Chiral organic-inorganic hybrid metal halides(OIHMHs)have attracted broader scientific community recently in spin lightemitting diodes,and circularly polarized light-emitting diodes.However,the emission peaks of the r...Chiral organic-inorganic hybrid metal halides(OIHMHs)have attracted broader scientific community recently in spin lightemitting diodes,and circularly polarized light-emitting diodes.However,the emission peaks of the reported chiral OIHMHs mainly locate in the visible region,and chiral OIHMH with ultraviolet(UV)circularly polarized luminescence(CPL)has been rarely reported.To fill this gap,cerium,a unique rare-earth(RE)element with tunable luminescence from UV to the visible region owing to the 4 f-related electronic transition,was introduced to construct the first RE-based chiral OIHMHs,R/S-MCC.The chirality is successfully transferred from the chiral organic cations to the inorganic cerium chloride framework in R/S-MCC,as confirmed by the single crystal structures,circular dichroism,and CPL.The emission spectra of R/S-MCC are in the UV region,originating from the characteristic d-f transition of Ce^(3+),which making the Ce-based metal halides are ideal candidates towards CPL light sources in the UV region.Notably,R-and S-MCC are the first RE-based OIHMHs,also the first chiral metalhalides with UV CPL.Our work opens a new avenue for the development of the chiral OIHMH family towards RE-based chiral OIHMH.The RE-based chiral metal halides couple the unique and superior optical,electrical,magnetic,and spintronic properties of RE elements with chirality could accelerate the development of chiral optoelectronics and spintronics toward real applications.展开更多
Dimerized small-molecule acceptors(SMAs) built by the conventional connection of terminal groups of monomers have contributed to exciting long-term stabilities of organic solar cells(OSCs). However, device efficiencie...Dimerized small-molecule acceptors(SMAs) built by the conventional connection of terminal groups of monomers have contributed to exciting long-term stabilities of organic solar cells(OSCs). However, device efficiencies, especially fill factors(FFs), still need to be improved. This probably originates from unsymmetrical molecular structure/conformation-determined less compact/ordered molecular stackings, such as ineffective stackings of constraint terminals. Herein, an exotic dimerized SMA of BC-Th is established by bridging the branched groups(BC-type, branch coupling) of two monomers rather than conventional terminal units(TC-type, terminal coupling). Benefiting from the three-dimensional conformation and more uncurbed terminals,BC-Th exhibits multiple molecular orientations along with a larger dielectric constant and electron mobility compared with TCTh. Finally, an efficiency of 17.43% is achieved by BC-Th-based OSCs, along with the highest FF of 79.13% among all dimerized SMAs-based OSCs to date. When introducing L8-BO as the third component, overall enhanced efficiency of 18.05%and FF of 80.11% are further afforded. Contrarily, TC-Th-based OSCs exhibit much inferior PCE of 16.29% and FF of 74.81%,demonstrating the great advantages of “branch coupling” over “terminal coupling” when building dimerized SMAs.展开更多
Tailoring the nanostructure and composition of transition metal nitrides is highly important for their use as potent low-cost electrocatalysts. Cobalt nitride(CoN) exhibits strong catalytic activity for oxygen evoluti...Tailoring the nanostructure and composition of transition metal nitrides is highly important for their use as potent low-cost electrocatalysts. Cobalt nitride(CoN) exhibits strong catalytic activity for oxygen evolution reaction(OER). However, its poor catalytic efficiency for oxygen reduction reaction(ORR) hinders its application in rechargeable zinc-air batteries(ZABs) as the air cathode. In this work, we deploy the effective strategy of Mn doping to improve both OER and ORR activity of CoN nanowires as the cathode material for ZAB. Theoretical calculation predicts that moderate Mn doping in cobalt nitride results in a downshift of the d-band center and reduces the adsorption energy of reaction intermediates. With ~10 at% Mn dopants, stronger catalysis activities for both OER and ORR are achieved compared to pure CoN nanowires. Subsequently, both aqueous and flexible quasi-solid-state ZABs are constructed using the Mn-doped CoN nanowires array as additive-free air cathode. Both types of devices present large open circuit potential, high power density and long-cycle stability. This work pushes forward the progress in developing cost-effective ZABs.展开更多
Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.Ho...Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.However,the traditionally used preparation methods with a long period and limited product yield have curtailed the commercialization of these materials.Here we introduce a universal hydrochloric acid-assistant powder-to-powder strategy which can accomplish the goals of thermal-,pressure-free,eco-friendliness,short time,low cost and high product yield,simultaneously.The obtained Cs_(2)Na_(0.9)Ag_(0.1)In_(0.95)Bi_(0.05)Cl_(6)microcrystals exhibit bright self-trapped excitons emission with quantum yield of(98.3±3.8)%,which could retain(90.5±1.3)%and(96.8±0.8)%after continuous heating or ultraviolet-irradiation for 1000 h,respectively.The phosphor converted-LED exhibited near-unity conversion efficiency from ultraviolet chip to self-trapped excitons emission at~200 mA.Various ions doping(such as Cs_(2)Na_(0.9)Ag_(0.1)InCl_(6):Ln^(3+))and other derived lead-free perovskite materials(such as Cs_(2)ZrCl_(6)and Cs_(4)MnBi_(2)Cl_(12))with high luminous performance are all realized by our proposed strategy,which has shown excellent availability towards commercialization.展开更多
All-small organic solar cells(ASM OSCs)inherit the advantages of the distinct merits of small molecules,such as well-defined structures and less batch-to-batch variation.In comparison with the rapid development of pol...All-small organic solar cells(ASM OSCs)inherit the advantages of the distinct merits of small molecules,such as well-defined structures and less batch-to-batch variation.In comparison with the rapid development of polymer-based OSCs,more efforts are needed to devote to improving the performance of ASM OSCs to close the performance gap between ASM and polymer-based OSCs.Herein,a well-known p-dopant named fluoro-7,7,8,8-tetracyano-p-quinodimethane(FTCNQ)was introduced to a highefficiency system of HD-1:BTP-e C9,and a high power conversion efficiency(PCE)of 17.15%was achieved due to the improved electrical properties as well as better morphology of the active layer,supported by the observed higher fill factor(FF)of 79.45%and suppressed non-radiative recombination loss.Furthermore,combining with the further morphology optimization from solvent additive of 1-iodonaphthalene(IN)in the blend film,the HD-1:BTP-e C9-based device with the synergistic effects of both FTCNQ and IN demonstrates a remarkable PCE of 17.73%(certified as 17.49%),representing the best result of binary ASM OSCs to date.展开更多
The central unit(benzo[c][1,2,5]thiadiazole) in Y6 series of molecules plays a determining role in their unique intermolecular packing for a three-dimensionally(3D) network, largely endowing their organic solar cells(...The central unit(benzo[c][1,2,5]thiadiazole) in Y6 series of molecules plays a determining role in their unique intermolecular packing for a three-dimensionally(3D) network, largely endowing their organic solar cells(OSCs) with so far the best power conversion efficiencies(PCEs) and also largely suppressed energy losses(Eloss). Despite its vital role in molecular packing, very few explorations for central unit have been conducted due to possibly the constructing challenge of central heterocyclic units.Herein, a highly efficient acceptor-donor-acceptor(A-D-A) type electron acceptor, CH17, has been designed and constructed,featured with a prominent π extension in both directions of the central and end units with respect to Y6 series. Such a multiple and much enhanced conjugation extension in CH17 enables a much more effective and compact 3D molecular packing compared with that of Y6 supported by X-ray single crystal and other analysis, mainly caused by a newly observed distinctive dual “end unit to central unit” packing mode. This much favorable molecular packing, also kept in its blends with donor materials, leads a larger electron and hole transfer integrals and hence much improved charge transport, and reduced energetic disorders in CH17blends. More importantly, the observed upshifted charge transfer(CT) state of CH17 blends compared with that of Y6, due to its increased molecular conjugation extension in both directions, further enhances the hybridization between its CT and local exciton(LE) states, resulting in higher luminescence efficiency, much suppressed non-radiative recombination loss and smaller Elosswith respect to that of Y6. Consequently, an excellent PCE of 17.84% is achieved with PM6 as the donor in a binary device compared with a PCE of 16.27% for the controlled Y6 device. Furthermore, a further improved PCE of 18.13% is achieved by CH17-based ternary single-junction OSCs along with a markedly reduced Elossof 0.49 e V and larger open-circuit voltage(Voc) of0.89 V, compared with that(16.27% of PCE, 0.85 V of Voc, and 0.53 e V of Eloss) of the control device using Y6. This significantly improved photovoltaic performance caused by molecular multiple conjugation extension, especially through the largely unexplored central unit, indicates that there is still much room to further enhance OSC performance by addressing the most important issue for OSC, i.e, the smaller Voccaused by larger Eloss, through engineering molecular packing by designing/tuning molecule more dedicatedly.展开更多
