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• 7440-70-2 calcium 
• 7440-21-3 silicon 
• 112926-00-8 silica gel 
• 14336-71-1 calcium chloride 

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• 75-54-7 Dichloromethylsilane 
• 75-77-4 chloro-trimethyl-silane 
• 75-79-6 Methyltrichlorosilane 
• 10026-04-7 tetrachlorosilane 

Relevant academic research and scientific papers

Hydriding and dehydriding properties of CaSi

The hydriding and dehydriding properties of CaSi were investigated both theoretically and experimentally. First-principles calculations suggested that CaSiHn is thermodynamically stable. Experimentally, the p -c isotherms clearly demonstrated plateau pressures in a temperature range of 473-573 K and the maximum hydrogen content was 1.9 weight % (wt.%) under a hydrogen pressure of 9 MPa at 473 K. The structure of CaSiHn is different from those of ZrNi hydrides, although CaSi has the CrB-type structure as well as ZrNi.

Can one design zintl anions? Contributions from the system Sr/Mg/Si to the topic Si2-

Two novel ternary suicides, SrMgSi2 (Pnma, Z = 8, a = 14.374, b = 4.4512, c = 11.398 ?) and Sr11Mg2Si10, (C2/m, Z = 2, a = 19.744, b = 4.754, c = 14.84 ?, β = 112.47°) have been established in the ternary system Sr/Mg/Si. The compounds are synthezised from the elements under inert conditions. Single crystal structure determinations yield the novel Zintl anions, ∞1[Si(Si3)8-] a branched chain, and the zig-zag chain piece [Si8]18-, both of which exhibit significant correlations and differences with respect to the linear chains in ∞1[Si-] in the binary MSi phases (M = Ca, Sr, Ba) which have been reinvestigated in this context. The variations of the Zintl anions can be traced back mainly to the differences of Mg-Si and Sr-Si interactions. From these findings a functional relationship between Mg content and the formation of endgroup members in Zintl anions of silicon is anticipated. Johann Ambrosius Barth 1996.

Structure and Properties of Hydrogenated Ca, Sr, Ba, and Eu Silicides

The binary metal suicides CaSi, BaSi, SrSi, and EuSi that crystallize in the CrB type absorb reversibly hydrogen. Hydrogen contents of the products were measured by the carrier gas hot extraction method (CaSiHx: 1.56 wt %, x ≈ 1.06; SrSiHx

Size controlled mechanochemical synthesis of ZrSi2

Mechanochemical metathesis reactions were utilized to synthesize nanocrystalline ZrSi2 ranging from 9-30 nm in size. Size was controlled through dilution with CaCl2. A linear relationship was found between diluent concentration and crystallite size. Unlike typical self-propagating metathesis reactions, this reaction did not self-propagate, requiring the input of mechanical energy.

Synthesis and crystal structures of Ca4SiN4 and NEW POLYMORPH of Ca5Si2N6

Single crystals of Ca4SiN4 were found in the product prepared by heating Ba, Ca, Si, NaN3, and Na at 900 C. Ca 4SiN4 [space group P21/c (No. 14), Z = 4, a = 9.1905(4) A, b = 5.9775(3) A, c = 11.0138(7) A, β = 116.4054(17) ] is isotypic with Ca4GeN4 and K 4SiO4. Isolated [SiN4]8- tetrahedra were identified in the structure by single-crystal X-ray diffraction. After reheating the product at 900 C, a new polymorph of Ca5Si 2N6 crystallized. The space group of the polymorph [C2/m (No. 12), Z = 4, a = 6.2712(5) A, b = 10.0175(8) A, c = 12.0287(8) A, β = 99.303(2) ] is different from C2/c previously reported for Ca5Si2N6, while both polymorphs are composed of Ca2+ and edge-sharing double tetrahedra [Si2N 6]10-.

