锌卟啉自组装在染料敏化太阳能电池中的应用（英文）

制备了2种锌卟啉天线分子P2与P3,并通过自组装的方法成功地将这些天线分子应用到了染料敏化太阳能电池之中。与传统的D-π-A结构的染料相比,这种策略显示出了明显的优势:可以避免复杂的合成步骤,还可以通过调节天线分子和锚固基团的结构去改善染料的光子捕获能力并减少电荷复合行为。当4-吡啶-4-基苯甲酸(A)作为锚固基团时,经过分子自组装之后,基于A-P2的电池器件显示出了1.68%的转换效率,开路电压为526 mV,短路电流密度为5.39 mA·cm~(-2),这充分说明了自组装策略在染料敏化太阳能电池中得到了很好的应用。而基于A-P3的电池器件能量转换效率只有0.79%,这可能主要是因为天线分子P3较大的位阻减小了染料吸附量的原因造成的。我们另外也测试比较了它们在光学、电化学、光伏性能等方面的差异。     

锌卟啉自组装在染料敏化太阳能电池中的应用

制备了2种锌卟啉天线分子P2与P3，并通过自组装的方法成功地将这些天线分子应用到了染料敏化太阳能电池之中。与传统的D-π-A结构的染料相比，这种策略显示出了明显的优势：可以避免复杂的合成步骤，还可以通过调节天线分子和锚固基团的结构去改善染料的光子捕获能力并减少电荷复合行为。当4-吡啶-4-基苯甲酸（A）作为锚固基团时，经过分子自组装之后，基于A-P2的电池器件显示出了1.68%的转换效率，开路电压为526 mV，短路电流密度为5.39 mA·cm^-2，这充分说明了自组装策略在染料敏化太阳能电池中得到了很好的应用。而基于A-P3的电池器件能量转换效率只有0.79%，这可能主要是因为天线分子P3较大的位阻减小了染料吸附量的原因造成的。我们另外也测试比较了它们在光学、电化学、光伏性能等方面的差异。     

方酸菁染料掺杂聚对苯乙炔太阳电池研究

本文把方酸菁染料掺杂在聚[2-甲氧基-5(2-乙基己氧基)对苯乙炔](MEH-PPV)共轭聚合物中,利用方酸菁染料在可见光的良好吸收以提高器件对光谱的利用。用Ti(OC3H7)4作为纳米TiO2前驱物直接和MEH-PPV、方酸菁染料(Hydroxy Squaraine,Sq)混合旋涂来制作连续的互穿网络器件。通过紫外-可见光吸收光谱得到掺杂后体系在650nm左右吸收得到加强,通过荧光测试发现体系MEH-PPV(5mg/mL)∶Sq(0.1mg/1mL)为4∶1(v∶v)掺杂Ti(OC3H7)4(80μL/mL)体积为50%时,荧光几乎被完全淬灭。测试了器件ITO/MEH-PPV/∶Sq∶TiO2/A,ITO/TiO2/MEH-PPV∶Squaraine∶TiO2/A l的光电性能,在AM=1.5,1000W/m2白光下单层器件的FF为0.31,Voc=54Mv,Isc=1.4mA,能量转换效率为0.008%。在同样条件下双层器件FF为0.12,Voc=203mV,Isc=0.048mA,能量转换效率为0.009%。     

电荷分离型染料在固态染料敏化太阳能电池中的应用研究

染料敏化太阳能电池中的染料起到吸收光能和传导光生电子的作用,而染料的电荷分离状态能有效提高电子注入效率,抑制电荷复合,进而提高器件性能。本文以电荷分离(CS)型染料为敏化剂,采用spiro-OMeTAD为空穴传输材料制备了全固态染料敏化太阳能电池,分析了TiO_2光阳极膜厚的影响,当TiO_2光阳极膜厚为1. 2μm时,器件性能最优;探讨了染料结构对器件性能的影响,其中染料MTPABT-Pyc的器件性能最好,其光电流和效率分别为7. 38mA/cm~2和3. 06%。相比于电荷转移(CT)型染料MTPAcc,MTPABTPyc具有相近的捕光能力,但是其效率比MTPAcc (2. 64%)提高了16%。研究结果表明,CS型染料的电荷分离态对电荷复合的抑制和空穴的传输具有明显的优势。     

