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Lau GPS, Tsao HN, Yi C, Zakeeruddin SM, Grätzel M, Dyson PJ. Enhancing the stability of porphyrin dye-sensitized solar cells by manipulation of electrolyte additives. CHEMSUSCHEM 2015; 8:255-259. [PMID: 25488713 DOI: 10.1002/cssc.201403225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Indexed: 06/04/2023]
Abstract
The use of porphyrin-based photosensitizers with superior light-harvesting properties has enabled the power conversion efficiency of dye-sensitized solar cells (DSCs) to reach 13 % under full sun illumination. However, a major limitation of such devices corresponds to the volatility of the solvent used so far for the electrolyte, which prevents practical applications. In this work, we describe a porphyrin-ionic liquid DSC, which not only affords the highest efficiency reported to date, but is also stable for more than 300 h under continuous full sun illumination at 60 °C. Furthermore, we identify a previously unreported pathway for device degradation, and show that the addition of N-methylbenzimidazole and a thiocyanate salt to the electrolyte is critical to obtaining long-lived devices.
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Geng Y, Yi C, Bircher MP, Decurtins S, Cascella M, Grätzel M, Liu SX. Anthanthrene dye-sensitized solar cells: influence of the number of anchoring groups and substitution motif. RSC Adv 2015. [DOI: 10.1039/c5ra21917e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Four anthanthrene-based molecules were synthesized as sensitizers in dye-sensitized solar cells, leading to the best overall efficiency up to 5.3%.
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53
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Li Z, Li H, Chen S, Froehlich T, Yi C, Schönenberger C, Calame M, Decurtins S, Liu SX, Borguet E. Regulating a benzodifuran single molecule redox switch via electrochemical gating and optimization of molecule/electrode coupling. J Am Chem Soc 2014; 136:8867-70. [PMID: 24933522 DOI: 10.1021/ja5034606] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report a novel strategy for the regulation of charge transport through single molecule junctions via the combination of external stimuli of electrode potential, internal modulation of molecular structures, and optimization of anchoring groups. We have designed redox-active benzodifuran (BDF) compounds as functional electronic units to fabricate metal-molecule-metal (m-M-m) junction devices by scanning tunneling microscopy (STM) and mechanically controllable break junctions (MCBJ). The conductance of thiol-terminated BDF can be tuned by changing the electrode potentials showing clearly an off/on/off single molecule redox switching effect. To optimize the response, a BDF molecule tailored with carbodithioate (-CS2(-)) anchoring groups was synthesized. Our studies show that replacement of thiol by carbodithioate not only enhances the junction conductance but also substantially improves the switching effect by enhancing the on/off ratio from 2.5 to 8.
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54
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Han S, Choi S, Park S, Jung H, Kim M, Yi C, Yoo H, Ji Y, Kim K. SU-E-T-315: The Change of Optically Stimulated Luminescent Dosimeters (OSLDs) Sensitivity by Accumulated Dose and High Dose. Med Phys 2014. [DOI: 10.1118/1.4888648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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55
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Wang W, Yi C. Molecular dynamics understanding on tensile behaviours of cold welding experiments of <100> oriented ultra-thin gold nanowires. ACTA ACUST UNITED AC 2014. [DOI: 10.1179/1432891714z.000000000540] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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56
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Lee S, Choi S, Min C, Ji Y, Jung H, Kim M, Yoo H, Kim C, Yi C, kim K. SU-E-J-106: Study of Variation of Internal Taget Volume Between 4DCT and Slow-CT in Respiratory Patterns Using Respiratory Motion Phantom. Med Phys 2014. [DOI: 10.1118/1.4888158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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57
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Yang J, Ganesan P, Teuscher J, Moehl T, Kim YJ, Yi C, Comte P, Pei K, Holcombe TW, Nazeeruddin MK, Hua J, Zakeeruddin SM, Tian H, Grätzel M. Influence of the donor size in D-π-A organic dyes for dye-sensitized solar cells. J Am Chem Soc 2014; 136:5722-30. [PMID: 24655036 DOI: 10.1021/ja500280r] [Citation(s) in RCA: 191] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We report two new molecularly engineered push-pull dyes, i.e., YA421 and YA422, based on substituted quinoxaline as a π-conjugating linker and bulky-indoline moiety as donor and compared with reported IQ4 dye. Benefitting from increased steric hindrance with the introduction of bis(2,4-dihexyloxy)benzene substitution on the quinoxaline, the electron recombination between redox electrolyte and the TiO2 surface is reduced, especially in redox electrolyte employing Co(II/III) complexes as redox shuttles. It was found that the open circuit photovoltages of IQ4, YA421, and YA422 devices with cobalt-based electrolyte are higher than those with iodide/triiodide electrolyte by 34, 62, and 135 mV, respectively. Moreover, the cells employing graphene nanoplatelets on top of gold spattered film as a counter electrode (CE) show lower charge-transfer resistance compared to platinum as a CE. Consequently, YA422 devices deliver the best power conversion efficiency due to higher fill factor, reaching 10.65% at AM 1.5 simulated sunlight. Electrochemical impedance spectroscopy and transient absorption spectroscopy analysis were performed to understand the electrolyte influence on the device performances with different counter electrode materials and donor structures of donor-π-acceptor dyes. Laser flash photolysis experiments indicate that even though the dye regeneration of YA422 is slower than that of the other two dyes, the slower back electron transfer of YA422 contributes to the higher device performance.
