Fluorescent probes based on intramolecular charge transfer(ICT) have obvious advantages for accurate quantitative analysis.To obtain high-performance ratiometric probes requires distinct photophysical properties durin...Fluorescent probes based on intramolecular charge transfer(ICT) have obvious advantages for accurate quantitative analysis.To obtain high-performance ratiometric probes requires distinct photophysical properties during recognition reaction process,which is closely related to their ICT characteristics.1,8-Naphthalimide is known as a typical fluorophore with desirable ICT property when functionalized with an electron-donating moiety at the para-position of the naphthalene chromophore.Although the photophysical properties of para-substituted 1,8-naphthalimide have been well studied,its meta-substituted counterpart has not been fully evaluated since the meta-position is conventionally thought to be weakly conjugated.Herein,combined experimental and theoretical studies are performed which consistently indicate that stronger charge transfer(CT) is exhibited by the meta-amino substituted 1,8-naphthalimide(m-NH_(2)) compared to the para-amino substituted one(p-NH_(2)).The ratiometric response of fluorescence with significant changes in wavelength and intensity upon acetylation(m-NAc and p-NAc) can be attributed to the larger ICT and stronger-NH_(2) vibrations.This observation is further demonstrated by deuterium oxide experiments,viscosity experiments and quantum chemical calculations.The practical application of meta-amino-1,8-naphthalimide ICT-based probes is also confirmed.This research is expected to bring an in-depth understanding of π-conjugated systems with ICT characteristics,and facilitates the design of sensitive ICT fluorescent probes with meta-amino substitution.展开更多
Regulating the interfacial charge transfer is pivotal for elucidating the kinetics of engineering the interface between the light-harvesting semiconductor and the substrate/catalyst for photoelectrocatalytic water spl...Regulating the interfacial charge transfer is pivotal for elucidating the kinetics of engineering the interface between the light-harvesting semiconductor and the substrate/catalyst for photoelectrocatalytic water splitting.In this study,we constructed a superior Ti-doped hematite photoanode(TiFeO)by employing SnOx as an electron transfer mediator,partially oxidized graphene(pGO)as a hole transfer mediator,and molecular Co cubane as a water oxidation catalyst.The Co/pGO/TiFeO/SnO_(x)integrated system achieves a photocurrent density of 2.52 mA cm^(-2) at 1.23 VRHE,which is 2.4 times higher than bare photoanode(1.04 mA cm^(-2)),with operational stability up to 100 h.Kinetic measurements indicate that pGO can promote charge transfer from TiFeO to the Co cubane catalyst.In contrast,SnOx reduces charge recombination at the interface between TiFeO and the fluorinated tin oxide substrate.In-situ infrared spectroscopy shows the formation of an O–O bonded intermediate during water oxidation.This study highlights the crucial role of incorporating dual charge-transfer mediators into photoelectrodes for efficient solar energy conversion.展开更多
Realizing efficient and controlled state transfers is necessary for implementing a wide range of classical and quantum information protocols.Recent studies have demonstrated that both asymmetric and symmetric state tr...Realizing efficient and controlled state transfers is necessary for implementing a wide range of classical and quantum information protocols.Recent studies have demonstrated that both asymmetric and symmetric state transfers can be achieved by encircling an exceptional point(EP)in non-Hermitian(NH)systems.However,the application of this phenomenon has been restricted to scenarios where an EP exists in single-qubit systems and is associated with a specific type of dissipation.In this work,we demonstrate efficient and controlled symmetric and asymmetric Bell-state transfers by modulating system parameters within a Jaynes-Cummings model while accounting for atomic spontaneous emission and cavity decay.The effective suppression of nonadiabatic transitions enables a symmetric exchange of Bell states irrespective of the encircling direction.Furthermore,we report a counterintuitive finding:the presence of an EP is not indispensable for implementing asymmetric state transfers in NH systems.We achieve perfect asymmetric Bell-state transfers even in the absence of an EP by dynamically orbiting around an approximate EP.Our work presents an approach to effectively and reliably manipulate entangled states with both symmetric and asymmetric characteristics,through dissipation engineering in NH systems.展开更多
