Achieving over 16% efficiency for single-junction organic solar cells

To achieve high photovoltaic performance of bulk hetero-junction organic solar cells(OSCs), a range of critical factors including absorption profiles, energy level alignment, charge carrier mobility and miscibility of donor and acceptor materials should be carefully considered. For electron-donating materials, the deep highest occupied molecular orbital(HOMO) energy level that is beneficial for high open-circuit voltage is much appreciated. However, a new issue in charge transfer emerges when matching such a donor with an acceptor that has a shallower HOMO energy level. More to this point, the chemical strategies used to enhance the absorption coefficient of acceptors may lead to increased molecular crystallinity, and thus result in less controllable phase-separation of photoactive layer. Therefore, to realize balanced photovoltaic parameters, the donor-acceptor combinations should simultaneously address the absorption spectra, energy levels, and film morphologies. Here, we selected two non-fullerene acceptors, namely BTPT-4F and BTPTT-4F, to match with a wide-bandgap polymer donor P2F-EHp consisting of an imidefunctionalized benzotriazole moiety, as these materials presented complementary absorption and well-matched energy levels. By delicately optimizing the blend film morphology, we demonstrated an unprecedented power conversion efficiency of over 16% for the device based on P2F-EHp:BTPTT-4F, suggesting the great promise of materials matching toward high-performance OSCs.     

Comparison of surfactant-assisted shotgun methods using acid-labile surfactants and sodium dodecyl sulfate for membrane proteome analysis

Three surfactant-assisted shotgun methods using acid labile surfactants, sodium-3-[(2-methyl-2-undecyl-1,3-dioxolan-4-yl)-methoxyl]-1-propanesulfonate (RapiGest) and 3-[3-(1,1-bisalkyloxyethyl)pyridin-1-yl]propane-1-sulfonate (PPS), and sodium dodecyl sulfate (SDS) were investigated for their applicability to membrane proteome analysis. It is shown that RapiGest is a preferred reagent for handling membrane proteomes of Escherichia coli and MCF7 cells for liquid chromatography tandem mass spectrometry (LC MS/MS) analysis of tryptic digests. The RapiGest method allowed identification of more peptides and proteins than the SDS and PPS methods and there was no apparent bias for the type of peptides and proteins identified by the RapiGest and SDS methods, while a slightly higher proportion of hydrophilic peptides and proteins were identified by the PPS method. The performance of the SDS and PPS methods is similar in terms of the numbers of peptides and proteins identified. Since the SDS method required the removal of SDS using a technique such as strong-cation exchange (SCX), we further investigated the effect of SCX on sample loss through analyzing the digest of an enriched E. coli membrane fraction as well as a standard protein, bovine serum albumin (BSA). The results showed that extensive sample loss (as much as 62%) was encountered during the SCX cleaning step. We then applied the RapiGest method in combination with two-dimensional LC MS/MS to characterize the E. coli membrane proteome. In total, 1626 unique proteins (5799 unique peptides) were identified with a peptide false discovery rate of 2.4%. About 60% of the identified proteins with known cellular locations were found to be membrane proteins. Among them, about 75% were integral membrane proteins. This work represents one of the most comprehensive profiles of E. coli membrane proteome generated by a proteomic technique.     

发现于温州的浙江植物区系新资料

报道了发现于温州的2个浙江植物分布新记录属和4个新记录种,2个新记录属分别是吻兰属(Collabium Bl.)和刺蕊草属(Pogostemon Desf.),4个新记录种分别是台湾吻兰(Collabium formosanum Hayata)、翘距虾脊兰(Calanthe aristulifera Rchb. f.)、水珍珠菜(Pogostemon auricularius (Linn.) Kassk.)和疏花车前(Plantago asiatica Linn. subsp. erosa (Wall.) Z Y LI).凭证标本保存于温州大学标本馆(WZU).     

Improving photovoltaic parameters of all-polymer solar cells through integrating two polymeric donors

Science China Chemistry - The incorporation of an additional component into the bulk-heterojunction light-harvesting layer of polymer solar cells has been considered as an effective strategy to...     

Electrical characteristics and low-temperature sintering of BiFeO3-modified Pb(Zr,Ti)O3–Pb(Fe2/3W1/3)O3–Pb(Mn1/3Nb2/3)O3 ceramics with ZnO addition

Effects of ZnO addition on electrical properties and low-temperature sintering of BiFeO₃-modified Pb(Zr,Ti)O₃–Pb(Fe_2/3W_1/3)O₃–Pb(Mn_1/3Nb_2/3)O₃ were investigated. The investigations revealed that the sintering temperature can be decreased to 950 °C, and the favorable properties were obtained with 0.10 wt% ZnO added ceramics. The electrical properties were as follows: d₃₃ = 313 pC/N, K_p = 0.56, tan δ = 0.0053, ε_r = 1407 and T_c = 295 °C, which showed that this system was a promising material for the multilayer devices application.     

