The enhancement of the surface-enhanced Raman scattering (SERS) property of the plasmonic metal oxide semiconductor nanostructures by controlling their phase, shape, size, and oxygen vacancy to detect trace amounts of organics is of significant interest. In this study, a simple surfactant-free hydrothermal strategy was proposed to fabricate crystalline h-MoO_3–x and α-MoO_3–x nanomaterials with tunable plasmonic properties. Herein, the crystal phase, morphology, and oxygen vacancy of MoO_3–x nanostructures were precisely controlled under suitable synthetic conditions. The plasmonic properties of the as-synthesized h-MoO_3–x and α-MoO_3–x micro-/nanostructures were controlled by adjusting the residual volume in the autoclaving chamber. In addition, the plasmonic MoO_3–x exhibited SERS activity with a detection limit as low as 1.0 × 10^–9 M and the maximum enhancement factor (EF) up to 6.99 × 10⁵ for h-MoO_3–x, while for α-MoO_3–x, the detection limit was 1.0 × 10^–7 M with the corresponding EF up to 8.51 × 10³, comparable with plasmonic noble metal nanomaterials without a “hot spot”.

中文翻译：

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相和形态控制的可调谐等离子体MoO _{3– x}纳米材料的合成，用于超灵敏表面增强拉曼光谱检测

通过控制其相，形状，大小和氧空位以检测痕量有机物，提高等离子体金属氧化物半导体纳米结构的表面增强拉曼散射（SERS）特性是非常重要的。在这项研究中，一个简单的无表面活性剂的水热策略提出了制造结晶H-的MoO _{3- X}和α-的MoO _{3- X}纳米材料具有可调电浆性质。在这里，在合适的合成条件下，可以精确地控制MoO _{3– x}纳米结构的晶相，形态和氧空位。所合成的H-的MoO的等离激元属性_{3- X}和α-的MoO _{3- X}通过调节高压灭菌室中的残留体积来控制微/纳米结构。此外，等离子MoO _{3– x}表现出SERS活性，h-MoO ₃ – _x的检出限低至1.0×10 ^–9 M，最大增强因子（EF）高达6.99×10 ⁵，而α为-MoO _{3– x}，检出限为1.0×10 ^–7 M，相应的EF高达8.51×10 ³，与没有“热点”的等离激元贵金属纳米材料相当。