We numerically investigate the injection process of electrons from metal electrodes to one-dimensional organic molecules by combining the extended Su Schrieffer Heeger (SSH) model with a nonadiabatic dynamics method...We numerically investigate the injection process of electrons from metal electrodes to one-dimensional organic molecules by combining the extended Su Schrieffer Heeger (SSH) model with a nonadiabatic dynamics method. It is found that a match between the Fermi level of electrodes and the highest occupied molecular orbital (HOMO) or the lowest unoccupied molecular orbital (LUMO) of organic molecules can be greatly affected by the length of the organic chains, which has a great impact on electron injection. The correlation between oligomers and electrodes is found to open more efficient channels for electron injection as compared with that in polymer/electrode structures. For oligomer/electrode structures, we show that the Schottky barrier essentially does not affect the electron injection as the electrode work function is smaller than a critical value work-function electrode. For polymer/electrode structures This means that the Schottky barrier is pinned for a small we find that it is possible for the Fermi level of electrodes to be pinned to the polaronic level. The condition under which the Fermi level of electrodes exceeds the polaronic level of polymers is shown to not always lead to spontneous electron transfer from electrodes to polymers.展开更多
Replacing traditional polymer-based precursors with small molecules is a promising pathway toward facile and controllable preparation of porous carbons but remains a prohibitive challenge because of the high volatilit...Replacing traditional polymer-based precursors with small molecules is a promising pathway toward facile and controllable preparation of porous carbons but remains a prohibitive challenge because of the high volatility of small molecules.Herein,a simple,general,and controllable method is reported to prepare porous carbons by converting small organic molecules into organic molecular salts followed by pyrolysis.The robust electrostatic force holding organic molecular salts together leads to negligible volatility and thus ensures the formation of carbons under high-temperature pyrolysis.Meanwhile,metal moieties in organic molecular salts can be evolved into in-situ templates or activators during pyrolysis to create nanopores.The modular nature of organic molecular salts allows easy control of the porosity and chemical doping of carbons at a molecular level.The sulfur-doped carbon prepared by the ionic solid strategy can serve as robust support to prepare small-sized intermetallic PtCo catalysts,which exhibit a high mass activity of 1.62 A·mgPt^(−1)in catalyzing oxygen reduction reaction for fuel cell applications.展开更多
Aqueous organic redox flow batteries(RFBs)exhibit favorable characteristics,such as tunability,multielectron transfer capability,and stability of the redox active molecules utilized as anolytes and catholytes,making t...Aqueous organic redox flow batteries(RFBs)exhibit favorable characteristics,such as tunability,multielectron transfer capability,and stability of the redox active molecules utilized as anolytes and catholytes,making them very viable contenders for large-scale grid storage applications.Considerable attention has been paid on the development of efficient redox-active molecules and their performance optimization through chemical substitutions at various places on the backbone as part of the pursuit for high-performance RFBs.Despite the fact that electrodes are vital to optimal performance,they have not garnered significant attention.Limited research has been conducted on the effects of electrode modifications to improve the performance of RFBs.The primary emphasis has been given on the impact of electrode engineering to augment the efficiency of aqueous organic RFBs.An overview of electron transfer at the electrode-electrolyte interface is provided.The implications of electrode modification on the performance of redox flow batteries,with a particular focus on the anodic and cathodic half-cells separately,are then discussed.In each section,significant discrepancies surrounding the effects of electrode engineering are thoroughly examined and discussed.Finally,we have presented a comprehensive assessment along with our perspectives on the future trajectory.展开更多
In contrast to the widely reported excited-state single proton-transfer,excited-state multiple proton transfer(ESMPT)containing two or more intra-or inter-molecular proton transfers has greatly expanded the research s...In contrast to the widely reported excited-state single proton-transfer,excited-state multiple proton transfer(ESMPT)containing two or more intra-or inter-molecular proton transfers has greatly expanded the research scope of the excited-state proton transfers.In recent decades,ESMPT-active organic molecules have attracted much attention owing to their unique photophysical properties,such as large magnitude Stokes shifts and dual emission.These photophysical properties facilitate the application of the organic molecules in organic solid-state lasers,fluorescent probes and sensors,and molecular switches.Herein,we introduce the fundamentals of the ESMPT and review the recent advances in different types of ESMPTs in organic molecules.Finally,we present our conclusions and the future development prospects of the ESMPT in organic molecules.展开更多