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58
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Yi C, Giordano F, Cevey-Ha NL, Tsao HN, Zakeeruddin SM, Grätzel M. Influence of structural variations in push-pull zinc porphyrins on photovoltaic performance of dye-sensitized solar cells. CHEMSUSCHEM 2014; 7:1107-1113. [PMID: 24616370 DOI: 10.1002/cssc.201301271] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/09/2014] [Indexed: 06/03/2023]
Abstract
We designed and synthesized two new zinc porphyrin dyes for dye-sensitized solar cells (DSCs). Subtle molecular structural variation in the dyes significantly influenced the performance of the DSC devices. By utilizing these dyes in combination with a cobalt-based redox electrolyte using a photoanode made of mesoporous TiO2 , we achieved a power conversion efficiency (PCE) of up to 12.0 % under AM 1.5 G (100 mW cm(-2)) simulated solar light. Moreover, we obtained a high PCE of 6.4 % for solid-state dye-sensitized solar cells by using 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene as a hole-transporting material.
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59
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Yi C, He C. DNA Repair by Reversal of DNA Damage. Cold Spring Harb Perspect Biol 2014. [DOI: 10.1101/cshperspect.a023440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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60
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Zhou X, Zhang CZ, Lu SX, Chen GG, Li LZ, Liu LL, Yi C, Fu J, Hu W, Wen JM, Yun JP. miR-625 suppresses tumour migration and invasion by targeting IGF2BP1 in hepatocellular carcinoma. Oncogene 2014; 34:965-77. [PMID: 24632613 DOI: 10.1038/onc.2014.35] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 12/29/2013] [Accepted: 01/01/2014] [Indexed: 02/07/2023]
Abstract
Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies and the third leading cause of cancer-related deaths worldwide. Tumour metastasis is one of the major causes of high mortality. microRNAshave been implicated in HCC metastasis. In this study, we found that miR-625 was frequently downregulated in HCC samples. A decrease in miR-625 was significantly correlated with lymph node anddistance metastasis (P=0.013), the presence of portal venous invasion (P=0.036), tumor-node-metastasis (TNM) stage (P=0.027) and unfavourable overall survival (P=0.003). Compared with primary tumours, miR-625 expression was markedly reduced in portal venous metastatic tumours. Re-expression of miR-625 in HCC cells was remarkably effective in suppressing cell migration andinvasiveness in vitro and in vivo. Mechanistically, miR-625 was confirmed to downregulate IGF2 mRNA-binding protein 1(IGF2BP1) directly, the expression of which was inversely correlated with the level of miR-625 in HCC cell lines and tissues. High expression of IGF2BP1 was frequently found in HCC samples, and associated with poor prognosis. Knockdown of endogenous IGF2BP1 by siRNA exhibited similar effects as the overexpression of miR-625, whereas overexpression of IGF2BP1 (without the 3'-UTR) abrogated miR-625-mediated metastasis inhibition. Interference of the PTEN/HSP27 pathway contributed to miR-625-mediated metastasis inhibition. Taken together, our data suggest that miR-625 might function as an antimetastatic miRNA to have an important role in HCC progression by modulating the IGF2BP1/PTEN pathway. The newly identified miR-625/IGF2BP1 axis represents a new potential therapeutic target for HCC treatment.
