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A new solvothermal post-synthesis treatment for preparing high aspect ratio magnesium aluminium layered double hydroxides (MgAl–LDHs) has been developed. Treating laurate-intercalated MgAl–LDHs in pure ethanol in an autoclave for 48 h at 150 °C was found to produce delaminated MgAl–LDH nanosheets with a thickness of ∼2.6 nm and an aspect ratio of ∼105. It is proposed that the high pressure solvothermal process promotes the insertion of ethanol molecules into the LDH interlayer space, thereby facilitating delamination. This new post-synthesis treatment provides the opportunity for a facile, large scale route to highly delaminated high aspect ratio LDHs, which might be of interest towards novel nanomaterials for energy conversion and storage.

Rac- and meso-bis(1-hexamethylindenyl)phenylborane zirconium dichloride, {rac-, meso-( Ph BBI*)ZrCl 2 } has been synthesised and fully characterised. The slurry phase ethylene polymerisation performance of rac-( Ph BBI*)ZrCl 2 immobilised on a range of methylaluminoxane (MAO)-modified, solvent-dispersed, high surface area layered double hydroxides (AMO/AIM-Mg x Al-CO 3 LDHs) have been studied. The polymerisation activities show a strong dependence on the nature of the LDH. Rac-( Ph BBI*)ZrCl 2 supported on a MAO-modified 1-hexanol dispersed [Mg 0.73 Al 0.27 (OH) 2 ][CO 3 ] 0.135 LDH displayed a maximum ethylene polymerisation activity of 6641 kg PE mol Zr−1 h −1 bar −1 at 70 °C and 2 bar ethylene. Benchmarking studies reveal that some of the rac-( Ph BBI*)ZrCl 2 supported catalysts outperform a range of commonly used industrial metallocene PE catalysts.

Recently, the Innovation Team of Energy-Water-Air (ITEWA) from Shanghai Jiao Tong University has carried out researches on direct air capture of CO2. A new family of amine functionalized DAC adsorbent was reported by impregnating branched polyethyleneimine onto mixed metal oxide nanosheets, which exhibits excellent CO2 adsorption capacity (2.27 mmol/g) and kinetics (1.1 mmol/g∙h) under 400 ppm CO2 as well as good thermal stability and hydrothermal stability with almost no performance degradation after 20 adsorption cycles (DOI: 10.1039/D0TA05079B). On this basis, a three-step steam-assisted temperature vacuum swing adsorption (S-TVSA) cycle was designed for DAC (DOI: 10.1016/j.rser.2020.110651). Simulation results show that the S-TVSA cycle could capture CO2 at a rate of 4.45 mol/kg·day. By using novel adsorbents with better adsorption capacities and kinetics, the capture rate can be further increased by 280% and the energy consumption reduced to 32.8%.

We report a novel NH3-SCR catalyst Cu0.5Mg1.5Mn0.5Al0.5Ox synthesized from layered double hydroxides with superior activity in a wide temperature range and improved SO2 and H2O resistance comparing to conventional doped Mn/γ-Al2O3. This catalyst results in a high NOx removal efficiency of 87.0–96.6% in the low temperature range of 100–250 °C, much better than Mn/γ-Al2O3 (35.0–67.2%). Besides, it exhibits significant resistance to SO2 and H2O due to the existence of Cu and Mg. The promoting effects of Cu and Mg are thoroughly investigated using various physico-chemical techniques. The superior NH3-SCR activity of Cu0.5Mg1.5Mn0.5Al0.5Ox catalyst can be associated with its high specific surface area, high reducibility of MnO2 and CuO species, abundance of acid sites, and the well dispersion of MnO2 and CuO species. The interactions between SO2 and NH3, and the degradation mechanism caused by SO2 were investigated using in-situ DRIFT analysis.