Nature has provided us the assurance and inspiration for thousands of years in synthesizing value-added chemicals,with the assistance of reactive hydrogen species,and water as the ultimate hydrogen source.However,the ...Nature has provided us the assurance and inspiration for thousands of years in synthesizing value-added chemicals,with the assistance of reactive hydrogen species,and water as the ultimate hydrogen source.However,the natural photosynthesis is inefficient due to some intrinsic properties,urging people not only to learn from but also surpass during nature imitation.In this review,we summarized recent progresses on reactive hydrogen species-assisted nanocatalytic reduction of organic molecules towards value-added fine chemicals and pharmaceuticals,with water as the hydrogen source,and especially highlighted how photocatalytically or electrocatalytically evolved reactive hydrogen species synergize with biocatalytic centers and nanocatalytic sites for reduction of organic molecules.The design principles of collaborative semi-artificial systems and nanocatalytic artificial systems,the structure tuning of catalysts for the evolution and utilization of hydrogen species,and the determination of reactive hydrogen species for mechanistic insights were discussed in detail.Finally,perspectives were provided for further advancing this emerging area of nanocatalytic reduction of organic molecules from water(or proton)and organics.展开更多
We have synthesized two photovoltaic molecules(HEX-3TVT-ID and EH-3TVT-ID) based on vinylenebridged oligothiophene applied as donor for the solution-processable bulk-heterojunction organic solar cells(OSCs). Vinyl...We have synthesized two photovoltaic molecules(HEX-3TVT-ID and EH-3TVT-ID) based on vinylenebridged oligothiophene applied as donor for the solution-processable bulk-heterojunction organic solar cells(OSCs). Vinylene unit was introduced as π-bridge in the oligothiophenes with 1,3-indenedione as end group and 4,4’-dihexyl-2,2’:5’,2’-terthiophene or 3’,4’-di(octan-3-yl)-2,2’:5’,2’-terthiophene as core,respectively. Due to the different substituent positions of the alkyl group relative to the vinylene unit in the terthiophene, HEX-3TVT-ID and EH-3TVT-ID show different optical and electrochemical properties, corresponding to the photovoltaic performance of the OSCs devices. The power conversion efficiency(PCE) of the OSCs based on a blend of HEX-3TVT-ID and PC71BM(1:0.8, weight ratio, 0.5% CN) reached 2.3%. In comparison, the OSCs based on the blend of EH-3TVT-ID and PC71BM in the weight ratio of 1:1 without the additive show a higher PCE of 2.7%, with a typically high VOC of 0.93 V, under the illumination of AM 1.5, 100 mW cm-2.展开更多
BrCF_2SO_2Br, prepared from sulfinatodehalogenation of CF_2Br_2 followed by bromination of the intermediate BrCF_2SO_2Na, was shown to be a mild and efficient bromodifluoromethylating agent.
With the support by the Major Program of the National Natural Science Foundation of China,a research group led by Prof.Shen Zhiqiang(沈志强)from Shanghai Astronomical Observatory,Chinese Academy of Sciences reports ...With the support by the Major Program of the National Natural Science Foundation of China,a research group led by Prof.Shen Zhiqiang(沈志强)from Shanghai Astronomical Observatory,Chinese Academy of Sciences reports the detection of widespread CH2OHCHO(glycolaldehyde) and展开更多
An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipo...An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipole layer at the internal Helmholtz electrical double layers(HEDLs) under the preferential adsorption function of formate on Zn surface,reducing the occurrence of side reactions at phase interface.Meanwhile,free formate in HEDLs regulates the Zn^(2+) solvation sheath structure to accelerate the desolvation,transference,and deposition kinetics of Zn^(2+).Besides,the hydrolysis reaction of zinc formate increases the hydrogen evolution overpotential,inhibiting the thermodynamic tendency of hydrogen evolution.Consequently,it presents stable cycle for more than 2400 h at 5 mA cm^(-2),as well as an average Coulombic efficiency of 99.8% at 1 A g^(-1) after 800 cycles in the Zn‖VO_(2) full cell.The interphase engineering strategy zinc anode by organic small molecular brings new possibility towards high-performance aqueous zinc-ion batteries.展开更多
For flow batteries(FBs), the current technologies are still expensive and have relatively low energy density, which limits their large-scale applications. Organic FBs(OFBs) which employ organic molecules as redox-acti...For flow batteries(FBs), the current technologies are still expensive and have relatively low energy density, which limits their large-scale applications. Organic FBs(OFBs) which employ organic molecules as redox-active materials have been considered as one of the promising technologies for achieving lowcost and high-performance. Herein, we present a critical overview of the progress on the OFBs, including the design principles of key components(redox-active molecules, membranes, and electrodes) and the latest achievement in both aqueous and nonaqueous systems. Finally, future directions in explorations of the high-performance OFB for electrochemical energy storage are also highlighted.展开更多
Small molecule organic photovoltaics(SMPVs) were prepared by utilizing liquid crystalline donor material BTR-Cl and two similar optical bandgap non-fullerene acceptor materials BTP-BO-4 F and Y6.The BTPBO-4 F and Y6 h...Small molecule organic photovoltaics(SMPVs) were prepared by utilizing liquid crystalline donor material BTR-Cl and two similar optical bandgap non-fullerene acceptor materials BTP-BO-4 F and Y6.The BTPBO-4 F and Y6 have the similar optical bandgap and different absorption coefficients.The corresponding binary SMPVs exhibit different short circuit current density(/sc)(20.38 vs.23.24 mA cm^(-2)),and fill factor(FF)(70.77% vs.67.21%).A 14.46% power conversion efficiency(PCE) is acquired in ternary SMPVs with 30 wt% Y6,companied with a JSC of 24.17 mA cm^(-2) a FF of 68.78% and an open circuit voltage(Voc) of 0.87 V.The improvement on PCE of ternary SMPVs should originate from the well trade-off between phase separation and photon harvesting of ternary active layers by incorporating 30 wt% Y6 in acceptors.This work may deliver insight onto the improved performance of SMPVs by superposing the superiorities of binary SMPVs with similar optical bandgap acceptors into one ternary cell.展开更多
