Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites.However,their incomplete passivation and chaotic usage amounts are not conducive to the preparation of highq...Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites.However,their incomplete passivation and chaotic usage amounts are not conducive to the preparation of highquality perovskite films.Herein,we succeeded in obtaining higher-quality CsPbBr_(3)films by introducing large-area monolayer graphene as a stable physical overlay on top of TiO_(2)substrates.Benefiting from the inert and atomic smooth graphene surface,the CsPbBr_(3)film grown on top by the van der Waal epitaxy has higher crystallinity,improved(100)orientation,and an average domain size of up to 1.22μm.Meanwhile,a strong downward band bending is observed at the graphene/perovskite interface,improving the electron extraction to the electron transport layers(ETL).As a result,perovskite film grown on graphene has lower photoluminescence(PL)intensity,shorter carrier lifetime,and fewer defects.Finally,a photovoltaic device based on epitaxy CsPbBr_(3)film is fabricated,exhibiting power conversion efficiency(PCE)of up to 10.64%and stability over 2000 h in the air.展开更多
Red emissive carbon dots(CDs)are highly desired for biological applications.However,serious luminescence quenching of red emissive CDs in aqueous solution greatly hinders their application in high performance biologic...Red emissive carbon dots(CDs)are highly desired for biological applications.However,serious luminescence quenching of red emissive CDs in aqueous solution greatly hinders their application in high performance biological imaging.Herein,we reported a facile strategy to realize enhanced red emission of CDs in aqueous solution by surface modification with polyetherimide(PEI)via microwave heating method.High photoluminescence quantum yield(PLQY)of 25%was realized from the PEI functionalized CDs(CDs@PEI)in aqueous solution.The proposed PEI functionalization strategy not only protects the red emission against water molecules quenching,but also reverses the surface charges from negativity to positivity to promote cellular uptake of CDs,leading to clear cell imaging in red fluorescence region.More important,CDs@PEI exhibits much better photostability than commercial red emissive dye(MitoT racker red)in cell fluorescent imaging.Potential application of CDs@PEI on fast staining of cells for clonogenic assay has also been demonstrated.展开更多
The poor cycling stability of graphite in traditional ester electrolyte limits its applications as anodes for potassium ion batteries(KIBs).Herein,we demonstrate that the introduction of cyclic ether co-solvents into ...The poor cycling stability of graphite in traditional ester electrolyte limits its applications as anodes for potassium ion batteries(KIBs).Herein,we demonstrate that the introduction of cyclic ether co-solvents into ester electrolytes can remarkably enhance the cycling stability of graphite anodes.The graphite anode in ester electrolyte with cyclic ether could achieve a reversible capacity of 196.1 m Ah g^(-1) after 100 cycles at 0.3 C(1 C=280 m A g^(-1)),about three times higher than those in ester electrolytes with or without linear ether.Compared with the SEI formed in ester electrolytes,the addition of tetrahydrofuran promotes the generation of K_(2)CO_(3) and ethylene oxide oligomers(PEO),of which the K_(2)CO_(3) is expected to be more conductive and PEO is mechanically robust.The more uniform,conductive and stable solid electrolyte interphases(SEIs)on graphite in electrolytes with cyclic ethers contribute to the enhancement of the electrochemical performances of graphite.This work provides a novel design of commercialized electrolytes to achieve high-performance anodes for KIBs,which potentially accelerates the development of KIBs.展开更多
Carbon dots(CDs)with long-wavelength absorptions and emissions are highly desired for biological applications.Herein,we report a new supra-CDs strategy to construct long-wavelength absorption bands based on fused CDs ...Carbon dots(CDs)with long-wavelength absorptions and emissions are highly desired for biological applications.Herein,we report a new supra-CDs strategy to construct long-wavelength absorption bands based on fused CDs aggregates(f-CDAs)through a concentration-induced interparticle dehydration process among green emissive CDs(r-CDs)under solvothermal treatment.The obtained fused f-CDAs exhibit an obvious absorption band in 550-700 nm and significantly enhanced deep red fluorescence in N,N-dimethylformamide with photoluminescence quantum yields of 15.6% and high photothermal conversion efficiency up to 26.1%in water.Benefiting from the high photothermal performance,in vivo tumor photothermal therapy has been realized via intratumoral injection of f-CDAs under 655 nm laser irradiated at 0.5 W/cm^(2).展开更多
基金funded by the UM’s research funds(MYRG2020-00283-IAPME,MYRG2022-00266-IAPME,and MYRG-GRG2023-00224-IAPME-UMDF)the Science and Technology Development Fund,Macao SAR(FDCT 0006/2021/AKP,FDCT 0096/2020/A2,0013/2021/AMJ,and 0082/2022/A2)City University of Hong Kong(Project No.9020002)
文摘Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites.However,their incomplete passivation and chaotic usage amounts are not conducive to the preparation of highquality perovskite films.Herein,we succeeded in obtaining higher-quality CsPbBr_(3)films by introducing large-area monolayer graphene as a stable physical overlay on top of TiO_(2)substrates.Benefiting from the inert and atomic smooth graphene surface,the CsPbBr_(3)film grown on top by the van der Waal epitaxy has higher crystallinity,improved(100)orientation,and an average domain size of up to 1.22μm.Meanwhile,a strong downward band bending is observed at the graphene/perovskite interface,improving the electron extraction to the electron transport layers(ETL).As a result,perovskite film grown on graphene has lower photoluminescence(PL)intensity,shorter carrier lifetime,and fewer defects.Finally,a photovoltaic device based on epitaxy CsPbBr_(3)film is fabricated,exhibiting power conversion efficiency(PCE)of up to 10.64%and stability over 2000 h in the air.
