Expanding the solvent diversity and perovskite compatibility of SnO inks that are directly deposited on perovskite layers.

Tin oxide (SnO) is an attractive electron transport material (ETM) for perovskite solar cells (PSCs) due to its optoelectronic properties, low-temperature solution processability, cost, and stability. However, solvent incompatibilities have largely limited its application to devices with SnO deposited below the perovskite. To expand its utility in other device structures, including inverted PSCs and tandem devices, alternate deposition strategies are needed.

Enhancing CO Capture via Metal-Ligand Cooperativity: Tuning Ligand Basicity and Zn(II) Lewis Acidity.

A series of thiosemicarbazonato-hydrazinatopyridine zinc(II) complexes were evaluated as direct air CO capture agents. The complexes sequester CO in a methanol solution as a metal-coordinated methylcarbonate. The reaction is reversible upon sparging of solutions with an inert gas (N or Ar).

Ligand and Linkage Isomers of Bis(ethylthiocarbamato) Copper Complexes with Cyclic CH Backbone Substituents: Synthesis, Characterization, and Antiproliferation Activity.

A series of isomeric bis(alkylthiocarbamate) copper complexes have been synthesized, characterized, and evaluated for antiproliferation activity. The complexes were derived from ligand isomers with 3-methylpentyl (HL) and cyclohexyl (HL) backbone substituents, which each yield a pair of linkage isomers. The thermodynamic products CuL have two imino N and two S donors resulting in three five-member chelate rings (555 isomers).

Two-Membrane Dual Non-Aqueous/Aqueous Electrolyte Flow Cell Operation for Electrochemical Conversion of CO to Methyl Formate.

Recently, tandem cathodic reactions have been demonstrated in non-aqueous solvents to couple CO reduction to a secondary reaction to create novel species that are not produced in aqueous CO electrolysis. One reaction that can be performed with high selectivity and durability is the electrochemical conversion of CO to formic acid and in-situ esterification with methanol to produce methyl formate. However, the translation to a high-performance flow electrolyzer is far from trivial, as the non-aqueous catholyte leads to reactor challenges including flooding the gas diffusion electrode.

Investigating BioCaRGOS, a Sol-Gel Matrix for the Stability of Heme Proteins under Enzymatic Degradation and Low pH.

There have been significant advances in the development of vaccines for the prevention of various infectious diseases in the last few decades. These vaccines are mainly composed of proteins and nucleic acids. Poor handling and storage, exposure to high temperatures that lead to enzymatic degradation, pH variation, and various other stresses can denature the proteins or nucleic acids present in any vaccine formulation.

Physical structure of constitutional isomers influences antiproliferation activity of thiosemicarbazone-alkylthiocarbamate copper complexes.

A series of hybrid thiosemicarbazone-alkylthiocarbamate copper complexes with similar electronic environments but distinct physical structures have been prepared, characterized, and evaluated for antiproliferation activity. The complexes include the constitutional isomers (1-phenylpropane-1-imine-(O-ethylthiocarbamato)-2-one-(N-methylthiosemicarbazonato))copper(II) (CuL) and (1-phenylpropane-1-one-(N-methylthiosemicarbazonato)-2-imine-(O-ethylthiocarbamato))copper(II) (CuL) along with (1-propane-1-imine-(O-ethylthiocarbamato)-2-one-(N-methylthiosemicarbazonato))copper(II) (CuL). Complexes CuL and CuL differ in the positions of the pendent thiosemicarbazone (TSC) and alkylthiocarbamate (ATC) moieties on the 1-phenylpropane backbone.

Metal-Ligand Cooperativity Promotes Reversible Capture of Dilute CO as a Zn(II)-Methylcarbonate.

In this study, a series of thiosemicarbazonato-hydrazinatopyridine metal complexes were evaluated as CO capture agents. The complexes incorporate a non-coordinating, basic hydrazinatopyridine nitrogen in close proximity to a Lewis acidic metal ion allowing for metal-ligand cooperativity. The coordination of various metal ions with (diacetyl-2-(4-methyl-thiosemicarbazone)-3-(2-hydrazinopyridine) (HL) yielded ML (M = Ni(II), Pd(II)), ML(CHOH) (M = Cu(II), Zn(II)), and [ML(PPh)]BF (M = Co(III)) complexes.

Enhancing the compatibility of BioCaRGOS silica sol-gel technology with ctDNA extraction and droplet digital PCR (ddPCR) analysis.

Previously, our group had demonstrated long term stabilization of protein biomarkers using BioCaRGOS, a silica sol-gel technology. Herein, we describe workflow modifications to allow for extraction of cell free DNA (cfDNA) from primary samples containing working concentrations of BioCaRGOS, as well as the compatibility of BioCaRGOS with droplet digital PCR (ddPCR) analysis for pancreatic cancer biomarkers , KRAS circulating tumor DNA (ctDNA). Preliminary attempts to extract ctDNA from BioCaRGOS containing samples demonstrated interference in the extraction of primary samples and the interference with ddPCR analysis when BioCaRGOS was directly introduced to stabilize sample extracts.

Ligand-Centered Hydrogen Evolution with Ni(II) and Pd(II)DMTH.

