NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 7
·3111-3118
·
IF 3.069
Lulu Pan,Jianfeng Ban,Li Ren,Zuocai Zhang,Qingyuan Peng,Shaorong Lu
This paper aims at elucidating the influence of liquid crystals (LCs) on the properties of shape memory polymers. A novel series of liquid crystalline shape memory polyurethanes, named LC-SF-SMPUs were successfully prepared by chemically cross-linking polyester sisal fibre cellulose (PSF) with polycaprolactone (PCL) and 4,4′-di(6-hydroxyhexyloxy)biphenyl (BP6). The effect of BP6 on the morphology and properties has been carefully investigated. The results show that the cross-linking structures provided a stable network, high elasticity and good thermal stability to the LC-SF-SMPUs, and demonstrate that the obtained LC-SF-SMPUs not only maintained the LC property of BP6, but also enhanced the intrinsic crystallization of PCL. Thus, the LC-SF-SMPUs showed excellent multi-shape memory properties with two crystalline transition temperatures. In the triple-shape memory effect of LC-SF-SMPUs, the first step of strain recovery is associated with the melting transition of the soft segment crystals of the polyurethane matrix, and the second step of strain recovery results from the melting transition of the LC mesogen. The strain fixity improved with increasing BP6-content, due to the enhanced crystallinity. However, the total strain recovery decreased as a result of the lubrication of the BP6 chains. This work demonstrates a new combination of LC properties and multi-shape memory properties, which makes it ideal for many potential applications in new smart devices.
研究领域:
高分子材料
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智能材料
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功能高分子
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形状记忆聚合物
·
生物基材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Baifeng Wu,Xiaofeng Wang,Xuefeng Xia,Qixin Wan,Yangsheng Li,Fan Li
The power conversion efficiency (PCE) of the perovskite solar cell (PSC) has made an illustrious breakthrough in the past ten years. However, it is still a great challenge to fabricate high-quality perovskite films due to the intrinsic high defect-density and internal non-radiative recombination, which has severely hindered the development of PSCs . Herein, a new-type additive guanidinium tetrafluoroborate (GuaBF 4 ) is introduced to improve the perovskite films quality, thus boosting photovoltaic performance of resultant PSCs . It is demonstrated that owing to the synergistic effect of Gua + and BF 4 − , the introduction of GuaBF 4 can improve the quality of CH 3 NH 3 PbI 3 (MAPbI 3 ) films. Through optimizing the concentration of GuaBF 4 , the MAPbI 3 film with GuaBF 4 displays higher crystallinity , enlarged crystal grain and smoother surface. Furthermore, by virtue of the strong interaction between MAPbI 3 and GuaBF 4 , the inclusion of GuaBF 4 can effectively passivate traps/defects in perovskite films, thereby diminishing the non-radiative recombination and promoting the charge carrier transportation. Consequently, a high-performance MAPbI 3 PSC with a PCE of 20.62 %, lessened hysteresis behavior and improved moisture stability is achieved. Our research emphasizes on the significance of the synergistic effect in additives for high-performance PSCs.
研究领域:
材料科学
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能源科学
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半导体器件
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表面化学
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光电子学
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2016
·Vol. 18
·期 48
·32903-32909
·
IF 4.449
Fan Zhang,Jun Song,Ming Chen,Junchen Liu,Yuying Hao,Yuncai Wang,Junle Qu,Pengju Zeng
Organic–inorganic metal halide perovskites have led to remarkable advancements in emerging photovoltaics. The rapid increase in the power conversion efficiency (PCE) of PSCs has been mainly achieved by improving perovskite morphology and crystallinity. Herein, we report a simple and effective means to improve perovskite grain sizes using a porous hole transport layer (i.e., PEDOT:PSS in this work). We used polystyrene nanospheres as a sacrificial template to fabricate the porous-PEDOT:PSS. The growth of the CH3NH3PbI3 perovskite film on the porous-PEDOT:PSS substrate yields a dramatic improvement in crystallinity and an enhancement in perovskite grain sizes. When the porous structure was applied as a hole transport layer in PSCs with planar heterojunction structures, the efficiency was significantly enhanced from 15.33% for the planar device to 17.32%. This simple method for enhancing perovskite morphology and crystallinity paves the way for its application to other device architectures for enhanced photovoltaic performance.