Investigation of hydrogen desorption from CaSiH by means of calorimetric method

The present work deals with the study of the reaction of hydrogen desorption from the CaSiHX hydride by means of the calorimetric method. The dehydrogenation of the CaSiHX hydride was carried out at 548 K. For a calorimetric study, the installation composed of the differential heat-conducting Tian-Calvet type calorimeter connected with a conventional Sieverts-type apparatus was employed. Such installation permitted us to obtain simultaneously the P-X isotherms (P - equilibrium hydrogen pressure, X = H/CaSi) and variation of the partial molar enthalpies of the reaction of hydrogen desorption from CaSiHX with the hydrogen concentration in the metallic matrix. It was ascertained that in the CaSi-H2 system there was one region where values of the partial molar enthalpy of the reaction of hydrogen desorption from the CaSiHX hydride remained constant. This means that formation of one hydride phase in the CaSi-H2 system took place. The enthalpy and entropy values for the reaction of hydrogen desorption from the CaSiHX in the plateau range are ΔH des = 53.8 ± 1.2 kJ mol-1 H2 and ΔS des = 94.2 ± 2.7 J mol-1 H2 K-1 (ΔH des and ΔS des - the differential molar enthalpy and entropy desorption, respectively).

Reversible hydriding and dehydriding properties of CaSi: Potential of metal silicides for hydrogen storage

The reversible hydriding and dehydriding properties of CaSi were investigated. First-principles calculations were performed to investigate the stability of CaSi hydride by the ultrasoft pseudo-potential method based on the density functional theory. A CaSi sample was examined by pressure-composition isotherm measurement, hydrogen analysis using the inert gas fusion method, and x-ray diffraction analysis. It was found that CaSi reversibly absorbs and desorbs hydrogen in a temperature range of 473-573 K. The reversible hydriding and dehydriding properties of CaSi indicate the potential of metal silicides for hydrogen storage.

Direct electrochemical preparation of nanostructured silicon carbide and its nitridation behavior

Silicon carbide was synthesized from mixtures of SiO2 and graphite by applying the concept of the FFC-Cambridge process and several fundamental aspects of the synthesis route were investigated. Porous disks composed of powders of SiO2 and graphite in molar ratios of 1:0.5, 1:1 and 1:1.5 were prepared by sintering in inert atmosphere and subjected to electro-deoxidation in molten CaCl2 at 1173 K under a range of experimental conditions. Disks of molar ratio 1:1.5, reduced at an applied voltage of 2.8 V for a duration of 6 h, yielded exclusively phase-pure SiC of nanowire morphology as the reaction product, while the other precursor compositions provided significant amounts of calcium silicides. Voltages lower than 2.8 V gave mixtures of SiC with elemental Si and graphite, and voltages higher than that gave CaSi alone. Shorter electro-deoxidation times led to incomplete reduction and allowed for the identification of CaSiO3 as a transient phase. Based on the experimental results a multipath reaction mechanism is proposed, consisting of the electrochemical reduction of SiO2 and CaSiO3 to Si and the subsequent in-situ carbonization of the Si formed to SiC. The effect of N2 at high temperature on the electrochemically synthesized SiC was investigated and the formation of nanowire Si2N2O was observed. Overall, the process presented is a facile single-step and low-temperature method for the synthesis of SiC with possible commercial prospects.

Phase selection during calcium silicide formation for layered and powder growth

Phase selection during Ca silicide formation was discussed using the chemical potential and the effective heat of formation (ΔH′) models. The compositional analyses of Ca silicides were experimentally carried out in detail for both the layered and powder

Effect of electrolysis potential on reduction of solid silicon dioxide in molten CaCl2

Electrochemical reduction of solid SiO2 by using a contacting electrode method was investigated in molten CaCl2 at 1123 K. The samples were prepared by potentiostatic electrolysis at 0.35-1.30 V (vs. Ca 2+/Ca) for 1 h. From the results of XRD, SEM and EPMA, it was confirmed that SiO2 was electrochemically reduced to Si at 1.25 V or more negative potential, which agreed with the thermodynamic calculation. The current-time curves during electrolysis and the cross-sectional SEM measurements of the samples clearly showed that reduction rate is higher at more negative potential. In addition, Si-Ca alloy formation was confirmed at 0.35 V.