An oxalate complex of vanadyl(iv) (Bu4N)(2)[VO(C2O4)(2)] (I) was synthesized and used as a vanadium precursor. The synthesis and characterization of the double complex salts [Pt(NH3)(4)][VO(H2O)(C2O4)(2)]2H(2)O (III) and {[Pt(NH3)(4)][VO(C2O4)(2)]}(n) (IV) were carried out. The complexes obtained were characterized by IR and diffuse reflectance spectroscopy, single-crystal and powder X-ray diffraction, and EPR. The magnetic properties of I, III, and IV were also studied. The process of thermal decomposition of the synthesized complexes in reducing and inert atmospheres was studied, and the composition of the released gases was determined. Thermal decomposition of the salts in a hydrogen atmosphere at 600 degrees C resulted in the formation of a bimetallic solid solution, Pt0.6V0.4.

Heteronuclear coordination compounds of d-metals are suitable single-source precursors for bimetallic nanoalloys, which often show extraordinary catalytic properties due to synergetic effect. In particular, Ni- and Rh-based catalysts are highly effective in low temperature steam reforming processes. Double oxalates of Rh with Ni and Co of the formula {[Rh(H2O)(2)(C2O4)mu-(C2O4)](2)M(H2O)(2)}center dot 6H(2)O (M = Ni, Co) were synthesized and structurally characterized. According to thermogravimetric analysis, the complexes decompose completely in He and H-2 atmospheres to form corresponding nanoalloys at similar to 300 degrees C. The calcination in O-2 atmosphere leads to formation of spinel type mixed oxide. The supported Co-Rh/Al2O3 and Ni-Rh/Al2O3 catalysts were prepared by impregnation of double oxalate complexes in porous support with subsequent calcination and tested in propane low temperature steam reforming in CH4 excess. The Co-containing catalyst showed comparable activity regarding to pure Rh/Al2O3 sample, while bimetallic Ni-Rh/Al2O3 catalyst revealed to be appreciably more active, than monometallic catalysts with higher active component loadings. Rh-Ni catalyst allowed for complete propane conversion at T approximate to 350 degrees C, whereas for Rh catalyst the temperature was T approximate to 410 degrees C, and Rh-Co did not reach complete C3H8 conversion at all. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Development of N-doped Pd/C catalysts for hydrogen production from gas-phase formic acid is a challenge. To elucidate the efficient routes of nitrogen insertion on the surface of a mesoporous carbon support, the latter was treated with melamine (Mel), dicyandiamide or NH3 at 673 and 823 K. Pyrolysis of the melamine/carbon mixture taken in a 1:2 ratio provides an increase in the reaction rate by a factor of 5. The inserted N-sites strongly interact with Pd leading to the formation of highly dispersed Pd nanoparticles (similar to 1.6 nm) and active atomically dispersed Pd2+ species. With a further increase of the Mel/C ratio, the number of surface N-sites decreases due to occupation of carbon support pores with a g-C3N4-type residue. This provides a decrease in the Pd dispersion leading to lower reaction rates. Therefore, melamine is an efficient N precursor. The considered synthesis of N-doped catalysts could be scaled. (c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Remarkable solvation-induced emission enhancement is discovered on a new Ag(i) complex showing sky-blue thermally activated delayed fluorescence (TADF).

The ammonium salt (NH4)(2)[RuNO(NO2)(4)OH] was prepared, characterized by thermogravimetric analysis, IR spectroscopy and its molecular and crystal structures were determined. Heating of the salt was investigated in organic solvents (pyridine and acetonitrile) using( 15)N-NMR spectroscopy and the reaction led to the preparation of the [RuNO(NO2)(3)(Py)OH](- )anion with good yield (60%). Crystal structures of the two products (NH4)[RuNO(NO2)(3)(Py)OH] and NH4[RuNO(NO2)(3)(NH3)OH] were determined. Both (NH4)(2)[RuNO(NO2)(4)OH] and (NH4)[RuNO(NO2)(3)(Py)OH] underwent photo-induced (445 nm) linkage isomerization (RueNO to Ru-ON) but the population of the metastable isomer did not exceed 5-7%. (C) 2018 Elsevier B.V. All rights reserved.

The reaction of trans-[Ru(NO)Py 2Cl 2(OH)] with concentrated o-phosphoric acid, after washing the mixture with diethyl ether, gave trans-[Ru(NO)Py 2Cl 2(H 2O)]H 2 PO 4 ⋅2H 3 PO 4 ⋅H 2O (I) in nearly quantitative yield. The structure of this compound was determined by X-ray diffraction analysis: space group P-1. Washing of I with ethanol afforded the dihydrophosphate salt trans-[Ru(NO)Py 2Cl 2(H 2O)]H 2 PO 4 ⋅H 2O (II) (yield 97%). The thermal decomposition of I and II in a helium atmosphere resulted in the formation of ruthenium phosphide RuP as a predominant component along with Ru 2P or RuP 2. Preliminary photoisomerization experiments for trans-[Ru(NO)Py 2Cl 2(OH)] and trans-[Ru(NO)Py 2Cl 2(H 2O)]H 2 PO 4 ⋅H 2O suggested the presence of metastable states. DSC experiments have been carried out for both compounds. The measured kinetic parameters for the metastable decay for trans-[Ru(NO)Py 2Cl 2(H 2O)]H 2 PO 4 ⋅H 2O were E a = 90.7 ± 2.4 kJ/mol, log 10(k 0/sec −1) = 18.9 ±0.6, and T d = 217 K.

The synthesis of Au nanoparticles through the reduction of HAuCl4 with sodium borohydride in a mixture of ethanol and isopropanol in the presence of tris(2-aminoethyl)amine is presented. The resulting powder preparation is a mixture of primary particles with the average diameter of golden cores 3.2 +/- 0.6 nm, and secondary particles that were formed as a result of agglomeration of the primary ones and have core diameter up to 20 nm. The Au content of the preparation is 1.94% because Au nanoparticles have voluminous protective shells composed of the adducts of tris(2-aminoethyl)amine, acetone and boric acid, formed due to hydrogen bonding. The preparation is hydrophilic and allows one to obtain colloid solutions in water and polar solvents like acetone, isopropanol, dimethylsulphoxide, and in chloroform under ultrasonic treatment. (C) 2013 Elsevier BM. All rights reserved.