基于不同取代基的噻吩-三苯胺染料敏化剂的合成与光伏性能

本文合成了含3种不同取代基的噻吩-三苯胺染料敏化剂(H1,H2和H3),并将其应用于二氧化钛纳米晶染料敏化太阳能电池.系统地研究了3种染料的光物理、电化学和光伏性能.基于H1的染料敏化太阳能电池获得了9.10%的光电转换效率(Voc=0.72V,Jsc=18.03mAcm-2,FF=0.70).     

3-氨基丙基三甲氧基硅烷自组装提高染料敏化太阳能电池的效率

以3-氨基丙基三甲氧基硅烷(APTS)修饰的二氧化钛为负极制备的染料敏化太阳能电池在100 mW·cm^-2的模拟太阳光照下的短路电流、开路电压、光电转换效率分别为18.32 mA·cm^-2、775.9 mV、9.15%. 而没有经过ATPS修饰的电池三项性能参数分别为18.08 mA·cm^-2、749.9 mV、7.70%, 修饰后电池的光电转换效率提高了18.8%, 同时填充因子由0.57提高为0.64. 暗电流-电压曲线显示起始电压从-0.30 V变化到-0.40 V, 表明二氧化钛电极和电解液之间的暗反应得到了有效抑制, APTS作为阻挡层减少了二氧化钛电极表面的缺陷与表面态. 另外, 通过实验设计, 将APTS与染料层-层自组装于二氧化钛电极上, 通过X射线光电子能谱(XPS)研究了二氧化钛层、APTS、染料的作用形式. 定性与定量结果表明: APTS中的乙氧基部分脱除后形成了Si―O―Ti单桥或者双桥键, 钌染料cis-Ru(dcpyH₂)₂(SCN)₂通过分子中的部分―COOH与APTS中的―NH₂形成的静电作用力吸附在TiO₂电极上. 傅里叶变换红外(FT-IR)光谱的结果进一步证明了这种分子间作用.     

染料敏化太阳电池中TiO2/染料/电解质界面的修饰

染料敏化太阳电池(DSC)作为新型太阳电池自问世以来受到了广泛关注, 其系统内部的接触界面尤其是TiO₂/染料/电解质界面一直是该领域的研究热点. 光敏染料的吸附以及电子的注入、传输和复合都发生在该界面, 其界面性质对DSC性能具有很大影响. 对染料敏化太阳电池中TiO₂/染料/电解质界面进行修饰可以有效抑制染料聚集和电子复合, 提高电子的注入效率与传输速率; 同时, 对TiO₂导带边的位置及染料吸附等也产生一定的影响, 最终提高电池的光电转换效率和稳定性. 本文主要从不同的修饰途径详细评述了TiO₂/染料/电解质界面修饰方法及机理研究进展,包括TiO₂光阳极的修饰改性、染料溶液中共吸附剂的引入和多种染料共敏化处理以及电解质中不同功能添加剂的应用. 指出了这些修饰方法目前存在的主要问题, 并对未来的发展方向进行了展望.     