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61
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Chandiran AK, Abdi-Jalebi M, Yella A, Dar MI, Yi C, Shivashankar SA, Nazeeruddin MK, Grätzel M. Quantum-confined ZnO nanoshell photoanodes for mesoscopic solar cells. NANO LETTERS 2014; 14:1190-1195. [PMID: 24524200 DOI: 10.1021/nl4039955] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a photoanode for dye-sensitized solar cell (DSC) based on ZnO nanoshell deposited by atomic layer deposition at 150 °C on a mesoporous insulating template. An ultrathin layer of ZnO between 3 and 6 nm, which exhibits quantum confinement effect, is found to be sufficient to transport the photogenerated electrons to the external contacts and exhibits near-unity collection efficiency. A 6 nm ZnO nanoshell on a 2.5 μm mesoporous nanoparticle Al2O3 template yields photovoltaic power conversion efficiency (PCE) of 4.2% in liquid DSC. Perovskite absorber (CH3NH3PbI3) based solid state solar cells made with similar ZnO nanostructures lead to a high PCE of 7%.
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62
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Amacher A, Yi C, Yang J, Bircher MP, Fu Y, Cascella M, Grätzel M, Decurtins S, Liu SX. A quinoxaline-fused tetrathiafulvalene-based sensitizer for efficient dye-sensitized solar cells. Chem Commun (Camb) 2014; 50:6540-2. [DOI: 10.1039/c4cc02696a] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new strategy for the development of a compactly fused tetrathiafulvalene (TTF)-based sensitizer is reported, leading to the best performance to date for TTF-sensitized solar cells.
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63
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Lee S, Choi S, Min C, Park S, Jung H, Yi C, Yoo H, Kim M, Ji Y, Kim K. EP-1704: Evaluation of internal target volumes between 4D CT, Slow CT and CBCT according to breath patterns. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)31822-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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64
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Jiao XM, Zhang XG, Xu XUP, Yi C, Bin C, Cheng QP, Gong QQ, Lv XF. Blood glucose fluctuation aggravates lower extremity vascular disease in type 2 diabetes. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2014; 18:2025-2030. [PMID: 25027342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVES Lower-extremity vascular diseases are important complication of diabetes. In the present study, we investigated the influence of blood glucose fluctuation in type 2 diabetes-associated lower-extremity vascular diseases, and explore the possible mechanism. PATIENTS AND METHODS Patients with type 2 diabetes was assigned to Group B (without lower-extremity vascular disease) and group C (with lower-extremity vascular disease). Healthy subjects (Group A) served as normal controls. All patients received dynamic blood glucose monitoring for 72 h. The mean amplitude of glycemic excursion (MAGE) and the largest amplitude of glycemic excursion (LAGE) were estimated. The levels of von Willebrand factor (vWF), ischemia-modified albumin (IMA), glycosylated hemoglobin (HbA1c), and biochemical indices were examined, and the lower-extremity vascular diseases were scored in patients from group C. RESULTS Groups B and C have higher systolic blood pressure (SBP), total cholesterol (TC) level, high-density lipoprotein cholesterol (HDL-C) level, HbA1c level, and vWF level and lower IMA level than those in Group A (p < 0.05). Elevated MAGE and LAGE were observed in groups B and C as compared with Group A. Correlation analysis revealed that the score of lower-extremity vascular diseases was associated with MAGE, LAGE, SBP, LDL-C, vWF, HbA1c, and IMA (p < 0.05). Stepwise multiple-linear regression analysis revealed that lower-extremity vascular diseases were involved with MAGE, IMA, and vWF. CONCLUSIONS Enhanced fluctuation in patients with type 2 diabetes may promote the occurrence and development of lower-extremity vascular diseases through aggravating vascular endothelial injury.
