Zhu Shilei, Deng Dan, Nguyen Mai Thanh, Chau Yuen-Ting Rachel, Wen Cheng-Yen, Yonezawa Tetsu
Division of Materials Science and Engineering, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
Department of Materials Science and Engineering, Center of Atomic Initiative for New Materials, National Taiwan University, No. 1, Section 4, Roosevelt Rd., Da'an District, Taipei, 10617, Taiwan.
Langmuir. 2020 Apr 7;36(13):3386-3392. doi: 10.1021/acs.langmuir.0c00382. Epub 2020 Mar 25.
Metal@semiconductor core-shell nanoparticles (NPs) are widely used in photocatalysts, sensors, and optical applications owing to their unique metal-semiconductor interface and the integration of the properties from both core and shell materials. Although many efforts have been made toward the precise synthesis of Au@CuO core-shell structures, the chemical stability of Au@CuO aqueous suspensions, which is of great significance in many related applications, is not mentioned in any published research. Herein we report the synthesis of Au@CuO core-shell NPs with small shell thickness from 2 to 40 nm through a wet-chemistry method. The UV-vis absorption properties are found to be tunable with CuO thickness in the range of 2-40 nm. Furthermore, the chemical stability of Au@CuO core-shell nanoparticle suspensions in water/ethanol mixed solvents is investigated. It is found that water/ethanol mixed solvents with a larger amount of water are more likely to deteriorate the stability of Au@CuO NPs by oxidizing CuO to CuO. The results from this work may provide useful information for the preparation of metal@CuO water-based suspensions that are expected to be used for SERS, photocatalyst, or photothermal applications.
金属@半导体核壳纳米粒子（NPs）因其独特的金属-半导体界面以及核壳材料性能的整合，在光催化剂、传感器和光学应用中得到广泛应用。尽管在精确合成Au@CuO核壳结构方面已做出诸多努力，但Au@CuO水悬浮液的化学稳定性在许多相关应用中具有重要意义，然而在任何已发表的研究中均未提及。在此，我们报道了通过湿化学方法合成壳层厚度在2至40纳米之间的小壳层厚度的Au@CuO核壳纳米粒子。发现紫外-可见吸收特性可随2至40纳米范围内的CuO厚度进行调节。此外，还研究了Au@CuO核壳纳米粒子悬浮液在水/乙醇混合溶剂中的化学稳定性。结果发现，含水量较高的水/乙醇混合溶剂更有可能通过将CuO氧化为CuO来降低Au@CuO纳米粒子的稳定性。这项工作的结果可能为制备有望用于表面增强拉曼光谱（SERS）、光催化剂或光热应用的金属@CuO水基悬浮液提供有用信息。
