Thermodynamic analysis of nanoparticle size effect on catalytic kinetics

Synthesis and microstructure of cobalt ferrite nanoparticles

“…The powders with x = 0.6 and x = 1 have comparable conversion rates excepted for high concentration of CH 4 for which the cobalt ferrite powder with x = 0.6 shows a slightly better conversion rate than for the powder with x = 1. shape. It is well known that the efficiency of the catalytic conversion increases with the amount of exposed surface, the nature of the exposed cation sites, and the number and type of defects at the surface [37][38][39]. A relationship between particle size and catalytic activity was recently evidenced in the case of CoFe 2 O 4 nanoparticles [40], thus for only one composition x = 1.…”

Magnetic, electric and thermal properties of cobalt ferrite nanoparticles

“…It is well known that the efficiency of a catalytic conversion increases with the amount of exposed surface, which is related to the size and the shape of the particles, with the nature of the exposed cation sites, and the number and type of defects at the surface [17,18]. In nanostructured magnetic materials, surface effects usually lead to increased magnetization or superparamagnetism [2].Electric properties are also linked to the particle size, to the cation distribution and to the occurrence of vacancies [19,20].…”

Size dependence on reduction kinetic of iron based Fischer–Tropsch catalyst

“…Thermodynamic analysis of the effect of the nanoparticle size on adsorption equilibrium, chemical kinetic and rates was initiated by Parmon [29] and developed by YuMurzin [30,31]. The key in thermodynamic analysis is description of influence of the nanosize on the chemical potential of the active phase (e.g., clusters supported on a carrier).…”

“…This relation were used for the explanation of structure activity dependence in homogeneous and heterogeneous catalysis. The adsorption rate constant for forward reaction thus can be reported as [29][30][31][32]:…”

“…Since the catalytic properties of the nanoparticles depend on the size, nanoparticles with different sizes are expected to have different catalytic activity and selectivity. The dynamic surface of nanoparticles also depends on the size: smaller nanoparticles have higher surface energy and thus more prone to surface reconstruction, which can lead to different catalytic dynamics for nanoparticles with different sizes [11][12][13][14][15][16][17][29][30][31][32].…”