Summary New types of cation storage materials would show tremendous potential in the development of high-performance rechargeable energy storage devices. Herein, we develop layered double hydroxides (LDHs) as promising cation supercapacitor materials in aqueous and neutral operation, via an effective electrochemical activation strategy, for a reversible intercalation of a wide range of metal cations. These activated LDH materials exhibit overwhelming metal-ion storage capacities in aqueous electrolytes as a result of the phase transformation of LDH (repulsive to cations) to hydrogen-vacancy-enriched LDH (LDH-HV, attractive to cations) induced by the electrochemical activation process. The activated LDH-HV phase provides a two-dimensional open channel with abundant active sites (HV) for a reversible intercalation of metal ions, accounting for the significantly enhanced energy storage performance. This vacancy-induced cation intercalation into LDHs builds up a general approach for developing earth-abundant transition-metal resources as a prospective energy storage material toward a large variety of cation supercapacitors.

Although there are many reports on the removal of NO x from vehicle and power plant emissions, little effort has been devoted to the removal of NO x from cracker flue gases. Here we report a systematic investigation on the design of highly efficient NO x storage-reduction (NSR) catalysts using highly dispersed aqueous miscible organic-layered double hydroxides (AMO-LDHs) derived mixed oxides (LDOs) for NO x emission control from naphtha cracker flue gases. For a series of binary M 2+ Al 3+ LDOs, the influence of six divalent cations (Ca, Zn, Cu, Ni, Co, and Mg) on the NO x adsorption capacity, NO oxidation property, and the thermal stability of adsorbed NO x was systematically investigated. The optimal NO x storage temperature range for each binary LDO was also determined. Based on the fundamental findings of binary LDOs, a ternary LDH CoMgAl-CO 3 derived LDO CoMgAlO x with a significantly improved NO x storage capacity was designed. By tuning the Co/Mg ratio, the NO x storage capacity was greatly improved from 0.14 mmol/g for Mg 3 Al 1 O x to 0.50 mmol/g for Co 1 Mg 2 Al 1 O x at 300 °C. By further doping Pt and K 2 CO 3 , a new NSR catalyst composed of 1 wt% Pt/15 wt% K 2 CO 3 /Co 1 Mg 2 Al 1 O x was obtained, which exhibited a very high NO x storage capacity of 1.2 mmol/g. Finally, the NSR cycling performance, and the CO 2 , SO 2 and H 2 O resistance of this catalyst were also investigated. Thanks for its superior NO x storage capacity, NSR cycling performance, and CO 2 , SO 2 and H 2 O resistance, this new NSR catalyst showed great potential for the NO x control from cracker flue gases.

Carbon dioxide (CO 2 ) capture using magnesium oxide (MgO)-based adsorbents at intermediate temperatures has been regarded as a very prospective technology for their relatively high adsorption capacity, low cost, and wide availability. During the past few years, great effort has been devoted to the fabrication of molten salts-modified MgO-based adsorbents. The extraordinary progress achieved by coating with molten salts greatly promotes the CO 2 capture capacity of MgO-based adsorbents. Therefore, we feel it necessary to deliver a timely review on this type of CO 2 capturing materials, which will benefit the researchers working in both academic and industrial areas. In this work, we classified the molten salts-modified MgO adsorbents into four categories: (1) homogenous molten salt-modified MgO adsorbents, (2) molten salt-modified double salts-based MgO adsorbents, (3) mixed molten salts-modified MgO adsorbents, and (4) molten salts-modified MgO-based mixed oxides adsorbents. This contribution critically reviews the recent developments in the synthetic method, adsorption capacity, reaction kinetics, promotion mechanism, operational conditions and regenerability of the molten salts-modified MgO CO 2 adsorbents. The challenges and prospects in this promising field of molten salts-modified MgO CO 2 adsorbents in real applications are also briefly mentioned.

Molecular orbital (MO) theory is used to describe the bonding in transition metal pentalene complexes in a variety of its coordination modes. The various MO models account for structural parameters and lead to simple rules for electron counting in pentalene complexes. Recent applications of pentalene complexes are also reviewed, in the areas of small molecule activation and catalysis and as molecular models for conducting organometallic polymers.