基金financially supported by National Key Research and Development Programs (Nos.2022YFD1700403 and 2023YFD1700303)National Natural Science Foundation of China (Nos.12274128 and 12250003)+2 种基金Shanghai Rising-Star Program (No.21QA1402600)the support of NYU-ECNU Center for Computational Chemistry at NYU Shanghaithe University of Bath and the Open Research Fund of the School of Chemistry and Chemical Engineering,Henan Normal University (No.2020ZD01) for support。
文摘Fluorescent probes based on intramolecular charge transfer(ICT) have obvious advantages for accurate quantitative analysis.To obtain high-performance ratiometric probes requires distinct photophysical properties during recognition reaction process,which is closely related to their ICT characteristics.1,8-Naphthalimide is known as a typical fluorophore with desirable ICT property when functionalized with an electron-donating moiety at the para-position of the naphthalene chromophore.Although the photophysical properties of para-substituted 1,8-naphthalimide have been well studied,its meta-substituted counterpart has not been fully evaluated since the meta-position is conventionally thought to be weakly conjugated.Herein,combined experimental and theoretical studies are performed which consistently indicate that stronger charge transfer(CT) is exhibited by the meta-amino substituted 1,8-naphthalimide(m-NH_(2)) compared to the para-amino substituted one(p-NH_(2)).The ratiometric response of fluorescence with significant changes in wavelength and intensity upon acetylation(m-NAc and p-NAc) can be attributed to the larger ICT and stronger-NH_(2) vibrations.This observation is further demonstrated by deuterium oxide experiments,viscosity experiments and quantum chemical calculations.The practical application of meta-amino-1,8-naphthalimide ICT-based probes is also confirmed.This research is expected to bring an in-depth understanding of π-conjugated systems with ICT characteristics,and facilitates the design of sensitive ICT fluorescent probes with meta-amino substitution.
文摘Regulating the interfacial charge transfer is pivotal for elucidating the kinetics of engineering the interface between the light-harvesting semiconductor and the substrate/catalyst for photoelectrocatalytic water splitting.In this study,we constructed a superior Ti-doped hematite photoanode(TiFeO)by employing SnOx as an electron transfer mediator,partially oxidized graphene(pGO)as a hole transfer mediator,and molecular Co cubane as a water oxidation catalyst.The Co/pGO/TiFeO/SnO_(x)integrated system achieves a photocurrent density of 2.52 mA cm^(-2) at 1.23 VRHE,which is 2.4 times higher than bare photoanode(1.04 mA cm^(-2)),with operational stability up to 100 h.Kinetic measurements indicate that pGO can promote charge transfer from TiFeO to the Co cubane catalyst.In contrast,SnOx reduces charge recombination at the interface between TiFeO and the fluorinated tin oxide substrate.In-situ infrared spectroscopy shows the formation of an O–O bonded intermediate during water oxidation.This study highlights the crucial role of incorporating dual charge-transfer mediators into photoelectrodes for efficient solar energy conversion.
基金supported by the National Key Research and Development Program of China(Grant No.2024YFA1408900)the National Natural Science Foundation of China(Grant Nos.12264040,12374333,and U21A20436)+2 种基金the Jiangxi Natural Science Foundation(Grant Nos.20232BCJ23022 and 20252BAC240119)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301705)the Jiangxi Province Key Laboratory of Applied Optical Technology(Grant No.2024SSY03051)。
文摘Realizing efficient and controlled state transfers is necessary for implementing a wide range of classical and quantum information protocols.Recent studies have demonstrated that both asymmetric and symmetric state transfers can be achieved by encircling an exceptional point(EP)in non-Hermitian(NH)systems.However,the application of this phenomenon has been restricted to scenarios where an EP exists in single-qubit systems and is associated with a specific type of dissipation.In this work,we demonstrate efficient and controlled symmetric and asymmetric Bell-state transfers by modulating system parameters within a Jaynes-Cummings model while accounting for atomic spontaneous emission and cavity decay.The effective suppression of nonadiabatic transitions enables a symmetric exchange of Bell states irrespective of the encircling direction.Furthermore,we report a counterintuitive finding:the presence of an EP is not indispensable for implementing asymmetric state transfers in NH systems.We achieve perfect asymmetric Bell-state transfers even in the absence of an EP by dynamically orbiting around an approximate EP.Our work presents an approach to effectively and reliably manipulate entangled states with both symmetric and asymmetric characteristics,through dissipation engineering in NH systems.
