Batteries & Supercaps
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2022
·Vol. 6
·期 3
·e202200480
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IF 6.043
Xiao Yang,Yi Zhao,Qiuju Xu,Xiangcheng Yuan,Jinzhang Liu
Graphical Quinone polymer ZIB cathode : Three different dihydroxynaphthalene (DHN) monomers are electrodeposited onto mesoporous activated carbon coatings to make cathodes for aqueous zinc-ion batteries. These polymer/carbon composite cathodes vary in terms of capacity and cycling stability, and key factors behind this divergence are investigated by combining experiment with theory. Organic cathode materials for aqueous rechargeable Zinc-ion batteries (ZIBs) include a large variety of aromatic molecules with redox-activity, and such polymer molecules vary largely in terms of specific capacity, discharge voltage plateau, and cycling stability. Here, three different quinone polymers are prepared by electropolymerizing dihydroxynaphthalene (DHN) isomers of 1,5-DHN, 1,6-DHN, and 1,7-DHN, respectively, and their energy storage performances in aqueous ZIBs are compared. Among the three cathode materials, the poly(1,6-DHN) cathode shows the best performance in specific capacity and cycling stability. The Zn||poly(1,6-DHN) cell shows a high areal capacity of 1.4 mAh cm −2 and a high capacity retention of 90 % after 5000 cycles. By combing experiment with computation, the HOMO level of the polymer molecule is found to play a key role behind the specific capacity. Using the poly(1,7-DHN) cathode that suffers from faster capacity decay in the cycling process, our investigation suggests that residual ions stuck between molecular chains in the insertion/deinsertion process account for the capacity loss. This study provides a further understanding of organic cathode materials for aqueous ZIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2016
·
IF 9.407
Wei Huang,Meilin Li,Luozheng Zhang,Tingbin Yang,Zhi Zhang,Hao Zeng,Xing Zhang,Li Dang,Yongye Liang
Recent advances in the power conversion efficiency (PCE) of polymer solar cells (PSCs) have demonstrated their potential for alternative photovoltaic technology. Besides photovoltaic performance, material cost and device fabrication process are among the key factors for practical applications. Herein, we report a facile molecular engineering approach with 4-methoxy modified thiophene as the conjugated side chain for polymer donors, which afforded lower highest occupied molecular orbital (HOMO) energy level and enhanced interchain interactions. Therefore, the corresponding PSCs exhibit enhanced open-circuit voltage and PCE compared with the counterparts with thiophene as the conjugated side chain. When fabricated from a nonhalogenated solvent without any additives, over 8% efficiency could be achieved in a representative polymer, PMOT5. Both the synthetic simplicity of materials and high performance from environmentally friendly solvent improve the accessibility of PSCs.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 47
·23955-23963
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IF 7.443
Jiaqi Cheng,Fengxian Xie,Yongsheng Liu,Wei E. I. Sha,Xinchen Li,Yang Yang,Wallace C. H. Choy
Hole transport layers (HTLs) with large work function (WF) tuning ability for good energy level alignment with deep highest occupied molecular orbital (HOMO) level donor materials are desirable for high-performance and high open-circuit voltage (VOC) organic solar cells (OSCs). Here, a novel low-temperature and solution-process approach to achieve WF tuning in HTLs is proposed. Specifically, the HTLs made from 2,3,4,5,6-pentafluorobenzylphosphonic acid (F5BnPA) incorporated graphene oxide (GO) and molybdenum oxide (MoOx) solution (representing two possible classes of HTLs where carriers transport via valence and conduction bands, respectively) offer continuous WF tuning (the tuning range as large as 0.81 eV) by controlling F5BnPA's concentration. By employing a deep HOMO donor material, OSCs using the composite HTLs can achieve improved performances with largely increased VOC (0.92 V for GO:F5BnPA versus 0.65 V for pristine GO; 0.91 V for MoOx:F5BnPA versus 0.88 V for pristine MoOx). The enhanced performance can be experimentally and theoretically explained by the decreased hole injection barrier (HIB) for GO or equivalent HIB (i.e. electron extraction barrier) for MoOx and enhanced surface recombination velocity, which contribute to eliminating S-shaped current–voltage characteristics. Consequently, the incorporation of F5BnPA can efficiently tune HTL WF for high VOC OSCs and extend HTL applications in organic electronics.
