Synthesis of Bi–Fe–Sb–O Pyrochlore Nanoparticles with Visible‐Light Photocatalytic Activity

Abstract

A method has been developed for the preparation of Bi-Fe-Sb-O pyrochlore nanoparticles by microwave hydrothermal treatment. Experiments revealed that the preparation procedure for the precursors is an important factor that affects the phase composition of the product. The morphology of the pyrochlore particles was investigated by SEM, HRTEM, and se-

Pyrochlore phase in the Bi2O3-Fe2O3-WO3-(H2O) system: its stability field in the low-temperature region of the phase diagram and thermal stability

“…The pyrochlore-structured complex oxide compounds attract the researchers active attention because they have a set of interesting physicochemical properties for investigation, in particular, magnetic [1][2][3][4][5], dielectric [3,[5][6][7], transport [8,9], photocatalytic [10][11][12]. Due to this, they can be considered as promising materials for the manufacture of coatings, for example, parts of gas turbines operating at elevated temperatures [13], as well as ion-exchange materials for the immobilization of radioactive waste [14].…”

“…Due to this, they can be considered as promising materials for the manufacture of coatings, for example, parts of gas turbines operating at elevated temperatures [13], as well as ion-exchange materials for the immobilization of radioactive waste [14]. The pyrochlore-structured compounds are characterized by a large isomorphic capacity, which determines the existence of this structural type in both binary [14][15][16] and more multicomponent oxide systems [1][2][3][4][5][6][7][8][9][10][11]. In most oxide systems, the pyrochlore-structured compounds are obtained from simple oxides by the solid-state synthesis, since, as a rule, this structural type is quite stable at elevated temperatures [17,18].…”

“…In most oxide systems, the pyrochlore-structured compounds are obtained from simple oxides by the solid-state synthesis, since, as a rule, this structural type is quite stable at elevated temperatures [17,18]. Despite this, the application of "soft chemistry" methods, in particular, the hydrothermal method, opens up opportunities for studying phase transformations involving the pyrochlore phase, occurring in the low-temperature region of phase diagrams [19][20][21][22][23]. It should be noted that, as a rule, complex oxide phases of variable composition are characterized by a narrowing of the equilibrium concentration boundaries of the stability field with increasing synthesis temperature, that is, when moving towards the melting or solid-phase decomposition temperature.…”

The effect of rare earth (Er, Yb) element doping on the crystallization of Y2Ti2O7 pyrochlore nanoparticles developed by hydrothermal-assisted-sol-gel method

“…Pyrochlore is an interesting model material have a wide range of functional properties leading to a many areas of engineering and technology [1][2][3][4] in optical field [5,6]. These materials can exhibit piezo-electric, magnetic, catalytic [7][8][9] and electrooptical properties; they possess ionic conductivity, low thermal conductivity, high melting point, optical nonlinearity, low photonic cut off energy [10] and good chemical and mechanical stability [11][12][13][14][15][16]. Thus, they are known as superconductors, photocatalysts, multiferroics, and dielectrics [17,18,[18][19][20].…”

“…In particular, Yb 3+ /Er 3+ co-doped nanomaterials have good performance in terms of red and green UC emissions [48][49][50] and can enhance the luminescence efficiency. Er 3+ and/or Yb 3+ doped Y2Ti2O7 materials have been widely studied as nanoparticles [36,44], ceramics [51], photonic crystals [7,52], glass-ceramic [53] and bulk [13], all of these samples exhibit yellow-green emissions with low doping concentration, and most of the studies are focus on using 980 nm as the excitation source. The Y2Ti2O7 pyrochlore is one of the excellent dynamic host for RE ions (Er 3+ , Ho 3+ , Tm 3+ , Dy 3+ , etc.)…”