Layered double hydroxides (LDHs) are effective molecular carriers in cytological research, gene therapy, and transgenic applications. Herein, we investigated the internalization behavior of the LDH-DNA bioconjugates via a microscopic approach and analyzed the internalization pathway by dissipative particle dynamics (DPD) simulations. We experimentally found that LDH can efficiently carry DNA into the nucleus of cell in BY-2 suspension cells. Furthermore, atomic force microscopy and X-ray diffraction analysis demonstrated that the LDH-DNA bioconjugates mainly exist as a DNA-LDH-DNA sandwich complex, while the LDH-DNA-LDH sandwich complex and DNA-LDH complex cannot be excluded. The DPD simulations further indicated that only the DNA-LDH-DNA sandwich structure could penetrate the plasma membrane (PM), while PM is impermeable to the LDH-DNA-LDH sandwich complex and the DNA-LDH complex. This work provides novel perspective for understanding the membrane penetration mechanism of LDH nano-sheets and new insights into the design of novel molecular delivery systems.

We report here the synthesis of two new ansa-bridged permethylindenyl zirconocenes, their reaction with solid polymethylaluminoxane (sMAO) and their use in slurry phase ethylene polymerisation. Meso-(EBI*)Zr(CH2Ph)2 and meso-(EBI*)Zr(CH2tBu)Cl, (EBI* = ethylenebis[1-(2,3,4,5,6,7-hexamethylindenyl)]) were synthesised from meso-(EBI*)ZrCl2 and KCH2Ph and LiCH2tBu respectively. The new zirconocenes were characterised by NMR spectroscopy and X-ray crystallography, and density functional theory calculations were carried out. Solid precatalysts were obtained when these compounds were reacted with the polymethylaluminoxane support. Ethylene polymerisation activities of up to 6000 kgPE/molZr/h/bar were obtained in the slurry polymerisation of ethylene. The polyethylenes showed molecular weights, Mw, above 200 000 kg/mol and low polydispersities, Mw/Mn

Six new peralkylated bis(indenyl) zirconocene complexes have been synthesised and fully characterised; rac-­Me2SB(3-­EtI*)ZrX2 and meso-­Me2SB(3­-EtI*)ZrX2 (X = Cl, Br and CH2Ph). Solution-phase ethylene polymerisation using rac-Me2SB(3-­EtI*)ZrCl2/methylaluminoxane (MAO) and slurry-phase ethylene polymerisation using rac-Me2SB(3­-EtI*)ZrCl2 immobilised on solid polymethylaluminoxane (sMAO), MAO modified layered double hydroxide (LDHMAO) and MAO modified silica (SSMAO) were studied. Polymerisation conditions were optimised for sMAO-rac-Me2SB(3-­EtI*)ZrCl2 and applied to the other catalysts. A 75:25 mixture of rac-­ and meso-Me2SB(3­-EtI*)Zr(CH2Ph)2 supported on sMAO showed the highest polymerisation activities (4832 kgPEmolZr−1 h−1 bar−1 at 60 °C), producing high density polyethylenes (HDPE) with modest molecular weights (Mw of 336 kg mol−1 at 60 °C) and molecular weight distributions (Mw/Mn) less than 3.2. sMAO-rac-Me2SB(3-­EtI*)ZrCl2 was found to be responsive to H2 in a high-throughput screening system, producing polyethylenes with low molecular weights (Mw of 41 kg mol−1 with 1.6% H2). In the same high-throughput system, slurry-phase ethylene polymerisation in the presence of 1-hexene comonomer was shown to increase the polymerisation activity of sMAO-rac-Me2SB(3-­EtI*)ZrCl2) compared to polymerisation in the same system without 1-hexene.

