Research on near infrared photoelectric response and surface-enhanced Raman scatteringof urchin-like Au-Ag-Pt-Pd nanoalloy

Hui Ma,Yue Tian,An-Xin Jiao,Chang Wang,Ming Chen,School Of Physics, Shandong University, Jinan 250100, China ,Meng-Ya Zhang

doi:10.7498/aps.71.20212094

Abstract

Compared with the single metal, multi-metallic nanoparticle has excellent localized surface plasmon resonance with a wide spectral range response, which is beneficial to improving both the photoinduced electron transfer efficiency and the effective electron-hole separation. In this work, the urchin-like Au-Ag-Pt-Pd nanoalloy (Au-Ag-Pt-Pd NU) with multiple tentacles is successfully synthesized by the seed growth method and chemical reduction method. And we explore the optical properties of Au-Ag-Pt-Pd NU at different annealing temperatures. The results show that the transient photocurrent intensity of Au-Ag-Pt-Pd NU annealed at 200 ℃ is 1.6 times that of the primitive Au-Ag-Pt-Pd NUs at 808 nm excitation. In addition, the SERS signal intensity of crystal violet (CV) adsorbed on the Au-Ag-Pt-Pd NUs annealed at 200 ℃ is 1.8 times that of the primitive Au-Ag-Pt-Pd NUs at 785 nm excitation. For the Au-Ag-Pt-Pd NUs in this work, the concentration of CV can be detected to be as low as 10–12 M. Furthermore, the interesting NIR-SERS sensor enables the detection limit of H2O2 at low concentration to reach 0.09–1.02 μmol/L. The results show that the obtained nanoalloy has excellent photoelectric response characteristics and high SERS sensitivity due to the synergistic effect of multi-metal. Thus, it possesses great potential for biological NIR detection in the future.

Highlights

与单金属相比,多金属纳米材料具有优异宽波谱范围响应的局部表面等离子体共振(LSPR),有利于提高光致电子转移效率并促进电荷载流子的有效分离.本文通过种子生长法和化学还原法,成功合成了具有多触角的海胆状金/银/铂/钯(Au-Ag-Pt-Pd NUs)四元纳米合金,探究了该纳米合金在不同退火温度下的 LSPR 响应特性,实验结果显示,在近红外光 (808 nm)激发下,退火 200°C的 Au-Ag-Pt-Pd NUs 的瞬态光电流强度是初始 Au-Ag-Pt-Pd NUs 的 1.6 倍. 此外,以结晶紫(CV)作为探针分子,退火 200°C的 Au-Ag-Pt-Pd NUs 的表面增强拉曼光谱(SERS)信号强度是初始 Au-Ag-Pt-Pd NUs 的 1.8 倍,从而验证了退火 200°C的 Au-Ag-Pt-Pd NUs 具有很好的 SERS 活性,同时 CV 探测浓度可低至 10-12 M,并且实现了低浓度 H2O2 探测,探测范围:0.09-1.02μmol/L. 结果表明,由于多重金属协同效应,四元 Au-Ag-Pt-Pd NUs 复合结构具备优异的光电响应特性和较高的 SERS 灵敏度,可为贵金属生物近红外探测提供新的思路
peak histogram of CV absorbed on Au-Ag-Pt-Pd NUs
最后 , 基于退火 200 °C 的 Au-Ag-Pt-Pd NUs 基底进行了 SERS 性能测试,实现了 CV 浓度从 10-7-10-12 M 的探测,并且实现了低浓度 H2O2 探测,范围:0.09-1.02 μmol/L.结果表明,具有优异光电响应的四金属 Au-Ag-Pt-Pd NUs 的多重协同效果将为贵金属近红外生物探测提供新的思路

Summary

Introduction

与单金属相比,多金属纳米材料具有优异宽波谱范围响应的局部表面等离子体共振(LSPR),有利于提高光致电子转移效率并促进电荷载流子的有效分离.本文通过种子生长法和化学还原法,成功合成了具有多触角的海胆状金/银/铂/钯(Au-Ag-Pt-Pd NUs)四元纳米合金,探究了该纳米合金在不同退火温度下的 LSPR 响应特性,实验结果显示,在近红外光 (808 nm)激发下,退火 200°C的 Au-Ag-Pt-Pd NUs 的瞬态光电流强度是初始 Au-Ag-Pt-Pd NUs 的 1.6 倍. 此外,以结晶紫(CV)作为探针分子,退火 200°C的 Au-Ag-Pt-Pd NUs 的表面增强拉曼光谱(SERS)信号强度是初始 Au-Ag-Pt-Pd NUs 的 1.8 倍,从而验证了退火 200°C的 Au-Ag-Pt-Pd NUs 具有很好的 SERS 活性,同时 CV 探测浓度可低至 10-12 M,并且实现了低浓度 H2O2 探测,探测范围:0.09-1.02μmol/L. 结果表明,由于多重金属协同效应,四元 Au-Ag-Pt-Pd NUs 复合结构具备优异的光电响应特性和较高的 SERS 灵敏度,可为贵金属生物近红外探测提供新的思路. 与单金属相比,多金属纳米材料具有优异宽波谱范围响应的局部表面等离子体共振(LSPR),有利于提高光致电子转移效率并促进电荷载流子的有效分离.本文通过种子生长法和化学还原法,成功合成了具有多触角的海胆状金/银/铂/钯(Au-Ag-Pt-Pd NUs)四元纳米合金,探究了该纳米合金在不同退火温度下的 LSPR 响应特性,实验结果显示,在近红外光 (808 nm)激发下,退火 200°C的 Au-Ag-Pt-Pd NUs 的瞬态光电流强度是初始 Au-Ag-Pt-Pd NUs 的 1.6 倍. 结果表明,由于多重金属协同效应,四元 Au-Ag-Pt-Pd NUs 复合结构具备优异的光电响应特性和较高的 SERS 灵敏度,可为贵金属生物近红外探测提供新的思路.

Results

Conclusion