Spin and dielectric transitions promoted by dimerization of anionic radical stacks and volume-conserving motion of cations in an ion-pair compound.

Demonstrating the mechanism of a structural phase transition (SPT) is significantly important for guiding the precise design of new phase transition materials. Herein, an ion-pair compound [DPIm][Ni(mnt)] (1, DPIm = 1,3-dipropylimidazolium and mnt = maleonitriledithiolate) has been obtained and thoroughly characterized through microanalysis, spectral, and thermal analysis techniques. The [Ni(mnt)] anions form columnar stacks, featuring one-dimensional (1D) = ½ spin chains.

Topotactic Conversion of Titanium-Oxo Clusters to a Stable TOC-Based Metal-Organic Framework with the Selective Adsorption of Cationic Dyes.

Titanium-oxo cluster (TOC)-based metal-organic frameworks (MOFs) have received considerable attention in recent years due to their ability to expand the application of TOCs to fields that require highly stable frameworks. Herein, a new cyclic TOC formulated as [TiO(OPr)(TTFTC)(phen)] (, where TTFTC = tetrathiafulvalene tetracarboxylate and phen = phenanthroline) was crystallographically characterized. TOC takes a rectangular ring structure with two phen-modified Ti clusters as the width and two TTFTC ligands as the length.

Redox-Active Two-Dimensional Tetrathiafulvalene-Copper Metal-Organic Framework with Boosted Electrochemical Performances for Supercapatteries.

Metal-organic frameworks (MOFs) have attracted noticeable attention as promising candidates for electrochemical energy storage. However, the lack of electrical conductivity and the weak stability of most MOFs result in poor electrochemical performances. Here, a tetrathiafulvalene (TTF)-based complex, formulated as [(CuCN)(TTF(py))] () (TTF-(py) = tetra(4-pyridyl)-TTF), is assembled by in situ generation of coordinated CN from a nontoxic source.

Oxidatively Doped Tetrathiafulvalene-Based Metal-Organic Frameworks for High Specific Energy of Supercapatteries.

Poor electrical conductivity and instability of metal-organic frameworks (MOFs) have limited their energy storage and conversion efficiency. In this work, we report the application of oxidatively doped tetrathiafulvalene (TTF)-based MOFs for high-performance electrodes in supercapatteries. Two isostructural MOFs, formulated as [M(py-TTF-py)(BPDC)]·2HO (M = Ni (), Zn (); py-TTF-py = 2,6-bis(4'-pyridyl)TTF; HBPDC = biphenyl-4,4'-dicarboxylic acid), are crystallographically characterized.

Photocurrent and Gelation Properties of Polyphenol-Modified Titanium-Oxo Compounds.

Organic-inorganic hybrid metal-polyphenols as stable structural modules have gained extensive interest due to their diverse applications. However, titanium-oxo compounds (TOCs) with large molecular polyphenols have been less explored, and they were expected to be different from small polyphenols with isolated metal ions. Herein, 4-methyl-esculetin (Mesc), a catechol derivative, was selected to construct three TOCs, namely, [TiO(Mesc)(OPr)] (), [TiO(OPr)][TiO(Mesc)(OPr)] (), and [TiO(Mesc)(OAc)(OPr)] ().

A Convenient Procedure for Preparing BiOX-TiO Photoelectrocatalytic Electrodes from a Titanium-Oxo Compound-Modified Carbon Fiber Cloth.

Photoelectrocatalysis (PEC) has shown great advantages in sustainable organic synthesis and wastewater treatment because the PEC process can minimize electron-hole recombination, thereby improving the photocatalytic performance. Here, we report a convenient procedure for preparing immobilized BiOX-TiO photoelectrocatalytic electrodes from a titanium-oxo compound (TOC)-modified carbon fiber cloth (CFC). Crystalline TOCs composed of Ti cations and bismuth halide anions, [TiO(OPr)][BiBr(THF)] () and [TiO(OPr)][BiI(THF)] (), were grown on CFC.