Aggregation effect caused by the intermolecular hydrogen-bonding interactions on two-photon absorption prop- erties of (E)-4-(2-nitrovinyl) benzenamine molecules is studied at a hybrid density functional level. Th...Aggregation effect caused by the intermolecular hydrogen-bonding interactions on two-photon absorption prop- erties of (E)-4-(2-nitrovinyl) benzenamine molecules is studied at a hybrid density functional level. The geometry optimization studies indicate that there exist two probable conformations for the dimers and three for the trimers. A strong red-shift of the charge-transfer states is shown. The two-photon absorption cross sections of the molecule for certain conformations are greatly enhanced by the aggregation effect, from which a ratio of 1.0:2.6:3.6 is found for the molecule and its dimer and trimer with nearly planar structures. Namely, a 30 or 20 percent increase of the two-photon absorption cross section is observed.展开更多
Deposition patterns of tetracyanoquinodimethane (TCNQ) molecules on different surfaces are investigated by atomic force microscopy. A homemade physical vapour deposition system allows the better control of molecule ...Deposition patterns of tetracyanoquinodimethane (TCNQ) molecules on different surfaces are investigated by atomic force microscopy. A homemade physical vapour deposition system allows the better control of molecule deposition. Taking advantage of this system, we investigate TCNQ thin film growth on both SiO2 and mica surfaces. It is found that dense island patterns form at a high deposition rate, and a unique seahorse-like pattern forms at a low deposition rate. Growth patterns on different substrates suggest that the fractal pattern formation is dominated by molecule-molecule interaction. Finally, a phenomenal "two-branch" model is proposed to simulate the growth process of the seahorse pattern.展开更多
Low dimensional perovskites have recently attracted much attention due to their vertical growth of crys- talline orientation, excellent film morphology, and long-term humidity, light, and heat stability, How- ever, lo...Low dimensional perovskites have recently attracted much attention due to their vertical growth of crys- talline orientation, excellent film morphology, and long-term humidity, light, and heat stability, How- ever, low dimensional perovskites suffer fl'om low power conversion efficiency (PCE) with respect to their three dimensional analogues. Therefore, it is imperative to find excellent low-dimensional perovskite materials for improving the PCE. Previous work has demonstrated that bulkier organic molecules, e,g., C6Hs(CH2)2NH3+ (PEA+), CH3(CH2)3NH3+(n-BAT, iso-BA+), C2H4NH3 +, and polyethylenimine cations (PEI+), play an important role in the formation of low-dimensional perovskites. In this review, we review the recent development of low dimensional perovskites for solar cells application in terms of film preparation, photophysics, and stability of perovskites, as well as the related device structure and physics. We have also discussed the future development of low-dimensional perovskites from materials design, fabri- cation processes, and device structure.展开更多
Although the adverse impacts of ocean acidification(OA)on marine calcifiers have been investigated extensively,the anti-stress capabilities regulated by increased light availability are unclear.Herein,the interactive ...Although the adverse impacts of ocean acidification(OA)on marine calcifiers have been investigated extensively,the anti-stress capabilities regulated by increased light availability are unclear.Herein,the interactive effects of three light levels(30μmol photons/(m^(2)·s),150μmol photons/(m^(2)·s),and 240μmol photons/(m^(2)·s)combined with two pCO_(2)concentrations(400 ppmv and 1400 ppmv)on the physiological acclimation of the calcifying macroalga Halimeda opuntia were investigated using a pCO_(2)-light coupling experiment.The OA negatively influenced algal growth,calcification,photosynthesis,and other physiological performances in H.opuntia.The relative growth rate under elevated pCO_(2)conditions significantly declined by 13.14%−41.29%,whereas net calcification rates decreased by nearly three-fold under OA conditions.Notably,increased light availability enhanced stress resistance through the accumulation of soluble organic molecules,especially soluble carbohydrate,soluble protein,and free amino acids,and in combination with metabolic enzyme-driven activities,OA stress was alleviated.The carotenoid content under low light conditions increased markedly,and the rapid light curve of the relative electron transport rate was enhanced significantly by increasing light intensities,indicating that this new organization of the photosynthetic machinery in H.opuntia accommodated light variations and elevated pCO_(2)conditions.Thus,the enhanced metabolic performance of the calcifying macroalga H.opuntia mitigated OA-related stress.展开更多
Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single-junction solar cells. Employing the wide bandgap perovskite materia...Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single-junction solar cells. Employing the wide bandgap perovskite materials and low bandgap organic materials as absorber layers for front and rear subcells, respectively, to construct perovskite/organic TSCs can complementarily absorb sunlight in ultraviolet-visible (UV-Vis) range by front perovskite and near-infrared (NIR) range by rear organic molecules, thus reducing the thermalization energy losses. Besides the subcells, the interconnection layer (ICL), which physically and electrically connects the front and rear subcells, is also an important tunnel junction to recombine charges. In this review, we summarize the optimization strategies of wide bandgap perovskites for front subcell, narrow bandgap organic material for rear subcell, and the ICLs employed in monolithic perovskite/organic TSCs.展开更多
This paper investigates the dynamics of cooperative emissions in a cascade three-level system driven by an ultra, short laser pulse by solving numerically the full-wave Maxwell-Bloch equations. The 4, 4'-bis(dimethy...This paper investigates the dynamics of cooperative emissions in a cascade three-level system driven by an ultra, short laser pulse by solving numerically the full-wave Maxwell-Bloch equations. The 4, 4'-bis(dimethylamino) stilbene molecule is used as the model molecule because of its strong two-photon absorption property. The two-colour cooperative emissions are studied as functions of molecular number density and dephasing rate of the dipole coherence. The propagation effects on the evolution of the cooperative radiations are also taken into account. The cooperative radiations are enhanced for large number density of the molecule, while the fast dephasing of the dipole coherence reduces the intensity of the cooperative radiations and delays the emission times or even inhibits the formation of the emissions. The delay time of the radiation decreases with the increase of the molecular number density and the propagation distance.展开更多
The influence of rotational isomerism on the two-photon absorption (TPA) of FTC chromophores has been investi- gated using the quadratic response theory with the B3LYP functional. Eight rotamers induced by three rot...The influence of rotational isomerism on the two-photon absorption (TPA) of FTC chromophores has been investi- gated using the quadratic response theory with the B3LYP functional. Eight rotamers induced by three rotatable single bonds in the molecule are fully optimized, and it is found that their conformational energies are nearly degenerate. Our calculations demonstrate that rotational isomerism has an important effect on the TPA cross sections. For a certain rotamer, the maximum TPA cross section is enhanced significantly. In addition, in the longer wavelength region, the rotational isomerism could lead to a large shift of the TPA position.展开更多
Aiming to reduce the defects of perovskite film and improve carrier transport,an organic small molecule,benzo[d]isothiazol-3(2H)-one 1,1-dioxide(OBS),is introduced as an additive in the solution-processing of perovski...Aiming to reduce the defects of perovskite film and improve carrier transport,an organic small molecule,benzo[d]isothiazol-3(2H)-one 1,1-dioxide(OBS),is introduced as an additive in the solution-processing of perovskite and prepare uniform perovskite films with a continuous distribution of OBS at grain boundaries.Fourier trans-form infrared spectroscopy and X-ray photoelectron spectroscopy are conducted to reveal the interactions of hydrogen bonding and coordina tion bonding between OBS and perovskite.Various characterizations(including X-ray diffraction,UV-vis spectroscopy,electrochemical impedance spectroscopy,etc.)are conducted to uncover the effect of OBS on device performance.Consequently,high efficiency of 23.26%is obtained for the OBS-treated device,while the control device shows only a companion efficiency of 21.60%.展开更多
During the mass formation of aggregates of molecules in a gelatin film dyed with the mixture of chrysophenine and acridine yellow dyes, photo-reorientation, photo-disorientation, and photo-orientation of the molecules...During the mass formation of aggregates of molecules in a gelatin film dyed with the mixture of chrysophenine and acridine yellow dyes, photo-reorientation, photo-disorientation, and photo-orientation of the molecules are observed. Based on these observations, the photo-induction of granular aniso tropy may be realized.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 20974101 and 21174135)
文摘We numerically investigate the injection process of electrons from metal electrodes to one-dimensional organic molecules by combining the extended Su Schrieffer Heeger (SSH) model with a nonadiabatic dynamics method. It is found that a match between the Fermi level of electrodes and the highest occupied molecular orbital (HOMO) or the lowest unoccupied molecular orbital (LUMO) of organic molecules can be greatly affected by the length of the organic chains, which has a great impact on electron injection. The correlation between oligomers and electrodes is found to open more efficient channels for electron injection as compared with that in polymer/electrode structures. For oligomer/electrode structures, we show that the Schottky barrier essentially does not affect the electron injection as the electrode work function is smaller than a critical value work-function electrode. For polymer/electrode structures This means that the Schottky barrier is pinned for a small we find that it is possible for the Fermi level of electrodes to be pinned to the polaronic level. The condition under which the Fermi level of electrodes exceeds the polaronic level of polymers is shown to not always lead to spontneous electron transfer from electrodes to polymers.
