Controllable synthesis and formation mechanism of pure and Fe-doped h-MoO3 microrods under hydrothermal reaction conditions

作者：Li, Hong-Xiao; Wang, Lu^*; Du, Feng-Jiao

来源：CrystEngComm, 2023, 25(28): 4089-4099.

DOI：10.1039/d3ce00411b

• PHOTOCATALYTIC DEGRADATION
• VISIBLE-LIGHT
• METASTABLE H-MOO3
• METHYLENE-BLUE
• MOO3
• TEMPERATURE
• BETA-MOO3
• PHASE
• NANO

In the present work, pure and Fe-doped h-MoO3 microrods were successfully synthesized via the hydrothermal method using (NH4)(6)Mo7O24 & BULL;4H(2)O and concentrated HNO3 as the raw materials. Various technologies, such as XRD, FESEM-EDS, TEM, and SAED pattern, were adopted to characterize the resulting products. The result showed that the optimum conditions for the controllable synthesis of pure h-MoO3 microrods were 150 & DEG;C, 16 h, and with a solid-liquid ratio of 1 : 2. Due to the similar ionic radius of Fe3+ and Mo6+, it was discovered that adding a small amount of Fe dopant (1-5 mass%) would not lead to an obvious change in the lattice parameters; however, the particle size of the as-synthesized Fe-doped h-MoO3 would be increased gradually. Also, the photocatalytic performances of the Fe-doped h-MoO3 increased first and then decreased with increasing the amount of Fe dopant. NH4+ and OH- existing in the system played crucial roles on the formation of h-MoO3 microrods, likely by acting as structure-directing and stabilizing agents for h-MoO3 crystalline. In addition, it was found that the transformation process from h-MoO3 microrods to & alpha;-MoO3 nanofibers obeyed the dissolution-recrystallization mechanism.