Evaluation of two processing routes for the synthesis of molybdenum oxide with cobalt addition

Abstract

Molybdenum oxides are very interesting technologic materials, which present several industrial uses. The addition of a second metal may enhance its catalytic properties as well as change electronic behavior. Several methodologies for adding a second metal can be found in the literature, however, the comparison between them is hardly ever found. Here two processing routes were tested for the synthesis of molybdenum oxide with cobalt addition: solid-state and wet routes. Ammonium molybdate and cobalt nitrate were used as starting materials and cobalt addition was carried out before calcination. Starting materials were characterized by SEM, FTIR, XRF, and XRD. Calcination products were evaluated by SEM, XRF, XRD and UV-vis spectroscopy. Calcined products whose doping was performed via solid-state presented smaller crystal size (~25 nm), larger cobalt retention (deviation, δ ~10%) and slightly smaller band gap in comparison to those doped via the wet route (~40 nm and δ>11%).

Magnetically Doped Molybdenum Disulfide Layers for Enhanced Carbon Dioxide Capture

“…Such a trend is reflected in the powder X-ray diffraction (PXRD) patterns, as illustrated in Figure b. The PXRD for MoS 2 shows major diffraction peaks at 2θ = 14, 33, and 57°, which could be assigned to reflection planes (002), (100), and (110), respectively. , The peaks at 17 and 26° could be attributed due to the leftover ammonium molybdate in the catalyst sample. , The presence of dopants leads to further loss in the crystallinity of the samples with the broadening of peaks. Such broadening is found to be less pronounced for the Ni-doped samples compared to those of the Fe- and Co-doped ones.…”

“…54,55 The peaks at 17 and 26°could be attributed due to the leftover ammonium molybdate in the catalyst sample. 56,57 The presence of dopants leads to further loss in the crystallinity of the samples with the broadening of peaks. Such broadening is found to be less pronounced for the Ni-doped samples compared to those of the Fe-and Co-doped ones.…”

Preparation and Characterization of FTO/nZnO/CH3NH3PbI3/C/Cu Perovskites Solar Cell

“…As shown in Table 3, the prepared PbI2 sample shows that the highly intensive line is oriented in the plane (1 0 6) instead of the plane (0 1 3) which may attribute to the preparation history and conditions. The particle size and strain were calculated from the Williamson-Hall formula [25,26] and Scherrer's equation [11,12,27].…”