基金We acknowledge the funding support from the National Key Research and Development Program of China(No.2018YFA0702001)the National Natural Science Foundation of China(No.22071225)+6 种基金the Fundamental Research Funds for the Central Universities(No.WK2060190103)the Joint Funds from Hefei National Synchrotron Radiation Laboratory(No.KY2060000175)the Natural Science Foundation of Guangdong Province(No.2021A1515012356)the Research Grant for Scientific Platform and Project of Guangdong Provincial Education office(No.2019KTSCX151)Shenzhen Government’s Plan of Science and Technology(No.JCYJ20180305125247308)the Collaborative Innovation Program of Hefei Science Center of CAS(No.2021HSC-CIP015)L.D.F.acknowledges the support from the Instrumental Analysis Center of Shenzhen University(Xili Campus).
文摘Replacing traditional polymer-based precursors with small molecules is a promising pathway toward facile and controllable preparation of porous carbons but remains a prohibitive challenge because of the high volatility of small molecules.Herein,a simple,general,and controllable method is reported to prepare porous carbons by converting small organic molecules into organic molecular salts followed by pyrolysis.The robust electrostatic force holding organic molecular salts together leads to negligible volatility and thus ensures the formation of carbons under high-temperature pyrolysis.Meanwhile,metal moieties in organic molecular salts can be evolved into in-situ templates or activators during pyrolysis to create nanopores.The modular nature of organic molecular salts allows easy control of the porosity and chemical doping of carbons at a molecular level.The sulfur-doped carbon prepared by the ionic solid strategy can serve as robust support to prepare small-sized intermetallic PtCo catalysts,which exhibit a high mass activity of 1.62 A·mgPt^(−1)in catalyzing oxygen reduction reaction for fuel cell applications.
基金the financial support received from Interdisciplinary Research Center for Hydrogen Technologies and Carbon Management(IRC-HTCM)at King Fahd University of Petroleum and Minerals(KFUPM),specifically under project#INHE2213。
文摘Aqueous organic redox flow batteries(RFBs)exhibit favorable characteristics,such as tunability,multielectron transfer capability,and stability of the redox active molecules utilized as anolytes and catholytes,making them very viable contenders for large-scale grid storage applications.Considerable attention has been paid on the development of efficient redox-active molecules and their performance optimization through chemical substitutions at various places on the backbone as part of the pursuit for high-performance RFBs.Despite the fact that electrodes are vital to optimal performance,they have not garnered significant attention.Limited research has been conducted on the effects of electrode modifications to improve the performance of RFBs.The primary emphasis has been given on the impact of electrode engineering to augment the efficiency of aqueous organic RFBs.An overview of electron transfer at the electrode-electrolyte interface is provided.The implications of electrode modification on the performance of redox flow batteries,with a particular focus on the anodic and cathodic half-cells separately,are then discussed.In each section,significant discrepancies surrounding the effects of electrode engineering are thoroughly examined and discussed.Finally,we have presented a comprehensive assessment along with our perspectives on the future trajectory.
基金financially supported by the National Natural Science Foundation of China (52173177,21971185,22105139)China Postdoctoral Science Foundation (2020M681707)+1 种基金funded by the Collaborative Innovation Center of Suzhou Nano Science and Technology (CIC-Nano)by the “111” Project of the State Administration of Foreign Experts Affairs of China
文摘In contrast to the widely reported excited-state single proton-transfer,excited-state multiple proton transfer(ESMPT)containing two or more intra-or inter-molecular proton transfers has greatly expanded the research scope of the excited-state proton transfers.In recent decades,ESMPT-active organic molecules have attracted much attention owing to their unique photophysical properties,such as large magnitude Stokes shifts and dual emission.These photophysical properties facilitate the application of the organic molecules in organic solid-state lasers,fluorescent probes and sensors,and molecular switches.Herein,we introduce the fundamentals of the ESMPT and review the recent advances in different types of ESMPTs in organic molecules.Finally,we present our conclusions and the future development prospects of the ESMPT in organic molecules.
