Surface-Functionalized Au–Pd Nanorods with Enhanced Photothermal Conversion and Catalytic Performance

作者：Yuhang Zhao, Radwan M. Sarhan, Alberto Eljarrat, Zdravko Kochovski, Christoph Koch, Bernd Schmidt, Wouter Koopman, Yan Lü · 发表于：ACS Applied Materials & Interfaces · 年份：2022 · DOI：10.1021/acsami.2c00221 · 被引用次数：37 · 研究领域：Gold and Silver Nanoparticles Synthesis and Applications、Copper-based nanomaterials and applications、Nanomaterials for catalytic reactions

Bimetallic nanostructures comprising plasmonic and catalytic components have recently emerged as a promising approach to generate a new type of photo-enhanced nanoreactors. Most designs however concentrate on plasmon-induced charge separation, leaving photo-generated heat as a side product. This work presents a photoreactor based on Au–Pd nanorods with an optimized photothermal conversion, which aims to effectively utilize the photo-generated heat to increase the rate of Pd-catalyzed reactions. Dumbbell-shaped Au nanorods were fabricated via a seed-mediated growth method using binary surfactants. Pd clusters were selectively grown at the tips of the Au nanorods, using the zeta potential as a new synthetic parameter to indicate the surfactant remaining on the nanorod surface. The photothermal conversion of the Au–Pd nanorods was improved with a thin layer of polydopamine (PDA) or TiO 2 . As a result, a 60% higher temperature increment of the dispersion compared to that for bare Au rods at the same light intensity and particle density could be achieved. The catalytic performance of the coated particles was then tested using the reduction of 4-nitrophenol as the model reaction. Under light, the PDA-coated Au–Pd nanorods exhibited an improved catalytic activity, increasing the reaction rate by a factor 3. An analysis of the activation energy confirmed the photoheating effect to be the dominant mechanism accelerating the reaction. Thus, the increased photothermal heating is respon...