School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, Shandong, P. R. China.
Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, USA.
Nanoscale. 2016 May 19;8(20):10774-82. doi: 10.1039/c6nr00933f.
Nanostructured ZnO exhibits high chemical stability and unique optical properties, representing a promising candidate among photocatalysts in the field of environmental remediation and solar energy conversion. However, ZnO only absorbs the UV light, which accounts for less than 5% of total solar irradiation, significantly limiting its applications. In this article, we report a facile and efficient approach to overcome the poor wettability between ZnO and Au by carefully modulating the surface charge density on Au nanoparticles (NPs), enabling rapid synthesis of Au@ZnO core-shell NPs at room temperature. The resulting Au@ZnO core-shell NPs exhibit a significantly enhanced plasmonic absorption in the visible range due to the Au NP cores. They also show a significantly improved photocatalytic performance in comparison with their single-component counterparts, i.e., the Au NPs and ZnO NPs. Moreover, the high catalytic activity of the as-synthesized Au@ZnO core-shell NPs can be maintained even after many cycles of photocatalytic reaction. Our results shed light on the fact that the Au@ZnO core-shell NPs represent a promising class of candidates for applications in plasmonics, surface-enhanced spectroscopy, light harvest devices, solar energy conversion, and degradation of organic pollutants.
纳米结构的 ZnO 具有高化学稳定性和独特的光学性质，是环境修复和太阳能转换领域光催化剂中很有前途的候选材料。然而，ZnO 只吸收紫外线，而紫外线仅占太阳总辐照的不到 5%，这极大地限制了其应用。在本文中，我们报告了一种简便有效的方法，通过仔细调节 Au 纳米颗粒（NPs）表面的电荷密度，克服了 ZnO 和 Au 之间较差的润湿性，从而在室温下快速合成了 Au@ZnO 核壳 NPs。由于 Au NP 核的存在，所得的 Au@ZnO 核壳 NPs 在可见光范围内表现出显著增强的等离子体吸收。与单一组分的 Au NPs 和 ZnO NPs 相比，它们还表现出显著提高的光催化性能。此外，即使经过多次光催化反应循环，所合成的 Au@ZnO 核壳 NPs 的高催化活性也能保持。我们的结果表明，Au@ZnO 核壳 NPs 有望成为等离子体学、表面增强光谱学、光收集器件、太阳能转换和有机污染物降解等领域的一类有前途的候选材料。