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65
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Han S, Choi S, Park S, Jung H, Yi C, Yoo H, Kim M, Kim C, Ji Y, Kim K. EP-1451: Feasibility study of optical stimulated dosimeters for high dose evaluation in SBRT. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)31569-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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66
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Geng Y, Pop F, Yi C, Avarvari N, Grätzel M, Decurtins S, Liu SX. Electronic tuning effects via π-linkers in tetrathiafulvalene-based dyes. NEW J CHEM 2014. [DOI: 10.1039/c4nj00428k] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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67
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Li H, Schubert C, Dral PO, Costa RD, La Rosa A, Thüring J, Liu SX, Yi C, Filippone S, Martín N, Decurtins S, Clark T, Guldi DM. Inside Cover: Probing Charge Transfer in Benzodifuran-C 60
Dumbbell-Type Electron Donor-Acceptor Conjugates: Ground- and Excited-State Assays (ChemPhysChem 13/2013). Chemphyschem 2013. [DOI: 10.1002/cphc.201390062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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68
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Li H, Schubert C, Dral PO, Costa RD, La Rosa A, Thüring J, Liu SX, Yi C, Filippone S, Martín N, Decurtins S, Clark T, Guldi DM. Probing charge transfer in benzodifuran-C60 dumbbell-type electron donor-acceptor conjugates: ground- and excited-state assays. Chemphyschem 2013; 14:2910-9. [PMID: 23918655 DOI: 10.1002/cphc.201300378] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Indexed: 11/11/2022]
Abstract
Rigid electron donor-acceptor conjugates (1-3) that combine π-extended benzodifurans as electron donors and C60 molecules as electron acceptors with different linkers have been synthesized and investigated with respect to intramolecular charge-transfer events. Electrochemistry, fluorescence, and transient absorption measurements revealed tunable and structure-dependent charge-transfer processes in the ground and excited states. Our experimental findings are underpinned by density-functional theory calculations.
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69
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Han S, Kim K, Park S, Jung H, Lee S, Kim H, Yi C, Kim M, Ji Y. SU-E-T-38: The Evaluation of High Dose and Dosimetric Characteristics of Optical Stimulated Luminance Dosimeters in the 60CO Unit. Med Phys 2013. [DOI: 10.1118/1.4814473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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70
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Han S, Kim K, Park S, Lee S, Yi C, Kim H, Jung H, Kim M, Ji Y. SU-E-T-31: The Evaluation of Dosimetric Characteristics of OSLDs Based On Output Correction Factor in Low Energy. Med Phys 2013. [DOI: 10.1118/1.4814465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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71
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Lee S, Kim H, Han S, Kim M, Yoo H, Yi C, Park S, Jung H, Ji Y, Kim K. SU-E-T-711: Normal Tissue Tolerance Evaluation Tool for Clinical Protocols. Med Phys 2013. [DOI: 10.1118/1.4815138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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72
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Li H, Yi C, Moussi S, Liu SX, Daul C, Grätzel M, Decurtins S. Benzo[1,2-b:4,5-b′]difuran-based sensitizers for dye-sensitized solar cells. RSC Adv 2013. [DOI: 10.1039/c3ra43669a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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73
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Di W, Shi X, Zhu Y, Tao Y, Qi W, Luo N, Xiao Z, Yi C, Miao J, Zhang A, Zhang X, Fang Y. Overuse of paracetamol caffeine aspirin powders affects cerebral glucose metabolism in chronic migraine patients. Eur J Neurol 2012; 20:655-62. [PMID: 23114018 DOI: 10.1111/ene.12018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Accepted: 09/18/2012] [Indexed: 01/22/2023]
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74
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Grilj J, Todorova TK, Yi C, Liu SX, Vauthey E, Decurtins S. A Spectroscopic and Computational Study of a Photoinduced Cross-Dehydrogenative Coupling Reaction of a Stable Semiquinone Radical. Chemistry 2012; 18:13605-8. [DOI: 10.1002/chem.201201463] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/25/2012] [Indexed: 11/11/2022]
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75
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Chandiran AK, Tetreault N, Humphry-Baker R, Kessler F, Baranoff E, Yi C, Nazeeruddin MK, Grätzel M. Subnanometer Ga2O3 tunnelling layer by atomic layer deposition to achieve 1.1 V open-circuit potential in dye-sensitized solar cells. NANO LETTERS 2012; 12:3941-7. [PMID: 22681486 DOI: 10.1021/nl301023r] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Herein, we present the first use of a gallium oxide tunnelling layer to significantly reduce electron recombination in dye-sensitized solar cells (DSC). The subnanometer coating is achieved using atomic layer deposition (ALD) and leading to a new DSC record open-circuit potential of 1.1 V with state-of-the-art organic D-π-A sensitizer and cobalt redox mediator. After ALD of only a few angstroms of Ga(2)O(3), the electron back reaction is reduced by more than an order of magnitude, while charge collection efficiency and fill factor are increased by 30% and 15%, respectively. The photogenerated exciton separation processes of electron injection into the TiO(2) conduction band and the hole injection into the electrolyte are characterized in detail.
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