Piezoelectric biomaterials have shown good energy conversion capability and promising future for biomedical applications.However,their performance is still limited by their relatively low piezoelectric constant,and in...Piezoelectric biomaterials have shown good energy conversion capability and promising future for biomedical applications.However,their performance is still limited by their relatively low piezoelectric constant,and in-creasing the power by connecting multiple devices is restricted by the challenge of synchronizing all individual devices.Herein,we develop double-layer FF peptide microrods arrays with independently controlled polarization in each layer.The resultant piezoelectric nanogenerator showed much enhanced performance because the syn-chronous deformation and the appropriate polarization directions of microrods in each individual layer enable the constructive contribution of voltage and current output from all microrods.The nanogenerator generated an open circuit voltage of 2.05 V in a serial connection mode,which doubles the output from a single-layer device.When two layers are connected in parallel and the polarization is in a head-to-head configuration,a twofold increase in the current output is also achieved.This work provides a new strategy to design integrated devices with much improved performance for wearable technology and therapeutic systems.展开更多
Developing dopant-free hole-transporting materials(HTMs)for high-performance perovskite solar cells(PVSCs)has been a very active research topic in recent years since HTMs play a critical role in optimizing interfacial...Developing dopant-free hole-transporting materials(HTMs)for high-performance perovskite solar cells(PVSCs)has been a very active research topic in recent years since HTMs play a critical role in optimizing interfacial charge carrier kinetics and in turn determining device performance.Here,a novel dendritic engineering strategy is first utilized to design HTMs with a D-A type molecular framework,and diphenylamine and/or carbazole is selected as the building block for constructing dendrons.All HTMs show good thermal stability and excellent film morphology,and the key optoelectronic properties could be fine-tuned by varying the dendron structure.Among them,MPA-Cz-BTI and MCz-Cz-BTI exhibit an improved interfacial contact with the perovskite active layer,and non-radiative recombination loss and charge transport loss can be effectively suppressed.Consequently,high power conversion efficiencies(PCEs)of 20.8%and 21.35%are achieved for MPA-Cz-BTI and MCz-Cz-BTI based devices,respectively,accompanied by excellent long-term storage stability.More encouragingly,ultrahigh fill factors of 85.2%and 83.5%are recorded for both devices,which are among the highest values reported to date.This work demonstrates the great potential of dendritic materials as a new type of dopant-free HTMs for high-performance PVSCs with excellent FF.展开更多
基金supported by the National Natural Science Founda-tion of China(52361145848,52192613,2204189)Ministry of Science and Technology of China(2022YFE0100800)+3 种基金Ministry of Science and Technology of Israel(3-18130)Natural Science Basic Research Plan in Shaanxi Province of China(2024GX-YBXM-514)Young Talent Fund of Association for Science and Technology in Shaanxi,China(20220115)Natural Science Foundation of Shaanxi Province(2019JCW-17 and 2020JCW-15).
文摘Piezoelectric biomaterials have shown good energy conversion capability and promising future for biomedical applications.However,their performance is still limited by their relatively low piezoelectric constant,and in-creasing the power by connecting multiple devices is restricted by the challenge of synchronizing all individual devices.Herein,we develop double-layer FF peptide microrods arrays with independently controlled polarization in each layer.The resultant piezoelectric nanogenerator showed much enhanced performance because the syn-chronous deformation and the appropriate polarization directions of microrods in each individual layer enable the constructive contribution of voltage and current output from all microrods.The nanogenerator generated an open circuit voltage of 2.05 V in a serial connection mode,which doubles the output from a single-layer device.When two layers are connected in parallel and the polarization is in a head-to-head configuration,a twofold increase in the current output is also achieved.This work provides a new strategy to design integrated devices with much improved performance for wearable technology and therapeutic systems.
基金the National Natural Science Foundation of China(21805128,21774055,61775091)Shenzhen Key Laboratory Project(ZDSYS201602261933302)+2 种基金Shenzhen Innovation Committee(JCYJ20180504165851864)Shenzhen Innovation Committee(JCYJ20170818141216288)the Seed Funding for Strategic Interdisciplinary Research Scheme of the University of Hong Kong。
文摘Developing dopant-free hole-transporting materials(HTMs)for high-performance perovskite solar cells(PVSCs)has been a very active research topic in recent years since HTMs play a critical role in optimizing interfacial charge carrier kinetics and in turn determining device performance.Here,a novel dendritic engineering strategy is first utilized to design HTMs with a D-A type molecular framework,and diphenylamine and/or carbazole is selected as the building block for constructing dendrons.All HTMs show good thermal stability and excellent film morphology,and the key optoelectronic properties could be fine-tuned by varying the dendron structure.Among them,MPA-Cz-BTI and MCz-Cz-BTI exhibit an improved interfacial contact with the perovskite active layer,and non-radiative recombination loss and charge transport loss can be effectively suppressed.Consequently,high power conversion efficiencies(PCEs)of 20.8%and 21.35%are achieved for MPA-Cz-BTI and MCz-Cz-BTI based devices,respectively,accompanied by excellent long-term storage stability.More encouragingly,ultrahigh fill factors of 85.2%and 83.5%are recorded for both devices,which are among the highest values reported to date.This work demonstrates the great potential of dendritic materials as a new type of dopant-free HTMs for high-performance PVSCs with excellent FF.