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Jiajun He,Yun Huang,Huihui Li,Jin Bao,Heguo Zeng,Zhanpeng Du,Fengliang Wang,Xiaoyan Ma,Xuepeng Zhong,Bo Yu,Xing Li,Mingshan Wang,Yuanhua Lin,Bingshu Guo,Haijun Cao
This study employs molecular engineering to modulate HOMO levels and electronic structures, designing high-performance phthalate-based anodes (ZnPA, CaPA, CuPA) to address challenges like limited capacity and poor cycling in organic lithium-ion batteries. CuPA delivers 749 mAh g −1 after 100 cycles at 0.1 A g −1 and retains 200 mAh g −1 after 2500 cycles at 1 A g −1 . ZnPA achieves 650 mAh g −1 at 0.1 A g −1 and maintains 200 mAh g −1 after 1500 cycles at 1 A g −1 . CaPA shows increased capacity at higher current (197 mAh g −1 at 1 A g −1 ) due to (100) plane expansion. Redox mechanisms differ: CuPA and ZnPA carbonyl group facilitates lithium storage by a reversible enolization reaction, while the activated benzene ring exhibits redox activity for reversible lithiation/delithiation, with Cu 2+ irreversibly reducing to Cu⁺, while Zn 2+ remains stable. CaPA enables efficient lithium storage by the reversible intercalation and deintercalation of lithium ions on its (100) crystallographic plane. Full cells with LiFePO 4 exhibit excellent performance: CuPA||LFP and ZnPA||LFP retain over 50% capacity after 1000 cycles; CaPA||LFP shows outstanding rate capability (103 mAh g −1 at 4C). This work demonstrates that molecular structural engineering is an effective strategy for enhancing organic electrode materials.
研究领域:
材料科学
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电化学
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能量存储
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电池技术
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分子工程
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产品关联
DOI
PubMed
高影响因子
Science China-Chemistry
·
2019
·Vol. 62
·期 6
·767-774
·
IF 6.085
Li Erpeng,Li Wenqin,Li Linchang,Zhang Hao,Shen Chao,Wu Zihua,Zhang Weiwei,Xu Xiaojia,Tian He,Zhu Wei-Hong,Wu Yongzhen
The development of p-i-n structured perovskite solar cells (PSCs) requires more extensive explorations on seeking efficient, low cost and stable hole transporting materials (HTMs). Small molecular HTMs are superior to polymeric ones in terms of synthetic reproducibility as well as purity. However, thin films composed of small molecules are usually labile during the solution-based perovskite deposition. Herein, we propose a molecular engineering strategy of incorporating oligothiophene as conjugation bridge to develop robust oligomer HTMs for p-i-n type PSCs. Upon increasing the oligothiophene chain length from α-bithiophene to α-quaterthiophene and α-hexathiophene, their HOMO energy levels remain unchanged, but their solubility in common organic solvents decreased remarkably, thus greatly enhancing their tolerance to the perovskite deposition. The rational design of oligothiophene chain length can effectively tune their optoelectronic properties as well as thin film stability under polar solvent soaking. The best performance is achieved by an α-quaterthiophene based HTM (QT), showing a high efficiency of 17.69% with fill factor of 0.81, which are comparable to those of a commercially available benchmark polymer HTM (poly[bis (4-phenyl)(2,4-dimethylphenyl) amine], PTAA) based devices fabricated under the same conditions. Our developed oligomer system not only provides the definite molecular structures like small molecule-type HTMs, but also exhibits the excellent film-forming like polymer-type HTMs, thus achieving the well-balanced parameters among solvent tolerance, thin film conductivity, and interfacial charge transfer efficiency, especially building up a platform to develop low cost and reproducible efficient HTMs in p-i-n structured perovskite solar cells.
研究领域:
材料科学
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太阳能
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有机电子学
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光伏技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）