In this study, we report a pair of electrocatalysts for the hydrogen evolution reaction (HER) based on the noninnocent ligand diacetyl-2-(4-methyl-3-thiosemicarbazone)-3-(2-pyridinehydrazone) (HDMTH, HL). The neutral complexes NiL and PdL were synthesized and characterized by spectroscopic and electrochemical methods. The complexes contain a non-coordinating, basic hydrazino nitrogen that is protonated during the HER.

Investigations of Bis(alkylthiocarbamato)copper Linkage Isomers.

Linkage isomers are coordination compounds with the same composition but different donor atoms, resulting in distinct physical and electronic structures. A pair of linkage isomers, and , derived from phenylglyoxal bis(ethylthiocarbamate) were synthesized, isolated, and characterized by structural, electrochemical, and spectroscopic methods. The isomers are stable in solution under ambient conditions, but converts to in acid, consistent with quantum-chemical calculations.

The pH and Potential Dependence of Pb-Catalyzed Electrochemical CO Reduction to Methyl Formate in a Dual Methanol/Water Electrolyte.

The conversion of waste CO to value-added chemicals through electrochemical reduction is a promising technology for mitigating climate change while simultaneously providing economic opportunities. The use of non-aqueous solvents like methanol allows for higher CO availability and novel products. In this work, the electrochemistry of CO reduction in acidic methanol catholyte at a Pb working electrode was investigated while using a separate aqueous anolyte to promote a sustainable water oxidation half-reaction.

DNA-mediated hierarchical organization of gold nanoprisms into 3D aggregates and their application in surface-enhanced Raman scattering.

Colloidal crystallization using DNA provides a robust method for fabricating highly programmable nanoparticle superstructures with collective plasmonic properties. Here, we report on the DNA-guided fabrication of 3D plasmonic aggregates from polydisperse gold nanoprisms. We first construct 1D crystals DNA-induced and shape-directed face-to-face assembly of anisotropic gold nanoprisms.

Solvation of NiOfor hole transport layer deposition in perovskite solar cells.

A series of nickel oxide (NiO) inks, in the perovskite antisolvent chlorobenzene (CB) containing 15% ethanol, were prepared for the fabrication of p-i-n perovskite solar cells by blade coating. The inks included triethylamine (EtN) and alkyl xanthate salts as ligands to disperse NiOparticle aggregates and stabilize suspension. A total of four inks were evaluated: 0X (EtN with no alkyl xanthate), 4X (EtN + potassium-butyl xanthate), 12X (EtN + potassium-dodecyl xanthate), and 18X (EtN + potassium-octadecyl xanthate).

Antifungal activity of thiosemicarbazones, bis(thiosemicarbazones), and their metal complexes.

Fungi are ubiquitous in nature, and typically cause little or no environmental or pathogenic damage to their plant, animal, and human hosts. However, a small but growing number of pathogenic fungi are spreading world-wide at an alarming rate threatening global ecosystem health and proliferation. Many of these emerging pathogens have developed multi-drug resistance to front line therapeutics increasing the urgency for the development of new antifungal agents.

DNA-induced assembly of gold nanoprisms and polystyrene beads into 3D plasmonic SERS substrates.

The utilization of nanoparticle-polymer bead hybrid nanostructures as a SERS substrate depends on the control of the deposition, density, and distribution of nanoparticles on the bead surface. Here we demonstrate the fabrication of a large area SERS substate via a two- step DNA mediated assembly of gold nanoprisms and polystyrene (PS) beads into a large ensemble of beads that are densely coated with nanoprisms. First, nanoprisms are loaded on PS beads through DNA hybridization.

Exploiting Metal-Ligand Cooperativity to Sequester, Activate, and Reduce Atmospheric Carbon Dioxide with a Neutral Zinc Complex.

As atmospheric levels of carbon dioxide (CO) continue to increase, there is an immediate need to balance the carbon cycle. Current approaches require multiple processes to fix CO from the atmosphere or flue gas and then reduce it to value-added products. The zinc(II) catalyst Zn(DMTH) (DMTH = diacetyl-2-(4-methyl-3-thiosemicarbazonate)-3-(2-pyridinehydrazonato)) reduces CO from air to formate with a faradaic efficiency of 15.

Synthesis, Characterization, and Biological Activity of Hybrid Thiosemicarbazone-Alkylthiocarbamate Metal Complexes.

A series of hybrid ligands (-) derived from 4-methyl-3-thiosemicarbazide and hydrazinecarbothioic acid -alkyl esters were synthesized and characterized by NMR. The ligands were chelated with copper (-), nickel (-), and zinc (-) and characterized by spectroscopy, electrochemistry, and single crystal X-ray crystallography. The chelated metals displayed substantial anodic shifts in the Cu reduction potential of ∼160 mV relative to their bis(thiosemicarbazone) analogues.

Utilizing Charge Effects and Minimizing Intramolecular Proton Rearrangement to Improve the Overpotential of a Thiosemicarbazonato Zinc HER Catalyst.

