Interfacial engineering through lead binding using crown ethers in perovskite solar cells

In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications.

Third-Order Nonlinear Optical Responses of Bis(15-crown-5)-stilbenes Binding to One-or Two-Alkali Metal Cation(Li^(+),Na^(+)and K^(+))

Bis(15-crown-5)-stilbenes containing crown ether parts have been widely used in a variety of chemical applications,such as cation detectors,because of their ability to selectively bind to alkali metal cations,Bis(15-crown-5)-stilbenes and its derivatives with complexation of one-or two-alkali metal cation(Li^(+),Na^(+)and K^(+))have been theoretically investigat-ed by quantum chemistry methods.The coordination of alkali cations results in partial shrinkage of crown ethers,which directly affected natural distribution analysis charges and molecular orbital energy levels.The number of alkali metal ions has significant effects on absorption spectra and mean second hyperpolarizability.When one alkali metal ion was added to the anticonformer of bis(15-crown-5)-stilbene,the absorption spectra were obvious-ly redshifted and the mean second hyperpolarizability values were slightly increased;while two alkali metal ions were added to bis(15-crown-5)-stilbene,the absorption spectra were ob-viously blue shifted and the mean second hyperpolarizability values decreased.On the other hand,as the radius of the alkali ions increased,the mean second hyperpolarizability values of the compounds increased gradually.It is indicated that the mean second hyperpolarizability value is sensitive to the number and radius of the alkali metal cations,thus the third order nonlinear optical response can be used as a signal to detect the number and type of alkali met-al ions.

Bis Crown Ethers( Ⅸ)——Caesium Selective PVC Membrane Electrodes Based on Schif f Base Type of Bis Crown Ethers

Recently, much attention has been focused on the use of neutral carrier species as membrane components to extract ions from aqueous solution into a hydrophobic membrane phase. Some potassium-or caesium-selective electrodes based on bis-benzo-15-crown-5 or bis-benzo-18-crown-6 containing ester or other linkage were prepared by K. Kimura and K. W. Fung. The selective coefficients K;, K;,or K;, K were 2.6×10;, 1.9×10;and 1.7×10;, respectively.

Molecular Design of Crown Ethers. 19~1. Synthesis of Novel Disulfide and Diselenide-Bridged Bis (benzo-12-crown-4)s and their Ag^+ Selective Electrode Properties

Two novel heteroatom-bridged his (benzo-12-crown-4 ether)s, i.e. his [2-nitro-4,5 (1,4,7,10-tetraoxadecamethylene) disulfide 1 and diselenide 2, have been synthesized. X ray crystallographic structure was obtained for 1. Ion selective electrodes (ISE) for Ag+, containing 1 and 2 in PVC membrane as neutral carriers, were prepared, and their selectivity coefficients for Ag^+ (K_(Ag.M)^(pot)) were determined against other heavy metal ions, alkali and alkaline-earth metal ions. and ammonium ion. These ISEs showed excellent Ag^+ selectivities, log K_(Ag.M)^(pot) ≤ -3.8, against most of the interfering canons examined, except for Hg^+.

Synthesis of New Bis-diphenyl-22-and Diphenyl-11-Membered Ring N-pivot lariat Crown Ethers

Bis diphenyl 22 and 11 Membered Ring N pivot lariat Crown Ethers were prepared by one step reaction of 2,2' dihydroxy diphenyl with N tosyl diethanolamine ditoskylate in DMF at refluxing tem perature under N z,Using anhydrous potassium carbonate as condensing agent,respectirely.The tosyl group of(1,2) were removed by treatment with 40%HBr in AcoH in the presence gf a large amount of phenol to give correspondence crown ether compounds(3,4).New N pirot lariat crown thers(5,6)were prepared by one step reaction of(3)with RBr(R=-CH 2CH=CH 2,-CH 2(CH 2) 14 CH 3) in CH 3CN at refluxing temperature under N 2,Using anhydrous K 2CO 3 as condensing agent.New N pivot lariat croon ether(7) were prepared by one step reaction (4)with n bromohexadecane in CH 3CN at refluxing temperature under N 2, Using anhydrous potassium carbonate as condensing agent.New compounds(1,3,5,6,7)were characterized by IR,, 1H NMR,Ms and elemental analysis.

