Molybdenum oxide is an attractive material for application in several technology fields such as sensors, displays, and batteries, among many others. In this work, we present a reliable laser direct writing (LDW) method for synthesizing multi-phase molybdenum oxide (MoO_x) on a single processing step. We use femtosecond laser pulses to produce up to five distinct crystalline phases of molybdenum oxide at once. We demonstrate how the laser irradiation conditions determine the MoO_x stoichiometry, phase, and morphology. We show that by conveniently adjusting either the per-pulse laser fluence or the exposure time, MoO_x can be obtained in nano or micro-structured form. We found that this ultrashort pulse laser processing method allows for the formation of unusual MoO_x phases such as o-Mo₁₈O₅₂, which is rarely reported in the literature. In addition, it is possible to synthesize other sub-stoichiometric molybdenum oxide phases such as o-Mo₄O₁₁ and m-Mo₈O₂₃ all at atmospheric air conditions, with no need for demanding oxygen pressure precautions.

中文翻译：

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飞秒脉冲激光直接写入合成多相MoOx的快速生长

氧化钼是一种有吸引力的材料，可用于多种技术领域，例如传感器，显示器和电池等。在这项工作中，我们提出了一种可靠的激光直接写入（LDW）方法，可在单个处理步骤上合成多相氧化钼（MoO _x）。我们使用飞秒激光脉冲一次产生多达五个不同的氧化钼晶相。我们演示了激光照射条件如何确定MoO _x的化学计量，相位和形态。我们表明，通过方便地调整每脉冲激光能量密度或曝光时间，MoO _x可以以纳米或微结构形式获得。我们发现，这种超短脉冲激光加工方法允许形成异常的MoO _x相，例如o -Mo ₁₈ O ₅₂，这在文献中很少报道。此外，可以在大气条件下合成其他亚化学计量的氧化钼相，例如o -Mo ₄ O ₁₁和m -Mo ₈ O ₂₃，而无需严格的氧气压力预防措施。