A Cyclic Titanium-Oxo Cluster with a Tetrathiafulvalene Connector as a Precursor for Highly Efficient Adsorbent of Cationic Dyes.

Titanium-oxo clusters (TOCs) have been studied for applications in catalysis, energy storage and transfer, light emission, and so on; however, use of TOCs for the selective adsorption of dyes has not yet been reported. Herein, a TOC compound formulated as [TiO(OPr)(TTFTC)] (, TTFTC = tetrathiafulvalene-tetracarboxylate) was successfully prepared and crystallographically characterized. Compound has a cyclic structure assembled by four Ti clusters and four rodlike TTFTC connectors.

Tetrathiafulvalene-Cobalt Metal-Organic Frameworks for Lithium-Ion Batteries with Superb Rate Capability.

Although pristine metal-organic framework (MOF) anodes for lithium-ion batteries (LIBs) show moderate activities and relatively stable cycling, the poor rate capability of the MOF anodes limited their applications in the development of a new generation of energy storage. Herein, the electric active Co ion is selected to coordinate with redox-active S-rich tetrathiafulvalene (TTF) derivatives to create two TTF-Co-MOFs, formulated as [Co(py-TTF-py)(BDC)]·2DMF·HO (TTF-Co-MOF ) and [Co(py-TTF-py)(BPDC)]·3DMF·3HO (TTF-Co-MOF ), where py-TTF-py = 2,6-bis(4'-pyridyl)tetrathiafulvalene, HBDC = terephthalic acid, HBPDC = biphenyl-4,4'-dicarboxylic acid, and DMF = ,-dimethylformamide. Crystallographic characterization indicated that the two MOFs possess similar 2-fold-interpenetrating 3D frameworks but with two different pore sizes.

Copper-bipyridine grid frameworks incorporating redox-active tetrathiafulvalene: structures and supercapacitance.

Redox active tetrathiafulvalene (TTF) and its derivatives when used as electrode additives have exhibited improved energy efficiency and sustainability in batteries. However, the structure-property relationship has not been investigated in detail until very recently. In this work, three redox-active TTF compounds were synthesized, and formulated as [Cu(HL)(bpa)] (1), [Cu(bpe)(HO)]·2n(HL)·nMeOH·nHO (2), and [Cu(bpp)(HO)]·2n(HL) (3) (L = dimethylthio-tetrathiafulvalene-bicarboxylate) for this work.

Mono- and Bismetalphenanthroline-Substituted Ti Clusters: Structural Variance and the Effect on Electronic State and Photocurrent Property.

Despite the numerous titanium-oxo clusters (TOCs) which have been reported, the nature of small clusters (nuclearity < 10) as model compounds showed large deviation from that of nanoscale TiO materials. Therefore, theoretical and experimental studies for large TOCs merit more attention. We recently prepared and crystallographically characterized a series of large TOCs: TiO(OPr)(Cophen) (), TiO(OPr)(Mnphen) (), TiO(OEt)(Mnphen) (), and TiO(OEt)(Mnphphen) () (phen = 1,10-phenanthroline, phphen = 4,7-biphenyl-phen).

Assembly of a Titanium-Oxo Cluster and a Bismuth Iodide Cluster, a Single-Source Precursor of a p-n-Type Photocatalyst.

Titanium oxides and bismuth halides or oxyhalides have been known to be excellent semiconductors with both excellent photocatalytic and photoelectric properties. The design of supersalts assembled by titanium-oxo clusters (TOCs) and bismuth iodide clusters is a hopeful strategy for exploring the chemistry and application of new titanium-oxo clusters. We report herein a series of unusual ionic TOCs with Ti oxo cluster cations and bismuth iodide anions, [TiO(OPr)][BiI] (Bi), [TiO(OPr)][BiI(THF)] (Bi), and [TiO(OPr)][TiBiO(OPr)][BiI] (Bi).

2D Lead Iodide Perovskite with Mercaptan-Containing Amine and Its Exceptional Water Stability.

