Abstract:
The interaction of graphene with metals initiates charge-transfer interaction-induced chemical enhancements, which critically depend on the doping effect from deposited metallic configurations. In this paper, we have explored the gold nanoparticle-decorated monolayer graphene nanosheets for the large graphene-induced Raman enhancement of adsorbed analytes, indicating the surface-enhanced Raman spectroscopy (SERS) capabilities of metal-doped graphene (G-SERS). Here, the systematically sputtered Au thickness optimization procedure revealed noticeable modifications in the graphene Raman spectra and photoluminescence (PL) background quenching, which indicated favorable charge transfer through n-type doping of chemical vapor deposition-grown graphene nanosheets. The highly consistent, individually distributed morphology of the gold nanoislands over graphene nanosheets depicted a reproducibly uniform G-SERS signal with excellent relative standard deviation values (<5%), resulting in the strongest Raman intensity enhancement factors of ∼108 (MB) (methylene blue) and 107 (DPA) (2,6-pyridinedicarboxylic acid) composed of the weakest PL background. The combined charge-transfer-induced chemical enhancement and electromagnetic enhancement from individual Au nanoislands result in a lowering of detectability down to 10-16 M (MB) and 10-11 M (DPA) concentrations with efficient time-dependent signal stability. Additionally, the GAu demonstrated its effective (∼94.4%) photocatalytic degradation capabilities by decomposing MB dye molecules from a concentration of 1 μM to 2.52 fM within 60 min. Therefore, the prominent charge-transfer contribution through controlled Au decoration over graphene nanosheets provides a potential strategy for fabricating superior SERS sensors and photocatalysts exhibiting adequate signal consistency, stability, and photodegradation efficiency through overcoming the limitations of the traditional sensing platforms.
摘要:
石墨烯与金属的相互作用引发电荷转移相互作用诱导的化学增强,这主要取决于沉积金属构型的掺杂效应。在本文中,我们已经探索了金纳米粒子修饰的单层石墨烯纳米片,用于吸附分析物的大型石墨烯诱导的拉曼增强,表明金属掺杂石墨烯(G-SERS)的表面增强拉曼光谱(SERS)能力。这里,系统地溅射Au厚度优化程序揭示了石墨烯拉曼光谱和光致发光(PL)背景猝灭的显着变化,这表明通过化学气相沉积生长的石墨烯纳米片的n型掺杂的良好的电荷转移。高度一致,石墨烯纳米片上的金纳米岛的单独分布形态描绘了具有优异的相对标准偏差值(<5%)的可重复均匀的G-SERS信号。导致最强的拉曼强度增强因子~108(MB)(亚甲基蓝)和107(DPA)(2,6-吡啶二羧酸)组成最弱的PL背景。来自各个Au纳米岛的组合的电荷转移诱导的化学增强和电磁增强导致可检测性降低至10-16M(MB)和10-11M(DPA)浓度,具有有效的时间依赖性信号稳定性。此外,GAu通过在60分钟内将MB染料分子从1μM的浓度分解为2.52fM,证明了其有效的(〜94.4%)光催化降解能力。因此,通过石墨烯纳米片上的受控Au装饰,突出的电荷转移贡献为制造具有足够信号一致性的卓越SERS传感器和光催化剂提供了潜在的策略,稳定性,和光降解效率,通过克服传统传感平台的局限性。