The zinc(II) complex of diacetyl-2-(4-methyl-3-thiosemicarbazone)-3-(2-hydrazonepyridine), ZnL (), was prepared and evaluated as a precatalyst for the hydrogen evolution reaction (HER) under homogeneous conditions in acetonitrile. Complex is protonated on the noncoordinating nitrogen of the hydrazonepyridine moiety to yield the active catalyst Zn(HL)OAc () upon addition of acetic acid. Addition of methyl iodide to yields the corresponding methylated derivative ZnLI ().

Effect of Stacking Interactions on the Translation of Structurally Related Bis(thiosemicarbazonato)nickel(II) HER Catalysts to Modified Electrode Surfaces.

A series of crystalline nickel(II) complexes (-) based on inexpensive bis(thiosemicarbazone) ligands diacetylbis(4-methyl-3-thiosemicarbazone) (HATSM), diacetylbis(4,4-dimethyl-3-thiosemicarbazone) (HATSDM), and diacetylbis[4-(2,2,2-trifluoroethyl)-3-thiosemicarbazone] (HATSM-F) were synthesized and characterized by single-crystal X-ray diffraction and NMR, UV-visible, and Fourier transform infrared spectroscopies. Modified electrodes - were prepared with films of - deposited on glassy carbon and evaluated as potential hydrogen evolution reaction (HER) catalysts. HER studies in 0.

Photocatalytic hydrogen evolution on Si photocathodes modified with bis(thiosemicarbazonato)nickel(ii)/Nafion.

The molecular catalyst diacetyl-bis(N-4-methyl-3-thiosemi-carbazonato)nickel(ii) (NiATSM) was integrated with Si for light-driven hydrogen evolution from water. Compared to an equivalent loading of Ni metal, the NiATSM/p-Si electrode performed better. Durability of the surface-bound catalyst under operation in acid was achieved without covalent attachment by using Nafion binding.

Active uptake of hydrophilic copper complex Cu(ii)-TETA in primary cultures of neonatal rat cardiomyocytes.

Myocardial ischemia leads to copper efflux from the heart. The ischemic tissue with a low copper content fails to take up copper from the circulation even under the conditions of serum copper elevation. Cardiac copper repletion thus requires other available forms of this element than those currently known to bind to copper transport proteins.

Ligand-Assisted Metal-Centered Electrocatalytic Hydrogen Evolution upon Reduction of a Bis(thiosemicarbazonato)Ni(II) Complex.

In this study, we report the electrocatalytic behavior of the neutral, monomeric Ni(II) complex of diacetyl-bis( N-4-methyl-3-thiosemicarbazonato), NiL, for ligand-assisted metal-centered hydrogen evolution in acetonitrile (ACN) and dimethylformamide (DMF). Using foot-of-the-wave analysis (FOWA), NiL displays a maximum turnover frequency (TOF) of 4200 and 1200 s for acetic acid (CHCOOH) in ACN and DMF, whereas for trifluoroacetic acid (CFCOOH) the TOFs are 1300 and 120 s in ACN and DMF, respectively. In ACN, the overpotentials are 0.

Metal-Assisted Ligand-Centered Electrocatalytic Hydrogen Evolution upon Reduction of a Bis(thiosemicarbazonato)Cu(II) Complex.

In this study, we report the electrocatalytic behavior of the neutral, monomeric Cu(II) complex of diacetyl-bis(N-4-methyl-3-thiosemicarbazonato), CuL, for metal-assisted ligand-centered hydrogen evolution in acetonitrile and dimethylformamide. CuL displays a maximum turnover frequency (TOF) of 10 000 s in acetonitrile and 5100 s in dimethylformamide at an overpotential of 0.80 and 0.

Translation of Ligand-Centered Hydrogen Evolution Reaction Activity and Mechanism of a Rhenium-Thiolate from Solution to Modified Electrodes: A Combined Experimental and Density Functional Theory Study.

The homogeneous, nonaqueous catalytic activity of the rhenium-thiolate complex ReL (L = diphenylphosphinobenzenethiolate) for the hydrogen evolution reaction (HER) has been transferred from nonaqueous homogeneous to aqueous heterogeneous conditions by immobilization on a glassy carbon electrode surface. A series of modified electrodes based on ReL and its oxidized precursor [ReL][PF] were fabricated by drop-cast methods, yielding catalytically active species with HER overpotentials for a current density of 10 mA/cm, ranging from 357 to 919 mV. The overpotential correlates with film resistance as measured by electrochemical impedance spectroscopy and film morphology as determined by scanning and transmission electron microscopy.

Copper catalysed aerobic oxidation of benzylic alcohols in an imidazole containing N ligand framework.

The catalytic aerobic oxidation of benzylic alcohols to corresponding aldehydes has been investigated employing a tetradentate copper(ii) complex that incorporates N-methyl imidazole (NMI) as an integral part of an N-ligand framework. The complex [L-Cu] [(L = 1-methyl-4,5-dihydro-1H-imidazol-2-yl)methyl(2-ethyl)amine] has been synthesized, characterized by spectroscopic and structural techniques, and its catalytic activity towards the aerobic oxidation of benzylic alcohols studied under ambient conditions. Catalytic turnover required addition of the nitroxyl radical initiator TEMPO.