STUDIES ON COMPLEXES OF RARE EARTHS WITH CROWN ETHERS(V)-SYNTHESIS AND CHARACTERIZATION OF THE COMPLEXES OF RARE EARTH NITRATES WITH 2,2'-DINITRO-4,5,4',5'-BIS-(15-CROWN-5)-DIBENZO DISULFIDE

Three new solid complexes of macrocyclic polyether ligand 2, 2'-dinitro-4, 5, 4', 5'bis-(15- crown-5)-dihenzo disulfide(L) with trivalent rare earth nitrates having composition of RE(NO_3)_3·L ·6H_2O(RE=Ce, Pr, Nd) have been synthesized in acetonitrile. All the isolated complexes have been characterized by elementary analysis, IR and UV spectra, differential thermal and thermogravimetric analysis, X-ray powder diffraction analysis, molar conductance and measurements of solubility in some general solvents.

Bibracchial Lariat Ethers(Ⅰ)——The Synthesis and Crystal Structure of the N,N'-bis(2-Methoxy-1-Naphthylmethyl)-4,13-Diaza-18-Crown-6 Sodium Iodide Complex

Diaza Crown ethers are versatile complexing reagents, their complexing abilities are dramatically modified by the electron donating atoms on substituents attached to the nitrogen if they can give a three-dimensional cavity as in cryptates. Hence the synthesis and characterization of bibracchial lariat ethers (BIBLES) have received much attention. In the preparation of new BIBLES, a complex Ⅱ was unexpectedly obtained.

Convenient synthesis of aryl-incorporated ditosylates and their application in preparation of crown ethers with higher yield

A convenient synthetic method with high yields for aryl-incorporated ditosylates by reaction of aryl-incorporated diols with TsCI in THF/NaOH/H2O solution was described. Some of these aryl-incorporated ditosylates reacted with diphenols to produce crown ethers in pleasant yield.

Microwave-assisted fast and efficient synthesis of some crown ethers

13-Crown-4, 16-crown-5, dibenzo-12-crown-4 and dibenzo-14-crown-4 were synthesized by a one-pot microwave-assisted procedure in good yields. Irradiation of diols and dichlorides in the presence of sodium hydroxide in DMSO gave title crown ethers presumably within a template effect. ？2009 Hossein Eshghi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

Suppressing Li Dendrites via Electrolyte Engineering by Crown Ethers for Lithium Metal Batteries

Electrolyte engineering is considered as an effective strategy to establish stable solid electrolyte interface(SEI),and thus to suppress the growth of lithium dendrites.In a recent study reported in Advanced Functional Materials by Ma group,discovered that strong coordination force could be founded between 15-Crown-5 ether(15-C-5) and Li+,which facilitates the crown ether(15-C-1) to participate in the solvation structure of Li+ in the electrolyte for the same purpose.Such a novel strategy might impact the design of highperformance and safe lithium metal batteries(LMB s).

Studies on the Synthesis and Complexing Behavior of Crown Ethers with External Coordination Center

The synthesis, characterization of five ditopic or tritopic crown compounds were reported in this paper together with the preparation of the corresponding hetero-dinuclear and hetero-trinuclear complexes with different metal cations.

Study on Molecular Recognition of Crown Ethers to Aniline and Monosaccharides

Theoretical study on coordinates between crown ethers and aniline as well as monosaccharides is performed by AM1, MNDO and PM3 methods. It is indicated that crown ethers possess ability to recognize polar guests especially ionic guests and monosaccharides. Electronic spectra of coordinates are computed by the INDO/SCI method. The reason of the blue-shift for UV absorption of complexes relative to that of hosts is discussed and electronic transition is theoretic- cally assigned.

Density Functional Theory Study of Selectivity of Crown Ethers to Li^+ in Spent Lithium-Ion Batteries Leaching Solutions

It is a challenge to recover lithium from the leaching solution of spent lithium-ion batteries,and crown ethers are potential extractants due to their selectivity to alkali metal ions.The theoretical calculations for the selectivity of crown ethers with different structures to Li ions in aqueous solutions were carried out based on the density functional theory.The calculated results of geometries,binding energies,and thermodynamic parameters show that 15C5 has the strongest selectivity to Li ions in the three crown ethers of 12C4,15C5,and 18C6.B15C5 has a smaller binding energy but more negative free energy than 15C5 when combined with Li^+,leading to that the lithium ions in aqueous solutions will combine with B15C5 rather than 15C5.The exchange reactions between B15C5 and hydrated Li^+,Co^2+,and Ni^2+were analyzed and the results show that B15C5 is more likely to capture Li^+from the hydrated ions in an aqueous solution containing Li^+,Co^2+,and Ni^2+.This study indicates that it is feasible to extract Li ions selectively using B15C5 as an extractant from the leaching solution of spent lithium-ion batteries.

