Analysis of Ca-PZT powder obtained by the Pechini and partial oxalate methods

Abstract

Ca-Pb(Zr,Ti)O3 (Ca-PZT) powders were prepared by a combined method, Pechini technique for the intermediate ZrTiO4 (ZT) particles and oxalate route for the final powder. The intermediate and final products were characterized by X-ray diffraction and BET for phase identification and granulometric analysis, respectively. The surface area of ZT powder reduced remarkably from 70 to 7.4 m²/g when the calcining temperature increased from 600 to 800 °C. Incremental pore volume and average pore diameters of the powder calcined at 700 °C for 3 h were 0.026 cm³/g and 70 Å, respectively. Ca-PZT powder calcined at 800 ºC for 3 h, with agglomeration factor (AF) 2.8, showed no hysteresis in BET analysis, which indicate small agglomeration without micropores among particles. The powder calcined at 750 ºC for 3 h, however, exhibited small AF and high sinterability.

Oxygen Rich Titania: A Dopant Free, High Temperature Stable, and Visible‐Light Active Anatase Photocatalyst

“…For example, the thermally most stable oxygen rich composition (16 H 2 O 2 ‐TiO 2 ) calcined at 900 °C has a 78‐fold increases in surface area, a 5‐fold increase in pore diameter and the pore volume in comparison to the control sample calcined at the same temperature (Table S1). The increased pore dia­meter observed for both control and oxygen rich compositions on increasing the calcination temperature may be due to the formation of interstitial pores associated with excessive grain growth at high temperatures 57. Stronger Ti–O–Ti bonds associated with smaller crystallite sizes of oxygen rich titania may be the vital reasons behind these improved textural properties.…”

“…Nitrogen isotherms of both control and oxygen rich titania (Figure S7) showed type IV characteristics with H1 type (cylindrical shape) of hysteresis 57. However, with an increase of oxygen content, the steepness of the hysteresis loop increased and the end of the hysteresis loop shifted towards higher relative pressure ( P / P 0 ), which represent their superior textural properties.…”

Nanostructured Ti1-xSxO2-yNy Heterojunctions for Efficient Visible-Light-Induced Photocatalysis

“…Nitrogen adsorption isotherms of both control and S,Ncodoped heterojunctions have type IV isotherms with H1 type of hysteresis (Supporting Information, Figure S8). 60 However, an increased steepness and ending of the hysteresis loop at a high relative pressure (P/P 0 ) of 0.7 with an increase of thiourea concentration is a measure of the high order of mesoporosity for S,N-codoped heterojunctions. 61 Among the titania samples obtained at various calcination temperatures, S,N-codoped heterojunctions showed significantly higher surface area, pore size, and pore volume compared to the control sample (Table 2).…”

“…The calculated d -spacing values of 3.38, 2.23, 1.70, and 1.22 Å represent the anatase lattice planes with Miller indices (101), (105), (004), and (204), respectively. , Rutile lattice planes (110), (101), (111), and (220) were also identified from the corresponding d -spacing values of 2.90, 2.50, 2.10, and 1.59 Å. , The complex SAED ring pattern of S,N-codoped heterojunctions confirmed the existence of polycrystalline anatase and rutile nanoparticles oriented in a random manner. Nitrogen adsorption isotherms of both control and S,N-codoped heterojunctions have type IV isotherms with H1 type of hysteresis (Supporting Information, Figure S8) . However, an increased steepness and ending of the hysteresis loop at a high relative pressure ( P / P 0 ) of 0.7 with an increase of thiourea concentration is a measure of the high order of mesoporosity for S,N-codoped heterojunctions .…”

High temperature synthesis of interfacial functionalized carboxylate mesoporous TiO2 for effective adsorption of cationic dyes

“…The isotherms of both samples are type IV adsorption isotherms with hysteresis loops in the relative range of 0.4-1.0 (Fig. 6a), which is indicative of mesoporous structures [26]. The isotherm of pristine TiO 2 shows a H4-type hysteresis loop, which may arise from the presence of large mesopores connected to surrounding pores of much smaller size, whereas the isotherm of the modified TiO 2 displays a H3-type hysteresis loop, which indicates that mesopores have cylindrical pore geometries.…”