Department of Chemistry and Center for Nanostructured Electronic Materials, University of Florida, Gainesville, FL 32611 (USA).
Angew Chem Int Ed Engl. 2014 Jul 21;53(30):7887-91. doi: 10.1002/anie.201404259. Epub 2014 Jun 11.
Ideal solar-to-fuel photocatalysts must effectively harvest sunlight to generate significant quantities of long-lived charge carriers necessary for chemical reactions. Here we demonstrate the merits of augmenting traditional photoelectrochemical cells with plasmonic nanoparticles to satisfy these daunting photocatalytic requirements. Electrochemical techniques were employed to elucidate the mechanics of plasmon-mediated electron transfer within Au/TiO2 heterostructures under visible-light (λ>515 nm) irradiation in solution. Significantly, we discovered that these transferred electrons displayed excited-state lifetimes two orders of magnitude longer than those of electrons photogenerated directly within TiO2 via UV excitation. These long-lived electrons further enable visible-light-driven H2 evolution from water, heralding a new photocatalytic paradigm for solar energy conversion.
理想的太阳能燃料光催化剂必须有效地利用太阳光，产生大量用于化学反应的长寿命电荷载流子。在这里，我们展示了在传统光电化学电池中加入等离子体纳米粒子的优点，以满足这些令人生畏的光催化要求。电化学技术被用来阐明在可见光（λ>515nm）照射下，金/二氧化钛异质结构中等离子体介导的电子转移的机理。值得注意的是，我们发现这些转移的电子的激发态寿命比通过紫外光激发直接在 TiO2 中产生的电子的寿命长两个数量级。这些长寿命的电子进一步实现了可见光驱动的水析氢，为太阳能转化开辟了一个新的光催化范例。