The possible practical limits for the specific surface area and capacitance performance of bulk sp^2 carbon materials were investigated experimentally and theoretically using a variety of carbon materials. We find the...The possible practical limits for the specific surface area and capacitance performance of bulk sp^2 carbon materials were investigated experimentally and theoretically using a variety of carbon materials. We find the limit for the specific surface area to be 3500–3700 m^2 g^(-1), and based on this, the corresponding best capacitance was predicted for various electrolyte systems. A model using an effective ionic diameter for the electrolyte ions was proposed and used to calculate the theoretical capacitance. A linear dependence of experimental capacitance versus effective specific surface area of various sp^2 carbon materials was obtained for all studied ionic liquid, organic and aqueous electrolyte systems. Furthermore, excellent agreement between the theoretical and experimental capacitance was observed for all the tested sp^2 carbon materials in these electrolyte systems, indicating that this model can be applied widely in the evaluation of various carbon materials for supercapacitors.展开更多
基金supported by the National Natural Science Foundation of China(92256202,12261131500,22305129,22371131,52103218)the Fundamental Research Funds for the Central Universities,Nankai University(023-63223021)+3 种基金Tianjin Key Lab for Rare Earth Materials and Applications(ZB19500202)the Outstanding Youth Project of Tianjin Natural Science Foundation(20JCJQJC00130)China Postdoctoral Science Foundation(BX20220157,2022M721698)the 111 Project(B12015,B18030)。
文摘Chiral organic-inorganic hybrid metal halides(OIHMHs)have attracted broader scientific community recently in spin lightemitting diodes,and circularly polarized light-emitting diodes.However,the emission peaks of the reported chiral OIHMHs mainly locate in the visible region,and chiral OIHMH with ultraviolet(UV)circularly polarized luminescence(CPL)has been rarely reported.To fill this gap,cerium,a unique rare-earth(RE)element with tunable luminescence from UV to the visible region owing to the 4 f-related electronic transition,was introduced to construct the first RE-based chiral OIHMHs,R/S-MCC.The chirality is successfully transferred from the chiral organic cations to the inorganic cerium chloride framework in R/S-MCC,as confirmed by the single crystal structures,circular dichroism,and CPL.The emission spectra of R/S-MCC are in the UV region,originating from the characteristic d-f transition of Ce^(3+),which making the Ce-based metal halides are ideal candidates towards CPL light sources in the UV region.Notably,R-and S-MCC are the first RE-based OIHMHs,also the first chiral metalhalides with UV CPL.Our work opens a new avenue for the development of the chiral OIHMH family towards RE-based chiral OIHMH.The RE-based chiral metal halides couple the unique and superior optical,electrical,magnetic,and spintronic properties of RE elements with chirality could accelerate the development of chiral optoelectronics and spintronics toward real applications.
基金supported by the Ministry of Science and Technology of China (National Key R&D Program of China,2022YFB4200400, 2019YFA0705900)the National Natural Science Foundation of China (21935007, 52025033, 22204119),Tianjin City(22JCQNJC00530)Haihe Laboratory of Sustainable Chemical Transformations。
文摘Dimerized small-molecule acceptors(SMAs) built by the conventional connection of terminal groups of monomers have contributed to exciting long-term stabilities of organic solar cells(OSCs). However, device efficiencies, especially fill factors(FFs), still need to be improved. This probably originates from unsymmetrical molecular structure/conformation-determined less compact/ordered molecular stackings, such as ineffective stackings of constraint terminals. Herein, an exotic dimerized SMA of BC-Th is established by bridging the branched groups(BC-type, branch coupling) of two monomers rather than conventional terminal units(TC-type, terminal coupling). Benefiting from the three-dimensional conformation and more uncurbed terminals,BC-Th exhibits multiple molecular orientations along with a larger dielectric constant and electron mobility compared with TCTh. Finally, an efficiency of 17.43% is achieved by BC-Th-based OSCs, along with the highest FF of 79.13% among all dimerized SMAs-based OSCs to date. When introducing L8-BO as the third component, overall enhanced efficiency of 18.05%and FF of 80.11% are further afforded. Contrarily, TC-Th-based OSCs exhibit much inferior PCE of 16.29% and FF of 74.81%,demonstrating the great advantages of “branch coupling” over “terminal coupling” when building dimerized SMAs.
