| 5 | 1/1 | 返回列表 |
| 查看: 777 | 回復(fù): 5 | ||
| 本帖產(chǎn)生 1 個 翻譯EPI ,點擊這里進(jìn)行查看 | ||
| 當(dāng)前只顯示滿足指定條件的回帖,點擊這里查看本話題的所有回帖 | ||
蓮花如夢木蟲之王 (文壇精英)
|
[求助]
求關(guān)于染料敏化太陽能電池的翻譯
|
|
|
Understanding electron-transfer (ET) processes in dye-sensitized solar cells (DSSCs) is crucial to improving their device performance. Recently, covalent attachment of dye molecules to mesoporous semiconductor nanoparticle films via molecular linkers has been employed to increase the stability of DSSC photoanodes. The power conversion efficiency (PCE) of these DSSCs, however, is lower than DSSCs with conventional unmodified photoanodes in this study. Ultrafast transient absorption pump–probe spectroscopy (TAPPS) has been used to study the electron injection process from N719 dye molecules to TiO2 nanoparticles (NPs) in DSSC photoanodes with and without the presence of two silane-based linker molecules: 3-aminopropyltriethoxysilane (APTES) and p-aminophenyltrimethoxysilane (APhS). Ultrafast biphasic electron injection kinetics were observed in all three photoanodes using a 530 nm pump wavelength and 860 nm probe wavelength. Both the slow and fast decay components, attributed to electron injection from singlet and triplet excited states, respectively, of the N719 dye to the TiO2 conduction band, are hindered by the molecular linkers. The hindering effect is less significant with the APhS linker than the APTES linker and is more significant for the singlet-state channel than the triplet-state one. Electron injection from the vibrationally excited states is less affected by the linkers. The spectroscopic results are interpreted on the basis of the standard ET theory and can be used to guide selection of molecular linkers for DSSCs with better device performance. Other factors that affect the efficiency and stability of the DSSCs are also discussed. The relatively lower PCE of the covalently attached photoanodes is attributed to the multilayer and aggregation of the dye molecules as well as the linkers. On the basis of the TAPPS measurements, we propose that the electron injection from the excited states of N719 dye to TiO2 semiconductor conduction band occurs via two channels: a fast channel (tens of femtoseconds) from the singlet states of N719 and a slow channel (~1−10 ps) from its triplet states. The electron injection process is hindered by linker molecules APTES and APhS that are covalently attached to the N719 dye molecules. The magnitude of the hindering effect depends on both the spin-multiplicity of the excited electronic states of the dye and molecular vibrations. The hindering effect is more significant for singlet excited-state molecules than molecules in triplet states. Electron injection from vibrationally excited triplet-state molecules is less vulnerable to the hindering effect. Electron injection processes in the FTO/TiO2/APhS/N719 photoanodes are faster than in the FTO/TiO2/APTES/N719 photoanode because the APhS molecule is more conductive due to its aromaticity. Suitable choice of linker molecules is therefore important in producing DSSCs that have both long stability and high PCE. The stability of the phtotoanodes is significantly increased upon covalent attachment, attributed to the protective environment provided by the linker molecules to the SCN ligands.9 Although the molecular linkers slow the electron injection process, it is still orders of magnitude faster than the charge recombination to dye molecules and the electrolyte as well. The relatively slower electron injection rate is therefore not the reason for the observed lower PCE of the FTO/TiO2/APTES/N719 photoanode compared with the conventional one. The relatively lower PCE of the covalently attached photoanodes is mainly due to the multilayer and aggregation of the dye molecules above the covalently bonded ones in addition to the possible multilayer formation of the linker itself. TAPPS results show that the FTO/TiO2/APhS/N719 photoanode has better coverage of monolayer dye molecules than the FTO/TiO2/APTES/N719 photoanode. A higher PCE is therefore expected. Monolayer coverage of linkers on semiconductor metal oxide is necessary for improving PCE of such devices, as shown recently.9 When the soaking time in dye solution was controlled to avoid multilayers, PCE of the FTO/ TiO2/APTES/N719 photoanode was increased to 6.0 ± 1.0%, very close to that of the conventional one (6.5 ± 0.9%). Modification of the covalently attached photoanodes, for instance, with gold nanoparticles, can further improve the performance of DSSCs with chemically functionalized photoanodes and will be the subject of future work. 專業(yè)性太強了,不知道怎么組織語言(想知道使用APhS 改性后優(yōu)異性能的具體體現(xiàn)) |
木蟲之王 (文壇精英)
木蟲之王 (文壇精英)
| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 284求調(diào)劑 +12 | junqihahaha 2026-03-26 | 13/650 |
|
|---|---|---|---|---|
|
[考研] 287求調(diào)劑 +11 | land xuxu 2026-03-26 | 11/550 |
|
|
[考研] 317分 一志愿南理工材料工程 本科湖工大 求調(diào)劑 +11 | 芋泥小鈴鐺 2026-03-28 | 11/550 |
|
|
[碩博家園] 求調(diào)劑 有機化學(xué)考研356分 +10 | Nadiums 2026-03-25 | 11/550 |
|
|
[有機交流] 考研調(diào)劑 +5 | watb 2026-03-26 | 5/250 |
|
|
[考研] 生物技術(shù)與工程 +7 | 1294608413 2026-03-25 | 8/400 |
|
|
[考研] 一志愿河北工業(yè)大學(xué)0817化工278分求調(diào)劑 +14 | jhybd 2026-03-23 | 19/950 |
|
|
[考研] 290求調(diào)劑 +3 | dfffsar 2026-03-29 | 3/150 |
|
|
[考博] 26申博自薦 +6 | whh869393 2026-03-24 | 6/300 |
|
|
[考研] 085600 材料與化工 329分求調(diào)劑 +14 | Mr. Z 2026-03-25 | 14/700 |
|
|
[考研] 332求92調(diào)劑 +8 | 蕉蕉123 2026-03-28 | 8/400 |
|
|
[考研] 298求調(diào)劑 +4 | 種圣賜 2026-03-28 | 4/200 |
|
|
[考研] 299求調(diào)劑 +7 | 嗯嗯嗯嗯2 2026-03-27 | 7/350 |
|
|
[考研] 070300求調(diào)劑306分 +4 | 26要上岸 2026-03-27 | 4/200 |
|
|
[考研] 藥學(xué)105500求調(diào)劑 +3 | Ssun。。 2026-03-28 | 3/150 |
|
|
[考研] 08開頭275求調(diào)劑 +4 | 拉誰不重要 2026-03-26 | 4/200 |
|
|
[考研] 081200-11408-276學(xué)碩求調(diào)劑 +4 | 崔wj 2026-03-26 | 4/200 |
|
|
[考研] 327求調(diào)劑 +7 | prayer13 2026-03-23 | 7/350 |
|
|
[考研] 0703化學(xué)求調(diào)劑 +3 | 丹青奶蓋 2026-03-26 | 5/250 |
|
|
[考研] 環(huán)境專碩324分求調(diào)劑推薦 +5 | 軒小寧—— 2026-03-26 | 5/250 |
|