors.
关键词： morphology,all-small-molecule organic solar cells,crystallinity,fluorination,orientation modulation
更新于2025-09-12 10:27:22
-
13.34% Efficiency Nonfullerene All‐Small‐Molecule Organic Solar Cells Enabled by Modulating Crystallinity of Donors via a Fluorination Strategy
摘要： Nonfullerene all-small-molecule organic solar cells (NFSM-OSCs) have shown a promising potential towards the commercialization of OSCs, owing to their unique advantages of high purity, easy synthesis and good reproducibility. However, great challenges in the modulation of phase separation morphology have limited their future development. Herein, two novel small molecular donors of BTEC-1F and BTEC-2F, derived from the small molecule DCAO3TBDTT, were designed and synthesized. While using Y6 as the acceptor, the devices based on non-fluorinated DCAO3TBDTT showed an open circuit voltage (Voc) of 0.804 V and a power conversion efficiency (PCE) of 10.64%. Mono-fluorinated BTEC-1F showed an increased Voc of 0.870 V and a PCE of 11.33%. More impressively, the fill factor (FF) of di-fluorinated BTEC-2F based NFSM-OSC was largely improved to 72.35% resulting in an impressive PCE of 13.34%, which was much higher than that of BTEC-1F (61.35%) and DCAO3TBDTT (60.95%). To the best of our knowledge, this is the highest reported PCE to date for NFSM-OSCs. BTEC-2F depicted a more compact molecular stacking and a lower crystallinity as revealed from characterization studies, which was beneficial for enhancing phase separation and carrier transport. Those results demonstrated an effective strategy to improve the performance of NFSM-OSCs via fluorination of small molecular donors and modulation of crystallinity deviation between donors and acceptors.
关键词： morphology,all-small-molecule organic solar cells,crystallinity,fluorination,orientation modulation
更新于2025-09-12 10:27:22
-
Improved Efficiency in All-Small-Molecule Organic Solar Cells with Ternary Blend of Non-Fullerene Acceptor and Chlorinated and Non-Chlorinated Donors.
摘要： Ternary non-fullerene all-small-molecule organic solar cells (NFSM-OSCs) were developed by incorporating a non-fullerene acceptor (IDIC) and two structurally similar small molecular donors (SM and SM-Cl), where SM-Cl is a novel small molecular donor derived from the reported molecular donor SM. When doping 10% SM-Cl in SM:IDIC binary system, the power conversion efficiency (PCE) of ternary solar cell was dramatically increased from 9.39% to 10.29%. Characterization studies indicated that the two donors tend to form an alloy state, which effectively down-shifted the HOMO energy level of the donor, and thus promoting a higher open-circuit voltage. Interestingly, incorporating a third component (SM-Cl) with lower crystallinity was proven to facilitate the demixing between donors and acceptors, which was in contrary to the traditional findings of enhanced phase separation through incorporation of highly crystalline molecule. Although the morphological modulation had always been a bottleneck issue in NFSM-OSCs, the findings in this work indicated that the modulation on crystallinity deviation between donors and acceptors could be an effective method to further improve the performance of NFSM-OSCs, providing a new perspective on NFSM-OSCs.
关键词： alloy model,non-fullerene all-small-molecule solar cells,chlorinated molecular donor,ternary strategy,crystallinity modulation
更新于2025-09-12 10:27:22
-
Conjugation‐Curtailing of Benzodithionopyran‐Cored Molecular Acceptor Enables Efficient Air‐Processed Small Molecule Solar Cells
摘要： Small molecule solar cells (SMSCs) lag a long way behind polymer solar cells. A key limit is the less controllable morphology of small molecule materials, which can be aggravated when incorporating anisotropic nonfullerene acceptors. To fine-tune the blending morphology within SMSCs, a π-conjunction curtailing design is applied, which produces a efficient benzodithionopyran-cored molecular acceptor for nonfullerene SMSCs (NF-SMSCs). When blended with a molecular donor BDT3TR-SF to fabricate NF-SMSCs, the π-conjunction curtailed molecular acceptor NBDTP-M obtains an optimal power conversion efficiency (PCE) of up to 10.23%, which is much higher than that of NBDTTP-M of longer π-conjunction. It retains 93% of the PCE of devices fabricated in a glove box when all spin-coating and post-treating procedures are conducted in ambient air with relative humidity of 25%, which suggests the good air-processing capability of π-conjunction curtailed molecules. Detailed X-ray scattering investigations indicate that the BDT3TR-SF:NBDTP-M blend exhibits a blend morphology featuring fine interpenetrating networks with smaller domains and higher phase purity, which results in more efficient charge generation, more balanced charge transport, and less recombination compared to the low-performance BDT3TR-SF:NBDTTP-M blend. This work provides a guideline for molecular acceptors’ design toward efficient, low-cost, air-processed NF-SMSCs.
关键词： electron acceptors,all-small-molecule solar cells,air-processing,power conversion efficiency
更新于2025-09-11 14:15:04