基金the financial support of the National Natural Science Foundation of China(Nos.22102102,21805191 and 21972094)China Postdoctoral Science Foundation(No.2021T140472)+4 种基金Guangdong Basic and Applied Basic Research Foundation(No.2020A1515010982)Educational Commission of Guangdong Province(No.839-0000013131)Shenzhen Stable Support Project(Nos.20200812160737002 and 20200812122947002)Shenzhen Peacock Plan(Nos.KQTD2016053112042971,20210308299C,20180921273B,20210802524B,and 827-000421)Shenzhen Science and Technology Program(Nos.JCYJ20190808142001745 and RCJC20200714114434086)。
文摘Nature has provided us the assurance and inspiration for thousands of years in synthesizing value-added chemicals,with the assistance of reactive hydrogen species,and water as the ultimate hydrogen source.However,the natural photosynthesis is inefficient due to some intrinsic properties,urging people not only to learn from but also surpass during nature imitation.In this review,we summarized recent progresses on reactive hydrogen species-assisted nanocatalytic reduction of organic molecules towards value-added fine chemicals and pharmaceuticals,with water as the hydrogen source,and especially highlighted how photocatalytically or electrocatalytically evolved reactive hydrogen species synergize with biocatalytic centers and nanocatalytic sites for reduction of organic molecules.The design principles of collaborative semi-artificial systems and nanocatalytic artificial systems,the structure tuning of catalysts for the evolution and utilization of hydrogen species,and the determination of reactive hydrogen species for mechanistic insights were discussed in detail.Finally,perspectives were provided for further advancing this emerging area of nanocatalytic reduction of organic molecules from water(or proton)and organics.
基金supported by the National Natural Science Foundation of China (51272033, 51572037, 51603021)333 Project of Jiangsu Province (BRA2017353)the Priority Academic Program Development of Jiangsu Higher Education Institutions and Anhui Provincial Natural Science Foundation (1608085QF156)
文摘We have synthesized two photovoltaic molecules(HEX-3TVT-ID and EH-3TVT-ID) based on vinylenebridged oligothiophene applied as donor for the solution-processable bulk-heterojunction organic solar cells(OSCs). Vinylene unit was introduced as π-bridge in the oligothiophenes with 1,3-indenedione as end group and 4,4’-dihexyl-2,2’:5’,2’-terthiophene or 3’,4’-di(octan-3-yl)-2,2’:5’,2’-terthiophene as core,respectively. Due to the different substituent positions of the alkyl group relative to the vinylene unit in the terthiophene, HEX-3TVT-ID and EH-3TVT-ID show different optical and electrochemical properties, corresponding to the photovoltaic performance of the OSCs devices. The power conversion efficiency(PCE) of the OSCs based on a blend of HEX-3TVT-ID and PC71BM(1:0.8, weight ratio, 0.5% CN) reached 2.3%. In comparison, the OSCs based on the blend of EH-3TVT-ID and PC71BM in the weight ratio of 1:1 without the additive show a higher PCE of 2.7%, with a typically high VOC of 0.93 V, under the illumination of AM 1.5, 100 mW cm-2.
文摘BrCF_2SO_2Br, prepared from sulfinatodehalogenation of CF_2Br_2 followed by bromination of the intermediate BrCF_2SO_2Na, was shown to be a mild and efficient bromodifluoromethylating agent.
文摘With the support by the Major Program of the National Natural Science Foundation of China,a research group led by Prof.Shen Zhiqiang(沈志强)from Shanghai Astronomical Observatory,Chinese Academy of Sciences reports the detection of widespread CH2OHCHO(glycolaldehyde) and
基金supported by the National Natural Science Foundation of China (Grant Nos. 52072322, 51604250)the Sichuan Science and Technology Program, China (Grant Nos. 2022YFG0294, 2019-GH02-00052-HZ)the Undergraduate Innovation and Entrepreneurship Program (S202210615189)。
文摘An organic small molecule additive zinc formate is introduced to construct stable Zn metal interphase by electrochemical kinetic control and thermodynamic adjustment.It partially forms a water-formate concomitant dipole layer at the internal Helmholtz electrical double layers(HEDLs) under the preferential adsorption function of formate on Zn surface,reducing the occurrence of side reactions at phase interface.Meanwhile,free formate in HEDLs regulates the Zn^(2+) solvation sheath structure to accelerate the desolvation,transference,and deposition kinetics of Zn^(2+).Besides,the hydrolysis reaction of zinc formate increases the hydrogen evolution overpotential,inhibiting the thermodynamic tendency of hydrogen evolution.Consequently,it presents stable cycle for more than 2400 h at 5 mA cm^(-2),as well as an average Coulombic efficiency of 99.8% at 1 A g^(-1) after 800 cycles in the Zn‖VO_(2) full cell.The interphase engineering strategy zinc anode by organic small molecular brings new possibility towards high-performance aqueous zinc-ion batteries.
基金supported by the China Natural Science Foundation(U1808209)the CAS-DOE program,CAS(QYZDB-SSWJSC032)+1 种基金the Key R&D project of Dalian(2018YF17GX020)the DICP funding(ZZBS201707)。
文摘For flow batteries(FBs), the current technologies are still expensive and have relatively low energy density, which limits their large-scale applications. Organic FBs(OFBs) which employ organic molecules as redox-active materials have been considered as one of the promising technologies for achieving lowcost and high-performance. Herein, we present a critical overview of the progress on the OFBs, including the design principles of key components(redox-active molecules, membranes, and electrodes) and the latest achievement in both aqueous and nonaqueous systems. Finally, future directions in explorations of the high-performance OFB for electrochemical energy storage are also highlighted.