敏化染料分子长径比对太阳能电池性能的影响

采用同一系列但分子长径比不同的3种染料:2-氰基-3-[2-[4-{2-[4-N,N-二(4-甲基苯基)氨基苯基]乙烯基}-苯基氨基)-嘧啶-5-取代基]-丙烯酸(MTPA-Pyc)、2-氰基-3-(4-{2-[4-N,N-二(4-甲基苯基)氨基苯基]乙烯基}-苯基)-丙烯酸(MTPAcc)和2-氰基-3-[4-N,N-二(4-甲基苯基)氨基苯基]-丙烯酸(MTPAc),研究了在不同吸附溶剂中3种染料分子在Ti O2上的吸附量和聚集态,探讨了敏化染料分子长径比对染料敏化太阳电池性能的影响.结果表明,MTPAcc具有最合适的分子长径比,其在Ti O2表面的吸附量及应用的光电性能最高;吸附溶剂的极性增大有利于提高染料的吸附量,但也会影响染料分子的聚集态.当以四氢呋喃为吸附溶剂时,MTPAcc在Ti O2表面的吸附量大且不发生聚集,对应的敏化太阳能电池器件在所有结果中表现最好,在490 nm处的单色光光电转化效率(IPCE)极值达到84%,总光电转化效率(η)达到5.72%.     

不同受体结构染料共敏化对染料敏化太阳电池性能的影响（英文）

为了拓宽染料敏化太阳电池对太阳光谱的响应范围,提高电池的光电转换效率,将两种含有不同受体结构(绕丹宁-3-乙酸基(RA)和氰基丙烯酸基(CA))的三苯胺染料(TR1和TC1)进行共敏化。TR1染料平伏吸附在TiO_2表面,而TC1染料直立吸附在TiO_2表面。将两种染料按照不同摩尔比共敏化TiO_2后,TC1占据TR1的部分位置,拓展光谱的同时也抑制了电荷复合,电子寿命较TR1敏化的太阳电池长。在TR1与TC1摩尔比为5∶5的共敏剂溶液敏化的共敏电池器件中,短路光电流密度(J_(sc))为11.7 mA/cm~2,开路电压(V_(oc))为704 mV,填充因子(FF)为0.73,光电转换效率(η)为6.03%。该结果明显优于单一染料敏化的电池器件。     

不同受体结构染料共敏化对染料敏化太阳电池性能的影响

为了拓宽染料敏化太阳电池对太阳光谱的响应范围,提高电池的光电转换效率,将两种含有不同受体结构（绕丹宁-3-乙酸基（RA）和氰基丙烯酸基（CA））的三苯胺染料（TR1和TC1）进行共敏化。TR1染料平伏吸附在TiO₂表面,而TC1染料直立吸附在TiO₂表面。将两种染料按照不同摩尔比共敏化TiO₂后,TC1占据TR1的部分位置,拓展光谱的同时也抑制了电荷复合,电子寿命较TR1敏化的太阳电池长。在TR1与TC1摩尔比为5：5的共敏剂溶液敏化的共敏电池器件中,短路光电流密度（J_sc）为11.7 mA/cm²,开路电压（V_oc）为704 mV,填充因子（FF）为0.73,光电转换效率（η）为6.03%。该结果明显优于单一染料敏化的电池器件。     

Synthesis and applications of novel acceptor-donor-acceptor organic dyes with dithienopyrrole- and fluorene-cores for dye-sensitized solar cells

Four novel symmetrical organic dyes (S1-S4) configured with acceptor-donor-acceptor (A-D-A) structures containing electron donating fluorene (S1 and S2) and N-alkyl dithieno[3,2-b:2′,3′-d]pyrrole (DTP) (S3 and S4) cores terminated with two anchoring cyanoacrylic acids (as electron acceptors) were synthesized and applied to dye-sensitized solar cells (DSSCs). The DSSC device based on S2 dye showed the best photovoltaic performance among S1-S4 dyes: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 76%, a short circuit current (J_SC) of 12.27 mA/cm², an open circuit voltage (V_OC) of 0.61 V, a fill factor (FF) of 0.63, and an overall power conversion efficiency (η) of 4.73%. Besides, the utilization of chenodoxycholic acid (CDCA) as a co-adsorbent in the DSSC device based on S3 dye showed a significant improvement in its η value (from 3.70% to 4.31%), which is attributed to the suppression of dye aggregation on TiO₂ surface and thus to increase the J_SC value eventually.     

