Related Experiment Video
Updated: Jun 5, 2026
03:33
Fabrication of polydimethylsiloxane (PDMS)-Based Flexible Surface-Enhanced Raman Scattering (SERS) Substrate for Ultrasensitive Detection
Published on: November 17, 2023
Framework Response-Activated SERS Sensing: A Guest-Induced "Gate-Opening" Strategy for Ultrasensitive Sub-Ppt
Jia-Wei Huang1, Shu Han1, Tian-Qing Zhang1
1Zhejiang Province Key Laboratory of Optoelectronic Metrology and Precision Instruments, College of Optical and Electronic Technology, China Jiliang University, Hangzhou, 310018, China.
ACS Sensors
|June 4, 2026
Summary
A novel gold-based core-shell sensor array efficiently detects trace formaldehyde (CH2O), a harmful indoor VOC. This breakthrough enables highly sensitive and selective real-time monitoring for improved public health and environmental safety.
Area of Science:
- Materials Science and Engineering
- Nanotechnology
- Environmental Chemistry
Background:
- Accurate *in situ* monitoring of trace formaldehyde (CH2O), a high-risk indoor volatile organic compound (VOC), is crucial for public health.
- Direct surface-enhanced Raman scattering (SERS) detection of CH2O is challenging due to its weak Raman scattering and low adsorption affinity on noble metals.
Purpose of the Study:
- To develop an efficient sensing strategy for trace formaldehyde detection.
- To elucidate the sensing mechanism for enhanced capture and signal amplification.
Main Methods:
- Fabrication of an ordered Au@ZIF-8 core-shell heterostructure array.
- Utilized 13C isotope labeling spectroscopy and density functional theory (DFT) simulations to investigate the sensing mechanism.
- Optimized array configuration and shell thickness for enhanced localized electromagnetic fields.
Main Results:
- The Au@ZIF-8 sensor demonstrated an ultra-low limit of detection (LOD) of 0.16 ppt for formaldehyde.
- A 'guest-induced framework response' mechanism was identified, involving CH2O binding to defect sites, inducing linker torsion and bandgap narrowing.
- The sensor exhibited excellent linearity (R2 ≥ 0.99) from 0.01 ppb to 100 ppm and robust resistance to interferences like ethanol and toluene.
Conclusions:
- The developed Au@ZIF-8 core-shell heterostructure array provides a highly sensitive and selective platform for trace formaldehyde detection.
- The 'guest-induced framework response' mechanism in metal-organic frameworks offers a new strategy for molecular-level gas sensing.
- This approach establishes a new paradigm for the precise *in situ* monitoring of hazardous indoor VOCs, significantly advancing public health protection.