基金supported by the Singapore MOE AcRF Tier 2 Grant (MOE2017-T2-1-073)AME Individual Research Grant (A1983c0026)Agency for Science, Technology, and Research (A*STAR)。
文摘Tailoring the nanostructure and composition of transition metal nitrides is highly important for their use as potent low-cost electrocatalysts. Cobalt nitride(CoN) exhibits strong catalytic activity for oxygen evolution reaction(OER). However, its poor catalytic efficiency for oxygen reduction reaction(ORR) hinders its application in rechargeable zinc-air batteries(ZABs) as the air cathode. In this work, we deploy the effective strategy of Mn doping to improve both OER and ORR activity of CoN nanowires as the cathode material for ZAB. Theoretical calculation predicts that moderate Mn doping in cobalt nitride results in a downshift of the d-band center and reduces the adsorption energy of reaction intermediates. With ~10 at% Mn dopants, stronger catalysis activities for both OER and ORR are achieved compared to pure CoN nanowires. Subsequently, both aqueous and flexible quasi-solid-state ZABs are constructed using the Mn-doped CoN nanowires array as additive-free air cathode. Both types of devices present large open circuit potential, high power density and long-cycle stability. This work pushes forward the progress in developing cost-effective ZABs.
基金supported by the National Natural Science Foundation of China(22005152,22275101).
文摘Lead-free halide perovskite materials possess low toxicity,broadband luminescence and robust stability compared with conventional lead-based perovskites,thus holding great promise for eyes-friendly white light LEDs.However,the traditionally used preparation methods with a long period and limited product yield have curtailed the commercialization of these materials.Here we introduce a universal hydrochloric acid-assistant powder-to-powder strategy which can accomplish the goals of thermal-,pressure-free,eco-friendliness,short time,low cost and high product yield,simultaneously.The obtained Cs_(2)Na_(0.9)Ag_(0.1)In_(0.95)Bi_(0.05)Cl_(6)microcrystals exhibit bright self-trapped excitons emission with quantum yield of(98.3±3.8)%,which could retain(90.5±1.3)%and(96.8±0.8)%after continuous heating or ultraviolet-irradiation for 1000 h,respectively.The phosphor converted-LED exhibited near-unity conversion efficiency from ultraviolet chip to self-trapped excitons emission at~200 mA.Various ions doping(such as Cs_(2)Na_(0.9)Ag_(0.1)InCl_(6):Ln^(3+))and other derived lead-free perovskite materials(such as Cs_(2)ZrCl_(6)and Cs_(4)MnBi_(2)Cl_(12))with high luminous performance are all realized by our proposed strategy,which has shown excellent availability towards commercialization.
基金supported by the Ministry of Science and Technology of the People’s Republic of China(Mo ST,2022YFB4200400,2019YFA0705900)the National Natural Science Foundation of China(21935007,52025033,51873089)+3 种基金Tianjin city(20JCZDJC00740,22JCQNJC00530)111 Project(B12015)the Fundamental Research Funds for the Central Universities,Nankai University(023-ZB22000105,020-ZB22000110,020-92220002)Haihe Laboratory of Sustainable Chemical Transformations。
文摘All-small organic solar cells(ASM OSCs)inherit the advantages of the distinct merits of small molecules,such as well-defined structures and less batch-to-batch variation.In comparison with the rapid development of polymer-based OSCs,more efforts are needed to devote to improving the performance of ASM OSCs to close the performance gap between ASM and polymer-based OSCs.Herein,a well-known p-dopant named fluoro-7,7,8,8-tetracyano-p-quinodimethane(FTCNQ)was introduced to a highefficiency system of HD-1:BTP-e C9,and a high power conversion efficiency(PCE)of 17.15%was achieved due to the improved electrical properties as well as better morphology of the active layer,supported by the observed higher fill factor(FF)of 79.45%and suppressed non-radiative recombination loss.Furthermore,combining with the further morphology optimization from solvent additive of 1-iodonaphthalene(IN)in the blend film,the HD-1:BTP-e C9-based device with the synergistic effects of both FTCNQ and IN demonstrates a remarkable PCE of 17.73%(certified as 17.49%),representing the best result of binary ASM OSCs to date.