Two dimensional (2D) hybrid perovskites have attracted a great deal of interest because of their appropriate photovoltaic efficiency and environmental stability. Although some 2D hybrid perovskites with sulfur-containing amines have been reported, the cation having the mercaptan group has not been well explored yet. In this work, cysteamine (Cya, HS(CH)NH), a mercaptan-containing amine, was introduced into 2D hybrid perovskite.

Tetrathiafulvalene-based double metal lead iodides: structures and electrical properties.

Introducing electronically active organic components into lower dimensional metal halide compounds is an effective strategy to improve the electronic properties of hybrid metal halide materials. We have previously used this strategy to explore hybrid halides with tetrathiafulvalenes (TTFs) and a series of lead iodides and bismuth halides were isolated. The electronic properties were improved notably using this modification.

Tetrathiafulvalene-Based Metal-Organic Framework as a High-Performance Anode for Lithium-Ion Batteries.

Metal-organic frameworks (MOFs) have aroused great interest as lithium-ion battery (LIB) electrode materials. In this work, we first report that a pristine three-dimensional tetrathiafulvalene derivatives (TTFs)-based zinc MOF, formulated [Zn(py-TTF-py)(BDC)]·2DMF·HO () (py-TTF-py = 2,6-bis(4'-pyridyl)tetrathiafulvalene and HBDC = terephthalic acid), can work as a high-performance electrode material for rechargeable LIBs. The TTFs-Zn-MOF electrode displayed a high discharge specific capacity of 1117.

Hybrid Lead Iodide Perovskites with Mixed Cations of Thiourea and Methylamine, From One Dimension to Three Dimensions.

Hybrid halide perovskites featuring as new materials of high-performance solar cells have attracted great research interest. The temperature-dependent dimensional transition of halide perovskites is a crucial handle in the preparation of perovskite films. Only the small cations of methylammonium (MA) or formamidinium (FA) have been involved for most of the dimensional transition materials.

Molybdenum-titanium oxo-cluster, an efficient electrochemical catalyst for the facile preparation of black titanium dioxide film.

Black-TiO has become increasingly interesting as a promising photoactive material. Most of the preparations for black-TiO involve either high temperature calcination, plasma, lengthy chemical reactions or dealing with dangerous or toxic chemicals. We found, by accident, that Mo-Ti oxo-clusters are efficient catalysts for the hydrogenation of a TiO electrode to black-TiO at room temperature.

Cobalt Metal-Organic Frameworks Incorporating Redox-Active Tetrathiafulvalene Ligand: Structures and Effect of LLCT within the MOF on Photoelectrochemical Properties.

Understanding the effect of charge transfer on the physical properties of metal-organic frameworks (MOFs) is essential for designing multifunctional MOF materials. In this work, three redox-active tetrathiafulvalene (TTF)-based MOFs, formulated as [CoL(bpe)(EtOH)(MeOH)(HO)]·5HO (), [Co(μ-OH)L(bpe)] (), and [CoL(bpa)(HO)]·2HO () (L = dimethylthio-tetrathiafulvalene-bicarboxylate, bpe = 1,2-bis(4-pyridyl)ethene, bpa = 1,2-bis(4-pyridyl)ethane), are crystallographically characterized. Complexes and are two-dimensional (2D) coordination polymers, and features an unusual three-dimensional (3D) MOF.

Eu-phen Bonded Titanium Oxo-Clusters, Precursors for a Facile Preparation of High Luminescent Materials and Films.

Incorporation of Eu complexes into various organic or inorganic matrixes is one of the acceptable strategies to obtain displaying materials having practical applications. In this work, we report a convenient approach to preparing high luminescent organic-inorganic hybrid materials and films from the europium-titanium oxo-clusters (EuTOCs) having photoactive antenna ligands. Three EuTi oxo-clusters were synthesized and crystallographically characterized.

A Series of Tetrathiafulvalene Bismuth Chlorides: Effects of Oxidation States of Cations on Structures and Electric Properties.

