Fast and safe synthesis of micron germanium in an ammonia atmosphere using Mo(2)N as catalyst

Here, we reported a new method for fast and safe synthesis of a micron germanium (Ge) semiconductor. The Ge was successfully prepared from mixed GeO(2) with a low amount of MoO(3) by the NH(3) reduction method at 800 °C for an ultra-short time of 10 min. XRD patterns show that the Ge has a tetragonal structure. SEM images show that the size of the Ge particles is from 5 μm to 10 μm, and so it is on the micron scale. UV-visible diffuse reflectance spectroscopy shows that the Ge has good light absorption both in the ultraviolet and visible regions. The formation of Ge mainly goes through a two-step conversion in the NH(3) flow. Firstly, GeO(2) is converted to Ge(3)N(4), and then Ge(3)N(4) is decomposed to generate Ge. The comparison experiments of MoO(3) and Mo(2)N demonstrate that Mo(2)N is the catalyst for the Ge synthesis which improves the Ge(3)N(4) decomposition. The presented fast and safe synthesis method of Ge has great potential for industrialization and the proposed Mo(2)N boosting the Ge(3)N(4) decomposition has provided significant guidance for other nitride decomposition systems.