Plasmonic metal nanostructures can improve the photon-charge conversion efficiency in metal/semiconductor hybrid systems through direct electron transfer (DET), resonance energy transfer (RET), and accelerated exciton separation. These enhancement mechanisms of photon-charge conversion have been independently investigated, and it remains unclear which is the most efficient process for the conversion. Herein, DET is proposed as the most efficient pathway due to its ability to facilitate charge separation along with the extended band bending at the interface between the metal and the semiconductor under light irradiation. This investigation on plasmon-induced charge separation was carried out with metal-nanoparticle-decorated p-type semiconductor nanowires by wavelength-tunable light-irradiated Kelvin probe force microscopy and photocurrent measurements. In addition, the band alignment between the metal and the semiconductor was characterized by density functional theory calculations. DET was shown to be superior to RET by an approximated ratio of 8:2 with the coexistence of both plasmonic and excitonic excitations. This observation suggests a straightforward way to develop efficient photocatalysts – engineering individual pathways of plasmon-induced charge separation and transfer.

等离子体金属纳米结构可以通过直接电子转移（DET），共振能量转移（RET）和加速激子分离来提高金属/半导体混合系统中的光子电荷转换效率。光子电荷转换的这些增强机制已得到独立研究，目前尚不清楚哪一个是最有效的转换过程。在本文中，DET被提议为最有效的途径，因为它具有促进电荷分离以及在光照射下金属与半导体之间的界面处的扩展带弯曲的能力。用金属-纳米粒子修饰的p对等离激元诱导的电荷分离进行了研究型半导体纳米线通过波长可调光照射的开尔文探针力显微镜和光电流测量。另外，通过密度泛函理论计算来表征金属与半导体之间的能带对准。已证明，DET以8：2的近似比率优于RET，并同时存在等离激元和激子激发。该观察结果提出了开发高效光催化剂的直接方法-设计等离激元诱导的电荷分离和转移的单个途径。