Molecular Stacking and Aggregation Optimization of Photoactive Layer through Solid Additive Enables High-Performance Organic Solar Cells

Regulating molecular packing and aggregation of photoactive layer is a critical but challenging issue in developing high-performance organic solar cells. Herein, two structurally similar analogues of anthra[2,3-b : 6,7-b′]dithiophene (ADT) and naphtho[1,2-b : 5,6-b′]dithiophene (NDT) are developed as solid additive to exploit their effect in regulating the molecular aggregation and π-stacking of photoactive layer. We clarify that the perpendicular arrangements of NDT can enlarge the molecular packing space and improve the face-on stacking of Y6 during the film formation, favoring a more compact and ordered long-range π-π stacking in the out-of-plane direction after the removal of NDT under thermal annealing. The edge-to-face stacked herringbone-arrangement of ADT along with its non-volatilization under thermal annealing can induce the coexistence of face-on and edge-on stacking of blend film. As a result, the NDT treatment shows encouraging effect in improving the photovoltaic performance of devices based on various systems. Particularly, a remarkable PCE of 18.85 % is achieved in the PM6 : L8-BO-based device treated by NDT additive, which is a significant improvement with regard to the PCE of 16.41 % for the control device. This work offers a promising strategy to regulate the molecular packing and aggregation of photoactive layer towards significantly improved performance and stability of organic solar cells.     

D-A-D-based Unsymmetrical Thiosquaraine Dye for the Dye-Sensitized Solar Cells†

In dye-sensitized solar cell, modulating the electronic properties of the sensitizer by varying the donor, π-spacer, acceptor and anchoring groups help optimizing the structure of the dye for better device performance. Here, a donor–acceptor–donor-based unsymmetrical thiosquaraine sensitizer ( SQ5S ) has been designed and synthesized. Photophysical, electrochemical, theoretical and photovoltaic characterizations of SQ5S dye have been compared with its oxygen analog, SQ5 . The incorporation of the sulfur atom in the acceptor unit of SQ5S dye showed an intense peak at 688 nm, which was 38 nm of red-shifted and showed the panchromatic light harvesting response with the onset of 850 nm compared with SQ5 dye. The LUMO and HOMO energy levels are well aligned with the conduction band of TiO₂ and the redox potential of electrolyte for the charge injection and the dye-regeneration processes, respectively. Photovoltaic efficiency of 1.51% (V_OC 610 mV, J_SC 3.07 mA cm⁻², ff 81%) has been achieved for SQ5S dye, whereas SQ5 showed the device performance of 5.43% (V_OC 723 mV, J_SC 9.3 mA cm⁻², ff 80%). The decreased device performance for the dye SQ5S has been attributed to the favorable intersystem crossing process associated with the photoexcited SQ5S that reduces the driving force for the charge injection process.     

Cyclometalated Ruthenium(II) Complexes Featuring Tridentate Click‐Derived Ligands for Dye‐Sensitized Solar Cell Applications

A series of heteroleptic bis(tridentate) Ru^II complexes featuring N^C^N‐cyclometalating ligands is presented. The 1,2,3‐triazole‐containing tridentate ligands are readily functionalized with hydrophobic side chains by means of click chemistry and the corresponding cyclometalated Ru^II complexes are easily synthesized. The performance of these thiocyanate‐free complexes in a dye‐sensitized solar cell was tested and a power conversion efficiency (PCE) of up to 4.0 % (J_sc=8.1 mA cm^?2, V_oc=0.66 V, FF=0.70) was achieved, while the black dye ((NBu₄)₃[Ru(Htctpy)(NCS)₃]; Htctpy=2,2′:6′,2′′‐terpyridine‐4′‐carboxylic acid‐4,4′′‐dicarboxylate) showed 5.2 % (J_sc=10.7 mA cm^?2, V_oc=0.69 V, FF=0.69) under comparable conditions. When co‐adsorbed with chenodeoxycholic acid, the PCE of the best cyclometalated dye could be improved to 4.5 % (J_sc=9.4 mA cm^?2, V_oc=0.65 V, FF=0.70). The PCEs correlate well with the light‐harvesting capabilities of the dyes, while a comparable incident photon‐to‐current efficiency was achieved with the cyclometalated dye and the black dye. Regeneration appeared to be efficient in the parent dye, despite the high energy of the highest occupied molecular orbital. The device performance was investigated in more detail by electrochemical impedance spectroscopy. Ultimately, a promising Ru^II sensitizer platform is presented that features a highly functionalizable “click”‐derived cyclometalating ligand.     

