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With the rapid growth of solar energy, recycling and reuse of end-of-life solar modules have become a critical issue. In light of this, a simple, yet environmentally friendly, ball milling process was used to transform the recycled Si of waste solar cells into a lithium ion battery anode material. The ball-milled recycled Si was further combined with a carbon fiber paper (CP) substrate to fabricate a composite electrode. The milling time and rotation speed were optimized to form a Si/SiOx/Al2O3 active material with a moderate primary particle size, agglomeration extent, and oxidation states of Si and Al. These features allow the recycled Si to exhibit promising cycling and rate performances. Additionally, introducing a hydrothermally treated CP substrate can further improve the electrochemical performance of the composite electrode, delivering a high discharge capacity of 1603 mA h g-1 after 100 cycles (capacity retention of approximately 91% (200 mA g-1)) and 813 mA h g-1 at 2000 mA g-1, due to the presence of nitrogen-containing groups, particularly the pyridinic-N group. This is evidenced by the reduced solid electrolyte interface and charge transfer resistances and the increased ion diffusion coefficient of the Si/SiOx/Al2O3-based cell. [ABSTRACT FROM AUTHOR]

Two aryl amino borinium cations derived from Cl(Mes)B-NR2 (NR2 = TMP, HMDS) faced divergent outcomes. As the HMDS-substituted one underwent methyl migration from silicon to boron transforming the putative borinium ion to a silylium ion, [Mes-B-TMP]+ can initiate cyanosilylation and catalyse hydrosilylation of ketones and aldehydes. [ABSTRACT FROM AUTHOR]

A cyclotriveratrylene-based molecular cage forms hemicarceplexes that significantly increase the solubility of commercially available Sc3N@C80 in CDCl3. When incarcerated within the molecular cage, the two structural isomers of this metallofullerene, Sc3N@D5h-C80 and Sc3N@Ih-C80, displayed characteristic signals in both 1H and 13C NMR spectra, allowing direct identification of each isomer without the need to enrich the sample with 13C atoms. [ABSTRACT FROM AUTHOR]

A new ligand with N8O2 donors containing three potential metalbinding sites (H2L) and its tricopper(II) complex 1 are synthesized. The tricopper species is found to be formed from a hypodentate dicopper(II) complex 2 in basic solutions. Complex 2 may be isolated from the reaction of H2L with a copper source under acidic conditions. Complex 2 can undergo CO2-abstraction to yield an octacopper(II) complex 3. The single crystal structures of complexes 2 and 3 are characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Thermal reaction of 2,7-bis(2-pyridinyl)-l,8-naphthyridine (bpnp) with Ru3(CO)12 in the presence of moisture resulted in the formation of a formate-bridged diruthenium complex [(bpnp-H3)Ru2(μ-HCOO)- (CO)4] (1), in which the ligand was partially hydrogenated. Complex 1 was fully characterized by spectroscopic analyses and X-ray single crystal determination. Regarding the partially reduced ligand in 1, it occurs through a water-gas shift type reduction. The bridging formate ligand can be substituted by other carboxylate ligands. Physical and chemical properties of the newly prepared complexes were investigated [ABSTRACT FROM AUTHOR]

Thermal reaction of 2,7-bis(2-pyridinyl)-l,8-naphthyridine (bpnp) with Ru3(CO)12 in the presence of moisture resulted in the formation of a formate-bridged diruthenium complex [(bpnp-H3)Ru2(μ-HCOO)- (CO)4] (1), in which the ligand was partially hydrogenated. Complex 1 was fully characterized by spectroscopic analyses and X-ray single crystal determination. Regarding the partially reduced ligand in 1, it occurs through a water-gas shift type reduction. The bridging formate ligand can be substituted by other carboxylate ligands. Physical and chemical properties of the newly prepared complexes were investigated [ABSTRACT FROM AUTHOR]