基金the financial supporting from the NSFC(61975006,61675017)NSFRPSI(Y72Z090Q10)+3 种基金the NSFCQ(cstc2019jcyj-msxm X0400)the NYTPP(R52A199Z11)the YIPACAS(E0296104)the BNSF(4192049)。
文摘Small molecule organic photovoltaics(SMPVs) were prepared by utilizing liquid crystalline donor material BTR-Cl and two similar optical bandgap non-fullerene acceptor materials BTP-BO-4 F and Y6.The BTPBO-4 F and Y6 have the similar optical bandgap and different absorption coefficients.The corresponding binary SMPVs exhibit different short circuit current density(/sc)(20.38 vs.23.24 mA cm^(-2)),and fill factor(FF)(70.77% vs.67.21%).A 14.46% power conversion efficiency(PCE) is acquired in ternary SMPVs with 30 wt% Y6,companied with a JSC of 24.17 mA cm^(-2) a FF of 68.78% and an open circuit voltage(Voc) of 0.87 V.The improvement on PCE of ternary SMPVs should originate from the well trade-off between phase separation and photon harvesting of ternary active layers by incorporating 30 wt% Y6 in acceptors.This work may deliver insight onto the improved performance of SMPVs by superposing the superiorities of binary SMPVs with similar optical bandgap acceptors into one ternary cell.
基金Project supported by the National Basic Research Program of China (Grant No. 2006CB806000)the Open Fund of the State Key Laboratory of High Field Laser Physics (Shanghai Institute of Optics and Fine Mechanics)the National Natural Science Foundation of China (Grant No. 10974121)
文摘Aggregation effect caused by the intermolecular hydrogen-bonding interactions on two-photon absorption prop- erties of (E)-4-(2-nitrovinyl) benzenamine molecules is studied at a hybrid density functional level. The geometry optimization studies indicate that there exist two probable conformations for the dimers and three for the trimers. A strong red-shift of the charge-transfer states is shown. The two-photon absorption cross sections of the molecule for certain conformations are greatly enhanced by the aggregation effect, from which a ratio of 1.0:2.6:3.6 is found for the molecule and its dimer and trimer with nearly planar structures. Namely, a 30 or 20 percent increase of the two-photon absorption cross section is observed.
基金Project supported by the National Natural Science Foundation of China(Grant No.10774176)the National Basic Research Program of China(Grant No.2006CB806202)
文摘Deposition patterns of tetracyanoquinodimethane (TCNQ) molecules on different surfaces are investigated by atomic force microscopy. A homemade physical vapour deposition system allows the better control of molecule deposition. Taking advantage of this system, we investigate TCNQ thin film growth on both SiO2 and mica surfaces. It is found that dense island patterns form at a high deposition rate, and a unique seahorse-like pattern forms at a low deposition rate. Growth patterns on different substrates suggest that the fractal pattern formation is dominated by molecule-molecule interaction. Finally, a phenomenal "two-branch" model is proposed to simulate the growth process of the seahorse pattern.
基金financially supported by the National Basic Research Program of China,Fundamental Studies of Perovskite Solar Cells(Grant 2015CB932200)the Natural Science Foundation of China(Grant 51035063)+2 种基金Natural Science Foundation of Jiangsu Province,China(Grants 55135039 and 55135040)Jiangsu Specially-Appointed Professor program(Grant 54907024)Startup from Nanjing Tech University(Grants 3983500160,3983500151,and 44235022)
文摘Low dimensional perovskites have recently attracted much attention due to their vertical growth of crys- talline orientation, excellent film morphology, and long-term humidity, light, and heat stability, How- ever, low dimensional perovskites suffer fl'om low power conversion efficiency (PCE) with respect to their three dimensional analogues. Therefore, it is imperative to find excellent low-dimensional perovskite materials for improving the PCE. Previous work has demonstrated that bulkier organic molecules, e,g., C6Hs(CH2)2NH3+ (PEA+), CH3(CH2)3NH3+(n-BAT, iso-BA+), C2H4NH3 +, and polyethylenimine cations (PEI+), play an important role in the formation of low-dimensional perovskites. In this review, we review the recent development of low dimensional perovskites for solar cells application in terms of film preparation, photophysics, and stability of perovskites, as well as the related device structure and physics. We have also discussed the future development of low-dimensional perovskites from materials design, fabri- cation processes, and device structure.
基金The National Natural Science Foundation of China under contract No.42006129the Guangzhou Science and Technology Project under contract No.202102021228+2 种基金the National Key Research and Development Project of China under contract No.2021YFC3100500the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)under contract No.GML2019ZD0404the Special Research Assistant Grant Program of the Chinese Academy of Sciences.