基金supported by the National Natural Sciences Foundation of China (21935007, 52025033, 51873089)MoST of China (2019YFA0705900)+2 种基金Tianjin city (20JCZDJC00740)111 Project (B12015)the Opening Project of State Key Laboratory of Luminescent Materials and Devices (SCUT, 2021-skllmd-09)。
文摘The central unit(benzo[c][1,2,5]thiadiazole) in Y6 series of molecules plays a determining role in their unique intermolecular packing for a three-dimensionally(3D) network, largely endowing their organic solar cells(OSCs) with so far the best power conversion efficiencies(PCEs) and also largely suppressed energy losses(Eloss). Despite its vital role in molecular packing, very few explorations for central unit have been conducted due to possibly the constructing challenge of central heterocyclic units.Herein, a highly efficient acceptor-donor-acceptor(A-D-A) type electron acceptor, CH17, has been designed and constructed,featured with a prominent π extension in both directions of the central and end units with respect to Y6 series. Such a multiple and much enhanced conjugation extension in CH17 enables a much more effective and compact 3D molecular packing compared with that of Y6 supported by X-ray single crystal and other analysis, mainly caused by a newly observed distinctive dual “end unit to central unit” packing mode. This much favorable molecular packing, also kept in its blends with donor materials, leads a larger electron and hole transfer integrals and hence much improved charge transport, and reduced energetic disorders in CH17blends. More importantly, the observed upshifted charge transfer(CT) state of CH17 blends compared with that of Y6, due to its increased molecular conjugation extension in both directions, further enhances the hybridization between its CT and local exciton(LE) states, resulting in higher luminescence efficiency, much suppressed non-radiative recombination loss and smaller Elosswith respect to that of Y6. Consequently, an excellent PCE of 17.84% is achieved with PM6 as the donor in a binary device compared with a PCE of 16.27% for the controlled Y6 device. Furthermore, a further improved PCE of 18.13% is achieved by CH17-based ternary single-junction OSCs along with a markedly reduced Elossof 0.49 e V and larger open-circuit voltage(Voc) of0.89 V, compared with that(16.27% of PCE, 0.85 V of Voc, and 0.53 e V of Eloss) of the control device using Y6. This significantly improved photovoltaic performance caused by molecular multiple conjugation extension, especially through the largely unexplored central unit, indicates that there is still much room to further enhance OSC performance by addressing the most important issue for OSC, i.e, the smaller Voccaused by larger Eloss, through engineering molecular packing by designing/tuning molecule more dedicatedly.
基金supported by the National Basic Research Program of China(2012CB933401)the National Natural Science Foundation of China(51472124+3 种基金5127309321374050)the Natural Science Foundation of Tianjin(13RCGFGX01121)Science Research Project of Langfang Teachers University(LSLB201401)
文摘The possible practical limits for the specific surface area and capacitance performance of bulk sp^2 carbon materials were investigated experimentally and theoretically using a variety of carbon materials. We find the limit for the specific surface area to be 3500–3700 m^2 g^(-1), and based on this, the corresponding best capacitance was predicted for various electrolyte systems. A model using an effective ionic diameter for the electrolyte ions was proposed and used to calculate the theoretical capacitance. A linear dependence of experimental capacitance versus effective specific surface area of various sp^2 carbon materials was obtained for all studied ionic liquid, organic and aqueous electrolyte systems. Furthermore, excellent agreement between the theoretical and experimental capacitance was observed for all the tested sp^2 carbon materials in these electrolyte systems, indicating that this model can be applied widely in the evaluation of various carbon materials for supercapacitors.