Manganese–Zinc Ferrite Synthesis by the Sol–Gel Autocombustion Method. Effect of the Precursor on the Ferrite’s Catalytic Properties

Abstract

Manganese−zinc ferrites were obtained through combined coprecipitation and sol−gel autocombustion methods. The effect of the precursor used in the sol−gel autocombustion synthesis on the ferrite's structural and catalytic properties was examined. The ferrite powders were characterized by XRD, BET, SEM, TG/DTA, and TPR-H 2 , and their acidic−basic properties were determined using cyclohexanol and the TPD-NH 3 test. The ferrite powder obtained from the hydroxide precursor (SC1-OH) has a larger specific surface area (16.41 m 2 /g), a larger crystallite size (35.6 nm), and a more heterogonous structure, which make it a more active catalyst. This is also achieved because of the existence of both acidic and basic centers on its surface. The ferrite obtained from the oxalate precursor (SC2-C2O4) has smaller (29.6 nm) but more aggregated particles. As a catalyst, it is more selective to dehydrogenation, which is related to its higher reducibility. The SC2-C2O4 sample also exhibits higher selectivity to ketone, and it is a much more efficient catalyst at higher temperatures.

Synthesis and characterization of manganese–zinc ferrite obtained by thermal decomposition from organic precursors

“…Owing to their developed specific surface and high surface energy they can be used as catalysts [1][2][3] or gas sensors [4]. Nanoferrites with belowcritical grain size at room temperature are characterized by superparamagnetism, low Curie temperature, and high magnetic flux density.…”

Photodegradation of textile dye using magnetically recyclable heterogeneous spinel ferrites

“…01‐089‐1012, 00‐001‐1121, 01‐077‐0010 and 00‐003‐0875 for ZnFe 2 O 4 , CoFe 2 O 4 , CuFe 2 O 4 and NiFe 2 O 4 , respectively). Analysis of diffraction pattern indicated formation of single phase FCC structure and the average crystallite size of all the samples was calculated using the Debye Scherrer equation: …”

A review on MnZn ferrites: Synthesis, characterization and applications

“…In addition, this review critically analyses methods and discusses on the choice of synthesis method for use of MnZn in a given application. In brief methods such as sol-gel method [96][97][98][99][100][101], co-precipitation method [85,[102][103][104][105][106][107][108][109], conventional ceramic technique [110,111], hydrothermal method [112][113][114], citrate precursor method [115][116][117], solid state reaction method [118], auto-combustion method [119] and microemulsion method [120] for the synthesis of MnZn are discussed. Various advantages and disadvantages of the synthesis methods are shown in Table 1.…”