A series of bis(peralkylindenyl)zirconocene and hafnocene complexes were synthesised and characterised by NMR spectroscopy, mass spectrometry and elemental analyses. 3-ethyl-2,4,5,6,7-pentamethylindanone, ( 3-Et Ind # [Formula presented] 3-ethyl-2,4,5,6,7-pentamethylindene, ( 3-Et Ind # )H, and rac-3-ethyl-2,4,5,6,7-pentamethylindenylhafnium dichloride, rac-( 3-Et Ind # ) 2 HfCl 2 , were also characterised by X-ray crystallography. rac- and meso-( 3-Et Ind # ) 2 MCl 2 (M = Zr or Hf) were obtained from the reaction of ( 3-Et Ind # )Li with ZrCl 4 or HfCl 4 . The group 4 metallocenes were then reacted with methylaluminoxane-functionalised silica (SSMAO) to afford silica supported catalysts. A mixture of rac- and meso-( 3-Et Ind # ) 2 ZrCl 2 supported on SSMAO demonstrated an initial polymerisation activity of 250 kg PE /mol M /h/bar. At 70 °C, using rac-( 3-Et Ind # ) 2 ZrCl 2 , solution phase polymerisation activities were twenty times faster than slurry phase polymerisation using SSMAO-rac-( 3-Et Ind # ) 2 ZrCl 2 (1243 and 75 kg PE /mol Zr /h/bar respectively).

A newly developed in situ monochromatic high-energy X-ray diffraction setup was used to investigate the synthesis of MOFs using cation-impregnated polymer resin beads as a ion source. The Co–NDC–DMF (NDC=2,6-naphthalenedicarboxylate; DMF=dimethylformamide) system was investigated, a system which is known to produce at least three distinct frameworks. It was found that the resin-assisted synthesis results in the preferential formation of a topology previously impossible to synthesise in bulk, while the comparable nitrate-salt synthesis appeared to form an alternative phases. It was also found that the resin-assisted synthesis is highly diffusion-controlled.

A family of group 4 metallocene complexes based on the hexamethylindenyl ligand (C9Me6H; Ind#) have been prepared and fully characterised. The complexes rac- Ind 2 # ZrCl2 (rac-1), meso- Ind 2 # ZrCl2 (meso-1), rac- Ind 2 # HfCl2 (rac-2), meso- Ind 2 # HfCl2 (meso-2) were prepared by the reaction of Ind#Li with the corresponding MCl4 (where M = Zr, Hf); and rac- Ind 2 # Zr(CH2Ph)2 (rac-3) was derived from rac-1 using two equivalents of potassium benzyl (KCH2Ph). All five species were characterised by NMR spectroscopy, single crystal X-ray diffraction and studied using density functional theory. The zirconocenes were tested for their activity as solution-phase ethylene polymerisation catalysts and rac-1 was found to outperform the meso-1 at most temperatures. The benzyl analogue, rac-3, peaked at more than double the activity reported for the dihalide species.

Layered α-cobalt hydroxides Co(OH)1.65Cl 0.35·0.5H2O (1), Co(OH)1.75(NO 3)0.25·0.1H2O (2) with unique macro- and microscale morphologies have been synthesised by a low temperature, ammonia-controlled vapour-diffusion method. The materials have thin film morphologies and were characterized by X-ray powder diffraction (XRD) and field emission scanning electron microscopy (FESEM). © 2010 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences.

The carbonization behavior of surfactants templated within mesoporous silica is studied in detail. Cetyltrimethylammonium bromide and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123) are used as the structure-directing agents for MCM-41 and SBA-15 synthesis, respectively. Thermal treating the as made silica/surfactant composites under argon flow at 900 °C produces partially graphitized carbon filaments as a result of the carbonization of the surfactants within the mesopores. Furthermore, the carbon materials derived from P123 in SBA-15 yield a more developed graphite structure than the carbon obtained from CTAB in MCM-41, as evidenced by the narrower X-ray Bragg reflections in the powder XRD and larger IG/ID ratio in the Raman spectra. © 2006 Elsevier Ltd. All rights reserved.