Most large organic cations in the low-dimensional hybrid halide perovskites deteriorate the photoelectric conversion efficiency of the cells. Integrating electronically active organic components into hybrid metal halides is an effective method to improve their photoelectric properties. In this work, a series of compounds obtained by hybridizing redox-active tetrakis(methylthio)tetrathiafulvalene (TMT-TTF) with bismuth chloride, formulated as [TMT-TTF][BiCl] ( and ), [TMT-TTF][BiCl] (), [TMT-TTF][BiCl] (), [TMT-TTF][BiCl] (), and {[TMT-TTF][BiCl]} (), were crystallographically characterized.

A Potential Hybrid Hole-Transport Material Incorporating a Redox-Active Tetrathiafulvalene Derivative with CuSCN.

Inorganic CuSCN and organic tetrathiafulvalene derivatives (TTFs) have been exploited as hole-transport materials (HTM) in hybrid perovskite solar cells. To develop new HTM, we herein report two hybrid materials incorporating redox-active TTFs with CuSCN framework (TTFs-CuSCN). Single-crystal analysis showed that compound [Cu(py-TTF-py)(SCN)] () is three-dimensional (3D) and compound [Cu(py-TTF-py)(SCN)] () is two-dimensional (2D) (py-TTF-py = 2,6-bis(4'-pyridyl)tetrathiafulvalene).

Water-Soluble Lanthanide-Titanium-Oxo Cluster, a Precursor for Biocompatible Nanomaterial.

Titanium-oxo clusters (TOCs) are attractive as a rapidly growing class of molecular materials due to their use as molecular models and precursors of nano-titanium-oxide. However, most TOCs can only be dissolved in nonaqueous solvents, which largely limits their potential applications in biological or environmental situations. Very few water-soluble TOCs were reported, which can be used directly in aqueous biomedical systems.

Bio-compatible fluorescent nano TiO materials prepared from titanium-oxo-cluster precursors.

Photoactive nano TiO2 particles with fluorescent properties have attracted great attention because of their potential applications in photodynamic therapy. Herein we report first a simple method to prepare water soluble fluorescent nano titanium oxide particles from titanium-oxo-clusters (TOCs). The nano material was characterized as an aggregate of titanium-oxo-clusters, which can be used directly in aqueous systems for investigations in biomedical fields.

A Series of Ti Oxo Clusters Anchored with Arylamine Dyes: Effect of Dye Structures on Photocurrent Responses.

Dye molecules pre-anchored on titanium oxo clusters (dye-TOCs) are attractive as model compounds of dye-sensitized titanium oxide. To investigate the effects of the dye ligand structures of the dye-TOCs on photocurrent conversion, a series of dye-TOCs with the same Ti core structure and different antenna ligands (L) was synthesized and characterized crystallographically. The TOCs have the same structural formula of [Ti O L (O PPh) (OiPr) ].

Molecular Model of Dye Sensitized Titanium Oxides Based on Aryl-Amine Dye Anchored Titanium Oxo Clusters.

Model studies on dye sensitized titanium oxides have attracted wide interest with respect to their importance in understanding photoelectric and photophysical processes. Ligand modified titanium oxo clusters (TOCs) have been considered as the most appropriate models for dye sensitized solar cells (DSSCs) on the basis of their atomically precise structures. However, the ligands used previously in TOC models were seldom the dyes that really applied in DSSCs due to the difficulty with which the crystals of the dye anchored TOCs are obtained.

Effects of the Ligand Structures on the Photoelectric Activities, a Model Study Based on Titanium-Oxo Clusters Anchored with S-Heterocyclic Ligands.

Titanium oxo clusters (TOCs) have become one of the worldwide hot research topics because they are excellent molecular TiO materials having unique photoactive properties and can been used as models of dye-sensitized solar cells (DSSCs). S-Heterocyclic ligands such as thiophene (Th) and tetrathiafulvalene (TTF) derivatives have been widely used in electronic or photoelectronic devices and solar cells. However, a study of the synthesis and properties of TOCs anchored with Th and TTF derivatives is missing.