基金supported by the National Natural Science Foundation of China(No.61922091)the Science and Technology Development Fund of Macao SAR(Nos.0040/2019/A1,0073/2019/AMJ,0128/2020/A3 and 0131/2020/A3)University of Macao(Nos.SRG2019-00163-IAPME,MYRG2019-00103-IAPME)。
文摘Red emissive carbon dots(CDs)are highly desired for biological applications.However,serious luminescence quenching of red emissive CDs in aqueous solution greatly hinders their application in high performance biological imaging.Herein,we reported a facile strategy to realize enhanced red emission of CDs in aqueous solution by surface modification with polyetherimide(PEI)via microwave heating method.High photoluminescence quantum yield(PLQY)of 25%was realized from the PEI functionalized CDs(CDs@PEI)in aqueous solution.The proposed PEI functionalization strategy not only protects the red emission against water molecules quenching,but also reverses the surface charges from negativity to positivity to promote cellular uptake of CDs,leading to clear cell imaging in red fluorescence region.More important,CDs@PEI exhibits much better photostability than commercial red emissive dye(MitoT racker red)in cell fluorescent imaging.Potential application of CDs@PEI on fast staining of cells for clonogenic assay has also been demonstrated.
基金financially supported by the National Natural Science Foundation of China(U21A2081,22075074,22179014)the Outstanding Young Scientists Research Funds from Hunan Province(2020JJ2004)+2 种基金the Major Science and Technology Program of Hunan Province(2020WK2013)the Natural Science Foundation of Hunan Province(2021JJ40047)the State Key Laboratory of Materials Processing and Die&Mould Technology,Huazhong University of Science and Technology(P2022-020)。
文摘The poor cycling stability of graphite in traditional ester electrolyte limits its applications as anodes for potassium ion batteries(KIBs).Herein,we demonstrate that the introduction of cyclic ether co-solvents into ester electrolytes can remarkably enhance the cycling stability of graphite anodes.The graphite anode in ester electrolyte with cyclic ether could achieve a reversible capacity of 196.1 m Ah g^(-1) after 100 cycles at 0.3 C(1 C=280 m A g^(-1)),about three times higher than those in ester electrolytes with or without linear ether.Compared with the SEI formed in ester electrolytes,the addition of tetrahydrofuran promotes the generation of K_(2)CO_(3) and ethylene oxide oligomers(PEO),of which the K_(2)CO_(3) is expected to be more conductive and PEO is mechanically robust.The more uniform,conductive and stable solid electrolyte interphases(SEIs)on graphite in electrolytes with cyclic ethers contribute to the enhancement of the electrochemical performances of graphite.This work provides a novel design of commercialized electrolytes to achieve high-performance anodes for KIBs,which potentially accelerates the development of KIBs.
基金National Natural Science Foundation of China,Grant/Award Number:61922091science and technology development fund of Macao SAR,Grant/Award Numbers:0040/2019/A1,0073/2019/AMJ,0011/2019/AKP,0128/2020/A3,0131/2020/A3University of Macao,Grant/Award Numbers:CPG2020-00026-IAPME,MYRG2019-00103-IAPME。
文摘Carbon dots(CDs)with long-wavelength absorptions and emissions are highly desired for biological applications.Herein,we report a new supra-CDs strategy to construct long-wavelength absorption bands based on fused CDs aggregates(f-CDAs)through a concentration-induced interparticle dehydration process among green emissive CDs(r-CDs)under solvothermal treatment.The obtained fused f-CDAs exhibit an obvious absorption band in 550-700 nm and significantly enhanced deep red fluorescence in N,N-dimethylformamide with photoluminescence quantum yields of 15.6% and high photothermal conversion efficiency up to 26.1%in water.Benefiting from the high photothermal performance,in vivo tumor photothermal therapy has been realized via intratumoral injection of f-CDAs under 655 nm laser irradiated at 0.5 W/cm^(2).