The Effect of the Precursor Solution’s Pretreatment on the Properties and Microstructure of the SCS Final Nanomaterials

Abstract

Nanostructured nickel-based catalysts were produced by solution combustion synthesis and it was found that their properties and structure depended on the pretreatment of the precursor solution. X-ray diffraction, N2 adsorption, and an infrared high-speed camera were used to follow the various synthesis steps and to characterize the obtained catalysts, while their catalytic activity was determined in the hydrogenation of maleic acid. It was determined that the amount of water used and the heating of the precursor solution under mild stirring up to 70 °C influenced the nickel nitrate–glycine–water complexes that were formed in the precursor solution in the form of dendrites. These play a key role in the solution combustion synthesis (SCS) reaction mechanism and in particular in the formation of nickel-based catalysts. Understanding the interrelationships between the processing parameters and the ensuing powder properties allowed an efficient optimization of the catalytic performance.

Effects of Precursor Concentration in Solvent and Nanomaterials Room Temperature Aging on the Growth Morphology and Surface Characteristics of Ni–NiO Nanocatalysts Produced by Dendrites Combustion during SCS

“…For the first time, room temperature aging of oxide nanomaterials was investigated, as room temperature aging is new phenomenon for catalysts. Due to the increasing attention of researchers toward SCS and other approaches to synthesizing nano-catalysts as well as other nanomaterials, this research will play a significant role in nanomaterial studies.The importance of this work combined with our previous studies [19,21,40,43,44] is high, as it demonstrates that the severe control of the reaction conditions (such as the concentration of precursors in the solvent, the type of solvent, the solvent pretreatment conditions, preheating temperature, reagents concentration, etc.) provides the possibility of tuning the properties and characteristics of materials produced by SCS even at a large scale.…”

Direct Reduction in Greenhouse Gases by Continuous Dry (CO2) Reforming of Methane over Ni-Containing SHS Catalysts

“…Unique materials were developed by controlled high-temperature combustion as a result of synthesis by SHS [24]. The SHS method offers a unique method for the preparation of modern, highly active ceramic catalysts, as well as carriers with controlled composition and properties which satisfy the special requirements of various types of reactions [25][26][27][28][29][30][31][32][33][34][35][36][37]. The combustion temperature can reach up to 3000 • C (depending on the composition of the system) due to the exothermic reactions that occur within just a few minutes after the start of SHS synthesis.…”

Ni-Al-Mg-Mn COMPOSITE CATALYSTS FOR PARTIAL OXIDATION OF NATURAL GAS

“…For the above processes, oxide catalysts [1], their mixtures, and composites based on them [2] have been recently used instead of the noble metals [3,4] that were used previously. The method of self-propagating high-temperature synthesis has become widespread in recent years [5], especially its modification -the solution combustion synthesis (SCS) [6][7][8], as a result of which finely dispersed oxides and spinels are synthesized [9,10].…”