Facile Synthesis of a Furan–Arylamine Hole‐Transporting Material for High‐Efficiency,Mesoscopic Perovskite Solar Cells

A novel hole‐transporting molecule (F101) based on a furan core has been synthesized by means of a short, high‐yielding route. When used as the hole‐transporting material (HTM) in mesoporous methylammonium lead halide perovskite solar cells (PSCs) it produced better device performance than the current state‐of‐the‐art HTM 2,2′,7,7′‐tetrakis‐(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene (spiro‐OMeTAD). The F101‐HTM‐based device exhibited both slightly higher J_sc (19.63 vs. 18.41 mA cm^?2) and V_oc (1.1 vs. 1.05 V) resulting in a marginally higher power conversion efficiency (PCE) (13.1 vs. 13 %). The steady‐state and time‐resolved photoluminescence show that F101 has significant charge extraction ability. The simple molecular structure, short synthesis route with high yield and better performance in devices makes F101 an excellent candidate for replacing the expensive spiro‐OMeTAD as HTM in PSCs.     

13.34 % Efficiency Non‐Fullerene All‐Small‐Molecule Organic Solar Cells Enabled by Modulating the Crystallinity of Donors via a Fluorination Strategy

Non‐fullerene all‐small‐molecule organic solar cells (NFSM‐OSCs) have shown potential as OSCs, owing to their high purity, easy synthesis and good reproducibility. However, challenges in the modulation of phase separation morphology have limited their development. Herein, two novel small molecular donors, BTEC‐1F and BTEC‐2F, derived from the small molecule DCAO3TBDTT, are synthesized. Using Y6 as the acceptor, devices based on non‐fluorinated DCAO3TBDTT showed an open circuit voltage (V_oc) of 0.804 V and a power conversion efficiency (PCE) of 10.64 %. Mono‐fluorinated BTEC‐1F showed an increased V_oc of 0.870 V and a PCE of 11.33 %. The fill factor (FF) of di‐fluorinated BTEC‐2F‐based NFSM‐OSC was improved to 72.35 % resulting in a PCE of 13.34 %, which is higher than that of BTEC‐1F (61.35 %) and DCAO3TBDTT (60.95 %). To our knowledge, this is the highest PCE for NFSM‐OSCs. BTEC‐2F had a more compact molecular stacking and a lower crystallinity which enhanced phase separation and carrier transport.     

Two-Dimensional Metal–Organic Framework Nanosheets with Cobalt-Porphyrins for High-Performance CO2 Electroreduction

