Plasmonic semiconductor nanoparticles (NPs) with wide-range tailorable localized surface plasmon resonance (LSPR) hold exciting prospects on optical signal amplification. In this work, by precisely controlling oxygen vacancies around W atoms, plasmonic bismuth tungstate Bi₂WO₆ (BWO) nanosheets are constructed to enhance emission of Yb³⁺/Er³⁺ co-doped NaYF₄ upconversion nanoparticles (UCNPs). In the optimal conditions, the UCNPs/BWO-2 hybrids exhibit over three-order (1260-fold) enhancement selectively on the 520 nm emission owing to the strong LSPR-induced electrical field and photothermal effect. Moreover, it is found that the highly efficient emission of UCNPs/BWO-2 allows it to act as a thermometer to monitor the real-time local temperature with high absolute sensitivity of 5.8 × 10⁻³ K⁻¹ in wide temperature range (up to 990 K). For proof-of-concept, the dual functions of plasmonic UCNPs/BWO-2 hybrids on bioimaging and photothermal therapy for cancer cells are demonstrated that can be completely killed within 5 min under 980 nm irradiation. As far as it is known, this work reaches a new level on UCNPs emission enhancement by plasmonic semiconductor, exceeding most plasmonic metals.

中文翻译：

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具有三阶增强上转换发射和光热生物疗法的双功能非金属等离子体杂化物

具有大范围可定制局部表面等离子体共振 (LSPR) 的等离子体半导体纳米粒子 (NP) 在光信号放大方面具有令人兴奋的前景。在这项工作中，通过精确控制 W 原子周围的氧空位，构建等离子体钨酸铋 Bi ₂ WO ₆ (BWO) 纳米片以增强 Yb ³⁺ /Er ³⁺共掺杂 NaYF _4的发射上转换纳米粒子 (UCNP)。在最佳条件下，由于强局域表面等离子体共振诱导的电场和光热效应，UCNPs/BWO-2 杂化物在 520 nm 发射选择性地表现出超过三阶（1260 倍）的增强。^{此外，还发现 UCNPs/BWO-2 的高效发射使其可以充当温度计，以 5.8 × 10 −3}  K ⁻¹的高绝对灵敏度监测实时局部温度在宽温度范围内（高达 990 K）。对于概念验证，等离子体 UCNPs/BWO-2 混合体在癌细胞的生物成像和光热疗法方面的双重功能被证明可以在 980 nm 照射下 5 分钟内完全杀死。据了解，这项工作在等离子体半导体增强 UCNPs 发射方面达到了一个新的水平，超过了大多数等离子体金属。