Four organic phosphonate anions (methyl-, ethyl-, phenyl- and benzyl- (MPA, EPA, PPA, BPA)) were successfully intercalated into the [Ca 2 Al(OH) 6 ]NO 3 ⋅ y H 2 O ( y = 1 – 2 ) layered double hydroxide (LDH) by anion exchange. The materials have been characterised by a range of physical methods including powder diffraction, elemental microanalysis, infrared spectroscopy, thermal analysis and solid state NMR. The measured interlayer expansions upon intercalation of the aromatic phosphonates suggest that the guests are intertwined between the layers, while the aliphatic guests appear to be tilted with respect to the layers. The elemental microanalysis data for all four intercalates suggests there is a significant incorporation of some of the neutral phosphonic acid as well as the anion into the structure. Solid state 31 P NMR spectroscopy was employed to investigate the nature of the guest ions in some of these materials. In the MPA case, a single 31 P resonance was seen, lying at a chemical shift intermediate between the neutral and monovalent forms of MPA. This implies rapid proton exchange occurs between MPA units, giving an average charge of between 0 and −1 on all guests. In the PPA case, two resonances were seen, but the chemical shifts of these were consistent with the average charge on the PPA units being between −1 and −2. The reason for this is believed to be that rapid proton exchange is occurring between the PPA anions and the interlayer water molecules: this rationalises the observed results while maintaining local electroneutrality. In situ diffraction studies were performed in order to determine the rate of intercalation of the methyl-, phenyl- and benzylphosphonate guest ions, and to investigate the reaction mechanisms. In all three cases, the reactions are direct transformations from the host to the product. In general we observe that nucleation is rate determining, but in the methyl and phenyl cases the importance of nucleation declines with increasing temperature.

We report the first example of selective intercalation of nucleoside monophosphates in a layered host material. The intercalated nucleoside monophosphates can then be quantitatively recovered from the inorganic host and so this opens up the possibility of using simple layered inorganic hosts as rapid, cost effective and recyclable materials for the purification and separation of complex biomolecules.

A specially designed hydrothermal cell has been used for the study of the crystallisation of some zeolites from amorphous aluminosilicate gels by time-resolved in situ neutron diffraction. The effect of sodium hydroxide concentration and temperature has been investigated. Following the reactions in situ has allowed the stability of zeolite phases to be monitored directly and efficiently under real reaction conditions. At the lowest sodium hydroxide concentrations used and at the lowest temperature applied (80°C) sodium zeolite A is the favoured product and after a period in excess of 10 h is the sole product. As the sodium hydroxide concentration or temperature is increased the initially formed sodium zeolite A is replaced by hydroxosodalite. At 140°C hydroxosodalite crystallises directly from the amorphous gel. By determining the changing areas of Bragg reflections with time, crystallisation curves can be obtained. The advantages of the in situ powder neutron diffraction technique over analogous X-ray powder diffraction methods are discussed.

The synthesis of vanadium and molybdenum complexes derived from nitrogen-containing heterocyclic aromatic ligands are described. The first η-pyrazine sandwich complex, [V(η 6 -Me 4 pyrazine) 2 ], has been prepared by metal vapour synthesis and crystallographically characterized. The synthesis of [Mo(η 6 -2,6-lutidine) 2 ] has been substantially improved, and provides a convenient starting material for the preparation of the new half-sandwich compounds [Mo(η 6 -2,6-lutidine)(PMe 3 ) 3 ] and [Mo(η 6 -2,6-lutidine)(η 3 -allyl)Cl] 2 .

The photo-isomerisation of cis-azobenzene by light of wavelength 432 nm has been investigated by channel electrode voltammetry. In a lithium ethoxide/ethanol medium cis-azobenzene was found to be reduced at a more positive potential (ca. 120 mV) than the trans isomer in the dark at a gold electrode. Quantitative waveshape measurements, with the electrode illuminated, of current-voltage curves for the reduction of the cis isomer as a function of the rate of mass transport, reveal the partial conversion of cis to trans and enable the quantum yield for the cis to trans isomerisation to be found as φ = 0.21.