In this study, we synthesized a series of bipolar hosts (CbzCBI, mCPCBI, CbzNBI, and mCPNBI) containing hole-transporting carbazole and electron-transporting benzimidazole moieties and then examined the morphological, thermal, and photophysical properties and carrier mobilities of these bipolar host materials. Altering the linking topology (C- or N-connectivity of the benzimidazole) changed the effective conjugation length and led to different excited-state solvent relaxation behavior. The N-connected compounds (CbzNBI, mCPNBI) possessed higher triplet energies (ET) than those of their C-connected analogues (CbzCBI, mCPCBI) by 0.23 eV. The higher values of ETof CbzNBIand mCPNBIendowed them with the ability to confine triplet excitons on the blue-emitting guest. A blue PhOLED device incorporating mCPNBIachieved a maximum external quantum efficiency, current efficiency, and power efficiency of 16.3%, 35.7 cd A−1, and 23.3 lm W−1, respectively; confirming the suitability of using N-connected bipolar hosts for the blue phosphor. The donor/acceptor interactions of the C-connected analogue resulted in a lower triplet energy, making it a suitable bipolar host for green phosphors. A green-phosphorescent device incorporating CbzCBIas the host doped with (PBi)2Ir(acac) achieved a maximum external quantum efficiency, current efficiency, and power efficiency of 20.1%, 70.4 cd A−1, and 63.2 lm W−1, respectively. [ABSTRACT FROM AUTHOR]

A molecular cage-based complex, in which the complexed guest changes its binding geometry with respect to the macrocyclic host upon the addition and removal of K+ions, is reported. [ABSTRACT FROM AUTHOR]

Cationic methylpalladium complexes with hemilabile bidentate ligands of α-amino-pyridines, in the form of {[R1HNCR2H(o-C6H5N)]Pd(Me)(NCMe)}(BF4) (R1= iPr, tBu, Ar R2= H, Me) have been found to be effective precursors for catalytic copolymerization of ethylene and norbornene under mild conditions. The copolymer products exhibit predominant alternating microstructures which are evidenced by NMR and mass spectrometry as well as a kinetic analysis according to the Finman-Ross relationship. [ABSTRACT FROM AUTHOR]

Ethylene polymerization catalyzed by Ni(II) complexes that bear new bidentate ligands with a functional hybrid of amine and imine has been studied. A class of new α-aminoaldimines and their nickel complexes [R1R2NCMe2CH=N(2,6-R32C6H3)]NiBr2 (R1 = R2 = Me, R3 = Me (Ni-1b); R3 = iPr (Ni-1c); 1 = R2 = Et, R3 = H (Ni-2a); Me (Ni-2b); iPr (Ni-2c); R1 = R2 = nPr, R3 = iPr (Ni-3c); (R1R2) = c-C3H6 R3 = tPr (Ni-4c); (R1R2) = c-C4H8, R3 = iPr (Ni-5c)) were synthesized. The molecular structures of six nickel complexes were determined by X-ray crystallography, showing distorted tetrahedral configurations. The SQUID data of Ni-1c confirms its ground state of triplet spin. Using methylaluminoxanes (MAO) as the activator, the nickel complexes are found to catalyze ethylene polymerization under moderate pressure and ambient temperature. The activity reaches to 106 g PE mol Ni-1 h-1, and increases with the ethylene pressure in the range of 14-28 bar. The highly branching PE products have Mn ∼ 105 with PDI < 2. The amine and imine functionalities demonstrate independent control to the polymerization reactions, wherein the activity appears to be facilitated by using the catalysts installed with bulky imino substituents as well as with less sterically hindered amino substituents. This is ascribed to the C2 unsymmetric coordination in the square planar resting state in which the bulky polymer chain prefers cis to the imine and the small ethylene monomer is cis to the amine. [ABSTRACT FROM AUTHOR]