文摘Although the adverse impacts of ocean acidification(OA)on marine calcifiers have been investigated extensively,the anti-stress capabilities regulated by increased light availability are unclear.Herein,the interactive effects of three light levels(30μmol photons/(m^(2)·s),150μmol photons/(m^(2)·s),and 240μmol photons/(m^(2)·s)combined with two pCO_(2)concentrations(400 ppmv and 1400 ppmv)on the physiological acclimation of the calcifying macroalga Halimeda opuntia were investigated using a pCO_(2)-light coupling experiment.The OA negatively influenced algal growth,calcification,photosynthesis,and other physiological performances in H.opuntia.The relative growth rate under elevated pCO_(2)conditions significantly declined by 13.14%−41.29%,whereas net calcification rates decreased by nearly three-fold under OA conditions.Notably,increased light availability enhanced stress resistance through the accumulation of soluble organic molecules,especially soluble carbohydrate,soluble protein,and free amino acids,and in combination with metabolic enzyme-driven activities,OA stress was alleviated.The carotenoid content under low light conditions increased markedly,and the rapid light curve of the relative electron transport rate was enhanced significantly by increasing light intensities,indicating that this new organization of the photosynthetic machinery in H.opuntia accommodated light variations and elevated pCO_(2)conditions.Thus,the enhanced metabolic performance of the calcifying macroalga H.opuntia mitigated OA-related stress.
基金supported by the National Natural Science Foundation of China(Nos.51873007,21835006,51961165102 and52003022).
文摘Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single-junction solar cells. Employing the wide bandgap perovskite materials and low bandgap organic materials as absorber layers for front and rear subcells, respectively, to construct perovskite/organic TSCs can complementarily absorb sunlight in ultraviolet-visible (UV-Vis) range by front perovskite and near-infrared (NIR) range by rear organic molecules, thus reducing the thermalization energy losses. Besides the subcells, the interconnection layer (ICL), which physically and electrically connects the front and rear subcells, is also an important tunnel junction to recombine charges. In this review, we summarize the optimization strategies of wide bandgap perovskites for front subcell, narrow bandgap organic material for rear subcell, and the ICLs employed in monolithic perovskite/organic TSCs.
基金Project supported by National Basic Research Program for China (Grant No 2006CB806000)Swedish Research Council, Carl Tryggers Stiftelse Foundation, Swedish International Development Cooperation Agency (SIDA)Natural Science Foundation of Shandong Province of China (Grant No Z2007A02)
文摘This paper investigates the dynamics of cooperative emissions in a cascade three-level system driven by an ultra, short laser pulse by solving numerically the full-wave Maxwell-Bloch equations. The 4, 4'-bis(dimethylamino) stilbene molecule is used as the model molecule because of its strong two-photon absorption property. The two-colour cooperative emissions are studied as functions of molecular number density and dephasing rate of the dipole coherence. The propagation effects on the evolution of the cooperative radiations are also taken into account. The cooperative radiations are enhanced for large number density of the molecule, while the fast dephasing of the dipole coherence reduces the intensity of the cooperative radiations and delays the emission times or even inhibits the formation of the emissions. The delay time of the radiation decreases with the increase of the molecular number density and the propagation distance.
基金Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 10904085)
文摘The influence of rotational isomerism on the two-photon absorption (TPA) of FTC chromophores has been investi- gated using the quadratic response theory with the B3LYP functional. Eight rotamers induced by three rotatable single bonds in the molecule are fully optimized, and it is found that their conformational energies are nearly degenerate. Our calculations demonstrate that rotational isomerism has an important effect on the TPA cross sections. For a certain rotamer, the maximum TPA cross section is enhanced significantly. In addition, in the longer wavelength region, the rotational isomerism could lead to a large shift of the TPA position.
文摘Aiming to reduce the defects of perovskite film and improve carrier transport,an organic small molecule,benzo[d]isothiazol-3(2H)-one 1,1-dioxide(OBS),is introduced as an additive in the solution-processing of perovskite and prepare uniform perovskite films with a continuous distribution of OBS at grain boundaries.Fourier trans-form infrared spectroscopy and X-ray photoelectron spectroscopy are conducted to reveal the interactions of hydrogen bonding and coordina tion bonding between OBS and perovskite.Various characterizations(including X-ray diffraction,UV-vis spectroscopy,electrochemical impedance spectroscopy,etc.)are conducted to uncover the effect of OBS on device performance.Consequently,high efficiency of 23.26%is obtained for the OBS-treated device,while the control device shows only a companion efficiency of 21.60%.
文摘During the mass formation of aggregates of molecules in a gelatin film dyed with the mixture of chrysophenine and acridine yellow dyes, photo-reorientation, photo-disorientation, and photo-orientation of the molecules are observed. Based on these observations, the photo-induction of granular aniso tropy may be realized.