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Few spin-crossover materials with a 1D ladder-type structure have been reported. Previously, [Fe(Mebpt){Au(CN)2}]·H2O (MebptH = 3-(5-methyl-2-pyridyl)-5-(2-pyridyl)-1,2,4-triazole) was made and shown to display gradual spin-crossover behaviour. In the current work, a new 1D iron(II) ladder-type compound, [Fe(bpt){Au(CN)2}] (bptH = 3-(2-pyridyl)-5-(2-pyridyl)-1,2,4-triazole), was produced and showed enhanced spin-crossover behavior. It showed an abrupt spin transition above room temperature with a 3 K hysteresis (T1/2↓ = 335 K and T1/2↑ = 338 K). The origin of its enhanced spin-crossover could be ascribed to a greater influence of supramolecular interactions over the electronic substituent effect.

A novel BiOBr@TiO2/carbon hybrid framework as a continuous flow sunlight water purification system has been reported in the present work. The BiOBr@TiO2/carbon hybrid framework was fabricated via the sequential growth of TiO2 nanowires and BiOBr nanoplates on carbon fiber cloth. TiO2 nanowires interweaved with carbon fibers to form a porous network, while BiOBr nanoplates were arrayed on TiO2 nanowires. The obtained BiOBr@TiO2/carbon hybrid framework possesses numerous micro/nanochannels between their adjacent one-dimensional building blocks, which can serve as an effective water transport network driven by capillary force. Furthermore, BiOBr@TiO2/carbon hybrid frameworks exhibit impressive sunlight-driven photocatalytic activity and adsorption ability because of their enhanced sunlight absorption ability, efficient charge separation features, and mesoporous architecture. The excellent reusability and durability of the BiOBr@TiO2/carbon hybrid frameworks have also been confirmed. A novel BiOBr@TiO2/carbon hybrid framework based continuous flow sunlight water purification system with a high water purification efficiency (305.6 L h-1 m-2) has been constructed in the present work. All the features make the BiOBr@TiO2/carbon hybrid framework a promising material suitable for water purification.

A new kind of self-standing CuO@TiO 2 nanowires (NWs) film with hierarchical feature was prepared by a three-step protocol consisting of hydrothermal reaction, electroless plating, and branched growth processes. This heterostructured CuO@TiO 2 NWs film demonstrates the favorable physical properties in the photoelectrochemical cell (PEC) water splitting, such as the hierarchical surface, the extended optical absorption range, and the rapid interface charge transfer kinetics. Under the illumination of the simulated solar light, the pristine TiO 2 NWs film only attains a photocurrent density of 0.12 mA/cm 2 at 1.0 V versus reversible hydrogen electrode (RHE). Significantly, the CuO@TiO 2 NWs film can yield a dramatically increased photocurrent density of 0.56 mA/cm 2 at the same applied voltage. Furthermore, amperometric I–t tests of the CuO@TiO 2 NWs film reveal satisfactory stability. All the above characteristics of this heterostructured CuO@TiO 2 NWs film indicate its great potential in the water splitting applications with solar visible light.

Spin-crossover clusters with iron(II) high nuclearity are rare. By using 3,5-bis(pyridin-2-yl)-1,2,4-triazole (bptH) as the ligand with two bidentate chelating sites, we successfully obtained three pentanuclear iron(II) cluster helicate compounds [{FeII(μ-bpt)3}2FeII3(μ3-O)][FeII2(μ-Br)(μ-bpt)(NCS)4(H2O)]·2H2O·C2H5OH (1), [{FeII(μ-bpt)3}2FeII3(μ3-O)][FeII2(μ-bpt)2(NCS)4] (2), and [{FeII(μ-bpt)3}2FeII3(μ3-O)]I2·2C2H5OH (3). Research on single-crystal structure and magnetism has indicated that tuning the spin state of two iron(II) ions in axial direction is successfully realized by regulating the different counter anions: one apical [FeII(bpt)3]− unit exhibits spin-crossover behavior while the other [FeII(bpt)3]− unit remains in low spin state in 1, both apical ions are of high spin states in 2, and are of low spin states in 3.

Through the precoating of TiO2 on carbon fiber sheet and the subsequent hydrothermal reaction of the coated species with NaOH and tetrabutyl titanate, we successfully demonstrated the engineering growth of TiO2 nanofibers on carbon fiber sheet. The resulting cloth exhibits excellent flexibility and enables robust, large-area (∼300 cm2) fabrication, representing a significant advantage over previous brittle, small area nanofibrous macroscopic structures. The adsorption and photodecomposition of Rhodamine B in water showed that the resulting cloth is very convenient for the purification of contaminated water owing to its combined adsorption and cleaning function. This work provides new insight into the construction of a large area, flexible and robust water purification membrane material.

The solvothermal reactions of Zn(NO3)2∙6H2O with 1,4-benzenedicarboxylic acid (1,4-H2bdc) and 1,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)butane (dmpzb) or 1,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)hexane (dmpzh) afforded two three-dimensional coordination polymers [Zn3(1,4-bdc)3(dmpzb)]n (1) and [Zn2(1,4-bdc)2(dmpzh)]n (2), respectively. Compounds 1 and 2 were characterized by elemental analysis, IR, powder X-ray diffraction, and single crystal X-ray diffraction. Compound 1 has an 8-connected 3D net (a 364185262 Schlafli symbol) assembled from trinuclear [Zn3(1,4-bdc)3] units and 1,4-bdc and dmpzb bridges. Compound 2 has a 6-connected 3D net (with a 485463 Schlafli symbol) constructed from binuclear [Zn2(1,4-bdc)2] units and 1,4-bdc and dmpzh linkers. The solid state luminescent and thermal stability properties of 1 and 2 at ambient temperature were also investigated. The results showed that the spacer lengths of bipyrazol-based ligands did affect the topological structures of zinc(II) coordination polymers.