New α-aminoaldimines with the formula of Et2NCMe2CHNR (R = iPr, tBu, Ph) and their dichloro or diacetato complexes of Ni, Pd, Pt are prepared and structurally characterized. A nickel complex is in a distorted tetrahedral configuration, and the Pd and Pt complexes (4–6) are of square planar form. The α-aminoaldimines can chelate to the metal in a C2-unsymmetric bidentate motif through the hetero functionalities of amine and imine, which show comparable transinfluence. Square planar organometallic palladium derivatives bearing α-aminoaldimines, including Pd–methyl, Pd–acetyl, and Pd–(η2-acetylnorboryl) (7–10), are also synthesized. The latter two species are a result of CO-insertion into Pd–methyl complexes and ensuing norbornene-insertion, respectively. The geometrical isomerism is found in the transconfiguration in most studied cases. Such a stereoselectivity results from the thermodynamic stability governed predominantly by steric control. The stereoselectivity is also supported by DFT calculations. [ABSTRACT FROM AUTHOR]

An unusual, honeycomb-like cadmium-tri-thiocyanate polymeric framework was found in the studied hybrid material of general formula (L2+)n[Cd(SCN)3]2n2n−(3), where L2+ is bis[4-(N-benzylpyridinium)]piperazine dication. The perforated coordination net forms due to a template effect of the organic dications which reside in the holes penetrating the net in a polyrotaxane-like manner. The salt (L2+)(SCN)2·2H2O (4) was studied for comparison. [ABSTRACT FROM AUTHOR]

Two new polymorphs (C and D) of [t-Fe(abpt)2(NCS)2] are characterized, a commensurate modulated structure with the c axis tripled in the thermally quenched metastable high spin state at 25 K is found in polymorph C. [ABSTRACT FROM AUTHOR]

Two new polymorphs (C and D) of [t-Fe(abpt)2(NCS)2] are characterized, a commensurate modulated structure with the caxis tripled in the thermally quenched metastable high spin state at 25 K is found in polymorph C. [ABSTRACT FROM AUTHOR]

The Z → E photoisomerization and fluorescence quantum yields for the wild-type green fluorescence protein (GFP) chromophore (p-HBDI) and its meta- and para-amino analogues (m-ABDI and p-ABDI) in aprotic solvents (hexane, THF, and acetonitrile) and protic solvents (methanol and 10–20% H2O in THF) are reported. The dramatic decrease in the quantum yields on going from aprotic to protic solvents indicates the important role of solvent–solute hydrogen bonding in the nonradiative decay pathways. The enhanced fluorescence of m-ABDI is also discussed. [ABSTRACT FROM AUTHOR]

We have used the “threading-followed-by-swelling” approach to fix a daisy chain structure in solution, leading to the isolation of a captured [c2]daisy chain in 77% yield. [ABSTRACT FROM AUTHOR]

We describe a [2]rotaxane molecule that exhibits distinct signals in its 1H NMR spectra upon the complexation of physiologically important Li, Na, Mg2 and Ca2 ions; thus, the identification of these metal ions in solution is possible from the analysis of a single 1H NMR spectrum of a single molecular sensor. [ABSTRACT FROM AUTHOR]

2,7-Bis(4-tert-butylphenyl)-9,9′-spirobifluorene exhibits balanced electron and hole mobilities of up to 10−3cm2V−1s−1, as measured using time-of-flight techniques. [ABSTRACT FROM AUTHOR]

A new ligand with N8O2 donors containing three potential metalbinding sites (H2L) and its tricopper(II) complex 1 are synthesized. The tricopper species is found to be formed from a hypodentate dicopper(II) complex 2 in basic solutions. Complex 2 may be isolated from the reaction of H2L with a copper source under acidic conditions. Complex 2 can undergo CO2-abstraction to yield an octacopper(II) complex 3. The single crystal structures of complexes 2 and 3 are characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Two new polymorphs (C and D) of [t-Fe(abpt)2(NCS)2] are characterized, a commensurate modulated structure with the c axis tripled in the thermally quenched metastable high spin state at 25 K is found in polymorph C. [ABSTRACT FROM AUTHOR]