Zinc binding in HDAC inhibitors: a DFT study

Histone deacetylases (HDACs) are attractive targets for the treatment of cancers and a variety of other diseases. Most currently studied HDAC inhibitors contain hydroxamic acids, which are potentially problematic in the development of practical drugs. DFT calculations of the binding modes and free energies of binding for a variety of other functionalities in a model active site of HDAC are described. The protonation state of hydroxamic acids in the active site and the origin of the high affinity are discussed. These results emphasize the importance of a carefully chosen pKa for zinc binding and provide guidance for the design of novel, non-hydroxamic acid HDAC inhibitors.     

LSMO/SiO2复合材料变温微波吸收特性研究

通过固相反应法制备了LSMO/SiO2复合材料, 测试了LSMO材料500 MHz～18 GHz介电特性和LSMO/SiO2复合材料样品不同温度下X波段介电常数和微波吸收特性. 测试结果表明, 在12 GHz附近复合材料样品有明显的介电损耗特征峰, 随着温度的升高材料的介电常数虚部明显升高, tgδ变大;吸收特性测试表明, 随着温度升高, 吸收峰升高, 吸收峰略微往低频移动.     

Phenylboronic acid-functionalized glycogens as dynamic nano-frameworks for conjugation and activation of carbonic anhydrase

Biocatalysis is playing an increasingly important role for chemical, pharmaceutical, and food industries, owing to its high efficiency, selectivity and environment-friendliness. However, it remains challenging to improve the catalytic activity of enzymes since the most frequently used strategies are costly and time-consuming. In the current study, a new type of glycogen-based dynamic nano-frameworks is prepared as additives for the direct activation of carbonic anhydrase (bovine erythrocytes [bCA]). The boronic acid functionalization of the branched glycogen structures can provide N B coordination with bCA, leading to the conjugation and stabilization of the target enzyme. As a result, the glycogen with a 10% substitution degree ( Gly-PBA ₁₀ ) showed a higher activation effect for bCA than that of glycogen with a 20% substitution degree ( Gly-PBA ₂₀ ). Furthermore, the mechanism for interactions between the dynamic frameworks and bCA has been studied through combined techniques of dynamic light scattering, circular dichroism spectroscopy, and isothermal titration calorimetry. The results suggested different protein binding modes and stabilization abilities for the protein secondary structures from these two types of functionalized dynamic frameworks. This study provided new insights into the protein-polymer interactions that can be beneficial for various biochemical applications.     

Coupling Benzylamine Oxidation with CO2 Photoconversion to Ethanol over a Black Phosphorus and Bismuth Tungstate S-Scheme Heterojunction

Photoconversion of CO₂ and H₂O into ethanol is an ideal strategy to achieve carbon neutrality. However, the production of ethanol with high activity and selectivity is challenging owing to the less efficient reduction half-reaction involving multi-step proton-coupled electron transfer (PCET), a slow C−C coupling process, and sluggish water oxidation half-reaction. Herein, a two-dimensional/two-dimensional (2D/2D) S-scheme heterojunction consisting of black phosphorus and Bi₂WO₆ (BP/BWO) was constructed for photocatalytic CO₂ reduction coupling with benzylamine (BA) oxidation. The as-prepared BP/BWO catalyst exhibits a superior photocatalytic performance toward CO₂ reduction, with a yield of 61.3 μmol g⁻¹ h⁻¹ for ethanol (selectivity of 91 %).In situ spectroscopic studies and theoretical calculations reveal that S-scheme heterojunction can effectively promote photogenerated carrier separation via the Bi−O−P bridge to accelerate the PCET process. Meanwhile, electron-rich BP acts as the active site and plays a vital role in the process of C−C coupling. In addition, the substitution of BA oxidation for H₂O oxidation can further enhance the photocatalytic performance of CO₂ reduction to C₂H₅OH. This work opens a new horizon for exploring novel heterogeneous photocatalysts in CO₂ photoconversion to C₂H₅OH based on cooperative photoredox systems.     

La0.67Sr0.33Mn1-yFeyO3(y=0, 0.01, 0.02, 0.03)磁谱特性分析

采用固相反应法制备了La0．67Sr0．33Mn1-yFeyO3（y=0,0．01,0．02,0．03）氧化物多晶样品,XRD测试表明形成了钙钛矿单相结构,铁掺人后材料的晶体结构没有明显变化。SEM测试表明样品晶粒大小为1～3μm,随着铁含量增加饱和磁化强度下降。样品室温磁导率（10kHz～1．8GHz）测试表明,复磁导率频谱曲线是典型的弛豫型谱线,且随铁离子含量增加其起始磁导率下降。同时通过最小二乘曲线拟合的方法分析了频谱曲线,分别给出了畴壁位移和磁畴转动对磁导率的贡献,结果表明,y=0,0．01的样品畴壁位移对磁导率的贡献大于畴转对磁导率的贡献,y=0．02,0．03的样品,畴转对磁导率的贡献大于畴壁位移的贡献。