研究领域:
材料科学
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光伏技术
·
纳米结构调控
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能源材料
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薄膜制备
✓ 已验证
DOI
高影响因子
ORGANIC ELECTRONICS
·
2019
·
IF 3.495
Xin Qi,Ganghong Liu,Duo Wang,Ning Zhu,Yuqing Zhang,Zehao Zhang,Cuncun Wu,Xiangdong Li,Wei Luo,Yingqiang Li,Haozhe Hu,Zhijian Chen,Lixin Xiao,Shufeng Wang,Bo Qu
Interfacial modification as a feasible strategy to improve the properties of perovskite solar cells (PSCs) has been widely studied in recent years. In this work, PbCl 2 modification at the interface of SnO 2 /CH 3 NH 3 PbI 3 was used for CH 3 NH 3 PbI 3 -based planar PSCs. The introduction of PbCl 2 between SnO 2 and CH 3 NH 3 PbI 3 layers boosted the crystallization of perovskite film, which promoted the photovoltaic properties of corresponding PSCs. The open circuit voltage ( V OC ) and fill factor (FF) of the PbCl 2 -modified devices (1 mg/mL) were 1.11 V and 0.79, respectively, which were both higher than those of the reference devices without PbCl 2 (1.04 V and 0.76). Moreover, a steady-state power output efficiency exceeding 19% was obtained for the PbCl 2 -modified devices (1 mg/mL), which implied that PbCl 2 modification was an effective and low cost strategy for efficient PSCs.
研究领域:
材料科学
·
光伏技术
·
纳米科技
·
表面与界面工程
·
能源材料
·
半导体器件
·
功能材料
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Le Li,Rui-Ying Bao,Tao Gao,Zheng-Ying Liu,Bang-Hu Xie,Ming-Bo Yang,Wei Yang
Improving the physical properties of biobased polymers using bionanofillers is essential to preserve its biodegradability. This work presents a dopamine-induced functionalization of cellulose nanocrystals (CNCs) with polyethylene glycol (PEG), to enhance the crystallization, mechanical and barrier properties of poly( L -lactic acid) (PLLA) bionanocomposites. The effect of molecular weight of grafted PEG on the properties of PLLA is also studied. PEGylation of CNCs significantly enhance the crystallization of PLLA, especially for CNCs functionalized with PEG of lower molecular weight, which lead to balanced strength and ductility, and 66.4% reduction in the oxygen permeability coefficient at a low content of 0.5 wt %. Moreover, 168% improvement of ductility for PLLA can be obtained by CNCs functionalized with longer PEG chains. The surface functionalization of CNCs proposed here opens up a green avenue towards designing and fabricating fully bio-based, high-barrier and low-cost polymer nanocomposites for packaging applications.
研究领域:
高分子材料
·
纳米复合材料
·
生物基包装
·
材料科学
·
聚合物改性
·
结晶动力学
✓ 已验证
DOI
高影响因子
Sustainable Energy & Fuels
·
2018
·Vol. 2
·期 10
·2154-2159
·
IF 0
Xing Guo,Bingjuan Zhang,Zhenhua Lin,Jie Su,Zhou Yang,Chunfu Zhang,Jingjing Chang,Shengzhong (Frank) Liu,Yue Hao
The electron/hole transport layer plays a very important role in the planar structure of perovskite solar cells. Conjugated polymers have received considerable attention for use in perovskite solar cells as hole/electron transport layers and passivation layers. Although the devices based on conjugated polymer hole transport layers have achieved much progress, their performance is still inferior to that of devices based on the conventional spiro-OMeTAD hole transport layer. Here, we investigated the solvent vapor annealing (SVA) effect on conjugated polymers as well as the corresponding perovskite solar cell devices. It was found that SVA treatment could enhance the hole charge carrier mobility and thin film crystallinity. Meanwhile, the charge transfer efficiency was enhanced, and charge recombination was reduced. Hence, the conjugated polymer based device exhibited comparable or even better performance compared with the conventional spiro-OMeTAD based device. Moreover, the device stability was also improved.
研究领域:
材料科学
·
光伏技术
·
纳米科技
·
表面与界面化学
·
凝聚态物理
·
能源材料
·
器件物理
✓ 已验证
DOI
危险品化学品经营许可证（带存储）