Emerging quantum dots(QDs)based light-emitting field-effect transistors(QLEFETs)could generate light emission with high color purity and provide facile route to tune optoelectronic properties at a low fabrication cost...Emerging quantum dots(QDs)based light-emitting field-effect transistors(QLEFETs)could generate light emission with high color purity and provide facile route to tune optoelectronic properties at a low fabrication cost.Considerable efforts have been devoted to designing device structure and to understanding the underlying physics,yet the overall performance of QLEFETs remains low due to the charge/exciton loss at the interface and the large band offset of a QD layer with respect to the adjacent carrier transport layers.Here,we report highly efficient QLEFETs with an external quantum efficiency(EQE)of over 20%by employing a dielectric-QDs-dielectric(DQD)sandwich structure.Such DQD structure is used to control the carrier behavior by modulating energy band alignment,thus shifting the exciton recombination zone into the emissive layer.Also,enhanced radiative recombination is achieved by preventing the exciton loss due to presence of surface traps and the luminescence quenching induced by interfacial charge transfer.The DQD sandwiched design presents a new concept to improve the electroluminescence performance of QLEFETs,which can be transferred to other material systems and hence can facilitate exploitation of QDs in a new type of optoelectronic devices.展开更多
Glioblastoma multiforme is the most common and lethal brain tumour-type.The current standard of care includes Temozolomide(TMZ)chemotherapy.However,inherent and acquired resistance to TMZ thwart successful treatment.T...Glioblastoma multiforme is the most common and lethal brain tumour-type.The current standard of care includes Temozolomide(TMZ)chemotherapy.However,inherent and acquired resistance to TMZ thwart successful treatment.The direct repair protein methylguanine DNA methyltransferase(MGMT)removes the cytotoxic O6-methylguanine(O6-MeG)lesion delivered by TMZ and so its expression by tumours confers TMZ-resistance.DNA mismatch repair(MMR)is essential to process O6-MeG adducts and MMR-deficiency leads to tolerance of lesions,resistance to TMZ and further DNA mutations.In this article,two strategies to overcome TMZ resistance are discussed:(1)synthesis of imidazotetrazine analogues-designed to retain activity in the presence of MGMT or loss of MMR;(2)preparation of imidazotetrazine-nanoparticles to deliver TMZ preferably to the brain and tumour site.Our promising results encourage belief in a future where better prognoses exist for patients diagnosed with this devastating disease.展开更多
基金support from the National Natural Science Foundation of China(62174104,61735004,and 12174086)the National Key Research and Development Program of China(2016YFB0401702)the Shanghai Science and Technology Committee(19010500600)。
文摘Emerging quantum dots(QDs)based light-emitting field-effect transistors(QLEFETs)could generate light emission with high color purity and provide facile route to tune optoelectronic properties at a low fabrication cost.Considerable efforts have been devoted to designing device structure and to understanding the underlying physics,yet the overall performance of QLEFETs remains low due to the charge/exciton loss at the interface and the large band offset of a QD layer with respect to the adjacent carrier transport layers.Here,we report highly efficient QLEFETs with an external quantum efficiency(EQE)of over 20%by employing a dielectric-QDs-dielectric(DQD)sandwich structure.Such DQD structure is used to control the carrier behavior by modulating energy band alignment,thus shifting the exciton recombination zone into the emissive layer.Also,enhanced radiative recombination is achieved by preventing the exciton loss due to presence of surface traps and the luminescence quenching induced by interfacial charge transfer.The DQD sandwiched design presents a new concept to improve the electroluminescence performance of QLEFETs,which can be transferred to other material systems and hence can facilitate exploitation of QDs in a new type of optoelectronic devices.
基金This studentship is supported by the Engineering and Physical Sciences Research Council(EP/L01646X).
文摘Glioblastoma multiforme is the most common and lethal brain tumour-type.The current standard of care includes Temozolomide(TMZ)chemotherapy.However,inherent and acquired resistance to TMZ thwart successful treatment.The direct repair protein methylguanine DNA methyltransferase(MGMT)removes the cytotoxic O6-methylguanine(O6-MeG)lesion delivered by TMZ and so its expression by tumours confers TMZ-resistance.DNA mismatch repair(MMR)is essential to process O6-MeG adducts and MMR-deficiency leads to tolerance of lesions,resistance to TMZ and further DNA mutations.In this article,two strategies to overcome TMZ resistance are discussed:(1)synthesis of imidazotetrazine analogues-designed to retain activity in the presence of MGMT or loss of MMR;(2)preparation of imidazotetrazine-nanoparticles to deliver TMZ preferably to the brain and tumour site.Our promising results encourage belief in a future where better prognoses exist for patients diagnosed with this devastating disease.