Single crystals of the 2-D layered host SnS 2−x Se x (x = 0, 0.3, 0.5, 1.3, 1.85 and 2) have been intercalated with cobaltocene {Co(ν-Cp) 2 ; Cp = C 5 H 5 }. The host materials are all semiconductors with activation energy (E a ) varying from 0.02 – 0.45 eV. The intercalates are all ca . 2 × 10 2 less resistive than the hosts, and the temperature dependence of their resistivities range from variable range hopping (VRH) semiconductors to superconductors [Tc = 6.1 K for SnSe 2 {Co( ν -Cp) 2 }0.3].

The surface decomposition mechanism of bistrimethylamine aluminium hydride [(Me3N)2 · AIH3] on the Ga-rich (4 × 1) GaAs (100) surface is studied by TDS, HREELS and XPS. It is found that the first monolayer of the complex chemisorbs molecularly at 150 K. The decomposition pathway is shown to involve the activated dissociation of this chemisorbed precursor to produce Al, adsorbed H atoms and trimethylamine. The latter species desorb without further fragmentation and this key feature results in the deposition of carbon-free aluminium films. This contrasts markedly with the decomposition of organometallics like trimethyl aluminium (TMA) which are traditionally used in Al CVD where carbon incorporation is an intrinsic part of the decomposition process.

The compound Mo(η-C5H4(CH2)2SPrn)2(SPrn)2 acts as a bidentate ligand giving the heteronuclear bi-metallic compounds [Mo(η-C5H4CH2CH2SPrn)2-(SPrn)2(PtCl2)],[Mo(η-C5H4CH2CH2SPrn)2(SPrn)2(PdCl2)2], [Mo(η-C5C4CH2CH2SPrn)2(SPrn)2(RhCl3)2], [Mo(η-C5H4CH2CH2SPrn)2(μ-SPrn)2Rh(dppe)]BF4, [Mo(η-C5H4CH2CH2SPrn)2(μ-SPrn)2(COD)Rh]Cl, [Mo(η-C5H4CH2CH2SPrn)2-(μ-SPrn)2Pt(PPh3)2](PF6)2, and the compound [Mo(η-C5H4(CH2)2-μ-SPh)2Cl2Rh(COD)]Cl bonds via the ring-sulphur substituents giving [Mo(η-C5H4(CH2)2-μ-SPh)2-Cl2Rh(COD)]Cl.

The compounds [Re(η 6 -C 9 H 8 )(η 5 -C 9 H 7 )] (major) and [Re(η 6 -C 9 H 10 )(η 5 -C 9 H 7 )] (minor) are formed by co-condensation of rhenium atoms with indene. [Re(η 6 -C 9 H 8 )(η 5 -C 9 H 7 )] can be reversibly protonated giving [Re(η 6 -C 9 H 8 )(η 5 -C 9 H 7 )H]BF 4 . [Re(η 6 -C 9 H 8 )(η 5 -C 9 H 7 )] is deprotonated by KH giving the compound K + [Re(η 6 -C 9 H 7 )(η 5 -C 9 H 7 )] − , which reacts with [Rh(η 3 -C 8 H 12 )Cl] 2 to form [Re(η 5 -C 9 H 7 )(μ 2 -η 6 :η 3 -C 9 H 7 )Rh(η 4 -C 8 H 12 )]; the first example of an η 3 :η 6 -indenyl ligand.

We report magnetic susceptibility ( ξ spin (T)) and magnetization measurements for single crystals of the compound decamethylferrocenium tetracyanoethanide, (DMeFc)(TCNE), with the needle axis oriented parallel and perpendicular to the applied field. Magnetic ordering studies carried out using neutron diffraction show enhancement' of the Bragg peaks at temperatures less than 4.8K. The susceptibility for 16 K