利用發光銅奈米團簇偵測硫化氫

Abstract

本篇論文主要是利用硫醇分子青黴胺（penicillamine）與銅離子合成發光銅奈米團簇聚集體（copper nanocluster aggregates），並用於偵測水溶液中的硫化氫（hydrogen sulfide）濃度。銅奈米團簇聚集體具有溶劑影響放光、長斯托克斯位移（Stokes shift，254 nm）、長放光生命期（τ1和τ2分別為0.4 ns (3%)和126.5 ns (97%)）以及高量子產率（quantum yields，QY = 2.0%）等光學性質，適合應用在環境樣品的分析。發光的銅奈米團簇聚集體會與硫化氫反應生成顆粒較大且不具放光性質的硫化銅奈米粒子（copper sulfide nanoparticles），透過分析物誘導放光消光作用（analyte-induced photoluminescence quenching）使得銅奈米團簇聚集體的放光變弱。在最佳化的反應條件下（pH值為4.0，常溫下避光反應40分鐘），硫化氫的偵測極限（limit of detection）為500 nM，其線性範圍為1–100 μM，與環境中其它干擾離子相比，銅奈米團簇聚集體對於硫化氫具有較高的選擇性（大於10倍），因此可應用在溫泉水樣品中硫化氫濃度測定，並且具有製備簡單、成本低、快速偵測且精準的優點。

In this study, we unveiled a novel copper nanocluster (Cu NCs)-based sensor for the determination of hydrogen sulfide (H2S) in hot spring waters with high selectivity and sensitivity. We have developed a one-pot, inexpensive, simple and rapid method to synthesize photoluminescent Cu NC aggregates from Cu2+ ions in 65% (v/v) dimethylformamide (DMF) aqueous solution containing penicillamine (PA) as a capping and reducing agent. As-prepared PA-Cu NC aggregates emit at 580 nm when excited at 326 nm through an aggregation-induced emission effect, with solvent-dependent properties, a quantum yield of 2.0%, a long lifetime (τ1 = 0.4 ns (3%), τ2 = 126.5 ns (97%)), and a large stokes shift (254 nm). The PA-Cu NC aggregates are highly selective and sensitive for the detection of H2S, based on analyte-induced photoluminescence (PL) quenching through formation of CuS nanoparticles (NPs). The probe allows the detection of H2S, with a linear range of 1–100 μM and a limit of detection (LOD, signal-to-noise ratio = 3) of 500 nM. The practicality of this probe has been validated through the analysis of hot spring water samples.