The electrochemical reduction of CO₂ presents a promising strategy to mitigate the greenhouse effect and reduce excess carbon dioxide emission to realize a carbon-neutral energy cycle, but it suffers from the lack of high-performance electrocatalysts. In this work, catalytic active cobalt porphyrin [TCPP(Co)=(5,10,15,20)-tetrakis(4-carboxyphenyl)porphyrin-Co^II] was precisely anchored onto water-stable 2D metal–organic framework (MOF) nanosheets (Zr-BTB) to obtain ultrathin 2D MOF nanosheets [TCPP(Co)/Zr-BTB] with accessible catalytic sites for the CO₂ reduction reaction. Compared with molecular cobalt porphyrin, the TCPP(Co)/Zr-BTB exhibits an ultrahigh turnover frequency (TOF=4768 h⁻¹ at −0.919 V vs. reversible hydrogen electrode, RHE) owing to high active-site utilization. In addition, three post-modified 2D MOF nanosheets [TCPP(Co)/Zr-BTB-PABA, TCPP(Co)/Zr-BTB-PSBA, TCPP(Co)/Zr-BTB-PSABA] were obtained, with the modifiers of p-(aminomethyl)benzoic acid (PABA), p-sulfobenzoic acid potassium (PSBA), and p-sulfamidobenzoic acid (PSABA), to change the micro-environments around TCPP(Co) through the tuning of steric effects. Among them, the TCPP(Co)/Zr-BTB-PSABA exhibited the best performance with a faradaic efficiency (FE_CO) of 85.1 %, TOF of 5315 h⁻¹, and j_total of 6 mA cm⁻² at −0.769 V (vs. RHE). In addition, the long-term durability of the electrocatalysts is evaluated and the role of pH buffer is revealed.     

New Organic Dye Based on a 3,6‐Disubstituted Carbazole Donor for Efficient Dye‐Sensitized Solar Cells

We have synthesized and characterized four organic dyes ( 9 , 10 , H1 , H2 ) based on a 3,6‐disubstituted carbazole donor as sensitizers in dye‐sensitized solar cells. These dyes have high molar extinction coefficients and energy levels suitable for electron transfer from an electrolyte to nanocrystalline TiO₂ particles. Under standard air mass 1.5 global (AM 1.5 G) solar irradiation, a device using dye H4 exhibits a short‐circuit current density (J_sc) of 13.7 mA cm^?2, an open‐circuit voltage (V_oc) of 0.68 V, a fill factor (FF) of 0.70, and a calculated efficiency of 6.52 %. This performance is comparable to that of a reference cell based on N719 (7.30 %) under the same conditions. After 1000 hours of visible‐light soaking at 60 °C, the overall efficiency remained at 95 % of the initial value.     

Molecular Engineering of Simple Phenothiazine‐Based Dyes To Modulate Dye Aggregation,Charge Recombination,and Dye Regeneration in Highly Efficient Dye‐Sensitized Solar Cells

A series of simple phenothiazine‐based dyes, namely, TP , EP , TTP , ETP , and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye‐sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (J_sc=15.2 mA cm^?2, V_oc=0.783 V, fill factor (FF)=0.679) and 7.87 % (J_sc=16.1 mA cm^?2, V_oc=0.717 V, FF=0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I^?/I₃^? redox couple. By replacing the T group with the E unit, EP ‐based DSSCs had a slightly lower PCE of 7.98 % with a higher short‐circuit photocurrent (J_sc) of 16.7 mA cm^?2. The dye ETP , with a mixture of E and T, had an even lower PCE of 5.62 %. Specifically, the cell based on the dye EEP , with a dimer of E, had inferior J_sc and V_oc values and corresponded to the lowest PCE of 2.24 %. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies.     

An Oligothiophene–Fullerene Molecule with a Balanced Donor–Acceptor Backbone for High‐Performance Single‐Component Organic Solar Cells

A new balanced donor–acceptor molecule, namely, benzodithiophene (BDT)‐rhodanine‐[6,6]‐phenyl‐C₇₁ butyric acid methyl ester (Rh‐PC₇₁BM) comprising two covalently linked blocks, a p‐type oligothiophene‐containing BDT‐based moiety and an n‐type PC₇₁BM unit was designed and synthesized. The single‐component organic solar cell (SCOSC) fabricated from Rh‐PC₇₁BM molecules showed a power conversion efficiency (PCE) of 3.22 % with an open‐circuit voltage (V_oc) of 0.98 V. These results rank are among the highest values for SCOSCs based on a monomolecular material. In particular, the one‐molecule Rh‐PC₇₁BM device exhibits excellent thermal stability compared to reference Rh‐OH:PC₇₁BM device. The success of our monomolecular strategy can provide a new way to develop high‐performance SCOSCs.