We report a one-pot route to the formation of free-standing, large-area CNTs/TiO 2 nanofiber membrane with enhanced photocatalytic activity. Tetra- n -butyl titanate was reacted with NaOH to form high-quality titanate nanofibers with diameters below 200 nm and longitudinal dimensions of several tens of micrometers. CNTs were condensed with the as-prepared nanofibers and enabled the nanofibers to assemble into a free-standing membrane. It is proposed that the CNTs act as linkers between the nanofibers, and it is crucial for the formation of the membrane under the hydrothermal conditions. Benefiting from the introduction of CNTs, the as-prepared nanofiber membrane exhibited higher photocatalytic activity than pure TiO 2 nanofibers.

A novel BiOBr@TiO

Solvothermal reactions of LnCl3·6H2O (Ln = Nd, Eu, Yb) with equimolar amounts of 5,11,17,23-tetrakis[(m-carboxyphenyl)azo]-25,26,27,28-tetrahydroxycalix[4]arene (H4L) at 90 or 140 °C gave rise to a set of six lanthanide(III) coordination polymers {[Nd2ClL(HCOO)(DMF)3(H2O)]·0.5DMF·MeCN·1.5H2O}n (1), {[Ln2ClL(HCOO)(DMF)]·sol}n (2: Ln = Eu, sol =0.5MeCN·1.5H2O; 3: Ln = Yb, sol = 1.5H2O), and {[H3O][LnL(H2O)]·DMF·MeCN·H2O}n (4: Ln = Nd; 5: Ln = Eu; 6: Ln = Yb). Complexes 1–6 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Compounds 1–3 have two-dimensional (2D) networks in which [Nd6Cl4L2(DMF)12(H2O)2] units (1) or [Ln6Cl4L2(DMF)2] (Ln = Eu (2), Yb (3)) are interlinked by the carboxyl groups of formates. Compounds 4–6 exhibit 2-fold interpenetrating 2D networks in which each [Ln4L(H2O)4] “four-flier pinwheel” unit works as a planar eight-connecting node to connect its eight equivalents via four L ligands. The formation of 1–6 provided an interestin...

Treatment of [Et(4)N][Tp*WS(3)] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 2 equiv of AgSCN in MeCN afforded a novel neutral compound [(Tp*WS(2))(2)(μ-S(2))] (2). Reactions of 2 with excess CuX (X = Cl, Br, I) in MeCN and CH(2)Cl(2) or CHCl(3) formed three neutral W/Cu/S clusters [{Tp*W(μ(3)-S)(3)Cu(3)(μ-Cl)}(2)Cu(μ-Cl)(2)(μ(7)-Cl)(MeCN)](2) (3), [{Tp*W(μ(3)-S)(3)Cu(3)}(2)Br(μ-Br)(2)(μ(4)-Br)(MeCN)] (4), and [{Tp*W(μ(3)-S)(3)Cu(3)}(2){Cu(2)(μ-I)(4)(μ(3)-I)(2)}] (5), respectively. On the other hand, treatment of 2 with CuX (X = Cl, Br) in the presence of Et(4)NX (X = Cl, Br) produced two anionic W/Cu/S clusters [Et(4)N][{Tp*W(μ(3)-S)(3)Cu(3)X}(2)(μ-X)(2)(μ(4)-X)] (6: X = Cl; 7 X = Br). Compounds 2-7 were characterized by elemental analysis, IR, UV-vis, (1)H NMR, electrospray ionization (ESI) mass spectra, and single-crystal X-ray crystallography. The dimeric structure of 2 can be viewed as two [Tp*WS(2)] fragments in which two W atoms are connected by one S(2)(2-) dianion. Compounds 3-7 all possess unique halide-bridged double cubanelike frameworks. For 3, two [Tp*W(μ(3)-S)(3)Cu(3)](2+) dications are linked via a μ(7)-Cl(-) bridge, two μ-Cl(-) bridges, and a [Cu(MeCN)(μ-Cl)(2)](+) bridge. For 4, one [Tp*W(μ(3)-S)(3)Cu(3)(MeCN)](2+) dication and one [Tp*W(μ(3)-S)(3)Cu(3)Br](+) cation are linked via a μ(4)-Br(-) and two μ-Br(-) bridges. For 5, the two [Tp*W(μ(3)-S)(3)Cu(3)](2+) dications are bridged by a linear [(μ-I)(2)Cu(μ(3)-I)(2)Cu(μ-I)(2)](4+) species. For 6 and 7, two [Tp*W(μ(3)-S)(3)Cu(3)X](+) cations are linked by a μ(4)-X(-) and two μ-X(-) bridges (X = Cl, Br). In addition, the third-order nonlinear optical (NLO) properties of 2-7 in MeCN/CH(2)Cl(2) were investigated by using femtosecond degenerate four-wave mixing (DFWM) technique.

Through the precoating of TiO2 on Ni foam and the subsequent hydrothermal reaction of the coated species with NaOH and tetrabutyl titanate, we successfully demonstrated the engineered growth of TiO2 nanofibers on the NiO–Ni foam. The adsorption and photodecomposition of Rhodamine B in water showed that the resulting foam is very convenient for the purification of contaminated water. Selective permeability of Au nanoparticles of different sizes revealed that the modified foam possesses size-dependent separation functionality.