Synthesis of New Aza-crown Ethers Containing Pyridine Ring and their Liquid Membrane Transport of Alkali Cations

Five new aza-crown ethers have been prepared by the condensation of 2,6-bis[(2-formylphenyl)oxymethyl] pyridine with different diamino compounds in hot methanol, the bis-Schiff bases without isolation were reduced with NaBH4 to afford the corresponding aza-crown ethers. The liquid membrane transport or alkali cations using the five new macrocycles as the ion-carriers was also studied.

On an Expression of Extraction Constants without the Interfacial Equilibrium-Potential Differences for the Extraction of Univalent and Divalent Metal Picrates by Crown Ethers into 1,2-Dichloroethane and Nitrobenzene

An idea on interfacial equilibrium-potential differences () which are generated for the extraction of univalent metal picrate (MPic) and divalent ones (MPic2) by crown ethers (L) into high-polar diluents was improved. These potentials were clarified with some experimental extraction-data reported before on the M = Ag(I), Ca(II), Sr(II) and Ba(II) extraction with 18-crown-6 ether (18C6) and benzo-18C6 into 1,2-dichloroethane (DCE) and nitrobenzene (NB). Consequently, it was demonstrated that the? values from the extraction-experimentally obtained logKD,Pic ones are in agreement with or close to those calculated from charge balance equations in many cases, where the symbol, KD,Pic, denotes an individual distribution constant of Pic﹣ into the DCE or NB phase. Also, it was experimentally shown that extraction constants based on the overall extraction equilibria do not virtually contain the? terms in their functional expressions.

Extraction of Cesium from the Irradiated Nuclear Waste by 4(5),4'(5')-Bis[1-hydroxyalkylbenzo]-21-crown-7

Bis[1-hydroxyalkylbenzo]-21-crown-7 (A-C) have been synthesized by ) two-step reactions from dibenzo-21-crown-7 (DB21C7). Extraction of cesium cation from nitric acid solutions by A-C has been investigated in nitromethane. Under the conditions of various concentration of HNO3 or NaNO3, the extractabilities of A and B were superior to that of DB21C7.

SILICA-BOUND CROWN ETHERS PLATINUM COMPLEX AS HYDROSILYLATION CATALYST

Silica-bound 15-Crown-5, 18-Crown-6 with a spacer of propyloxymethyl and their platinum complexes have been synthesized. It was found that they were efficient catalysts for the hydrosilylation of olefms with triethoxysilane in the temperature range of 60 to 130 ℃.

Synthesis and Properties of New-type Troponoid Dithio-Crown Ethers

Condensation of 3,7-dichloromethyl-5-isopropyl-2-methoxytropane 4 with bis (mercaptoethyl) ether 5a and mono, di, and tri-ethylene glycol bis(mercaptoethyl) ethers 5b-5d gave troponoid-annexed dithiocrown ethers 6a-6d. Compounds 6a-6d have selective and reversible mercury salt capturing ability.

Spectral Properties of Extracted Complexes of MetalPicrates with Crown Ethers

The investigation on UV-visible spectra of species formed by extracting some metal picrates with benzo-15-crown-5(B15C5) and dibenzo-18-crown-6(DB18C6) verified that there are some interactions of picrate anion with K+, Na+ and rare earth ions in loaded organic phase. By the study of the charge transfer band and absorption spectra of picrate anion, it can be determined whether an ion pair has been formed and either a 1 : 1 contact ion pair or a 1 : 2 crown-separated ion pair involved in organic phase can be distinguished for an ion-pair extraction.

Liquid Membrane Transport Behavior of Functional Substituted Crown Ethers for Amino Acids

Three functional substituted crown ethers were synthesized as liquid membrane transport carriers for amino acids. The result obtained shows that this kind of ditopic ligands can transport sodium salt of amino acids in good rate value especially the one with two pyridinyl groups as binding site outside the macrocycle.