Probing the Accelerated Electron Transfer from Co to Fe within a Cyanide Framework Using Electrochemiluminescence
Jiaqi Gao1, Mingtong Cai1, Jian-Bin Pan1
1State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry, Nanjing University, Nanjing 210023, People's Republic of China.
Analytical Chemistry
|April 20, 2026
Summary
Cobalt doping in Prussian blue analogues enhances catalytic activity by facilitating electron transfer and radical generation. This breakthrough enables ultrasensitive single-particle imaging and sensitive biosensing applications.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- The catalytic performance of heterogeneous catalysts, such as Prussian blue analogues, is heavily influenced by the coordination environment of their metal centers.
- Understanding the structure-activity relationship at the single-particle level under operando electrochemical conditions is crucial but challenging.
Purpose of the Study:
- To investigate the exceptional catalytic activity of Cobalt-Iron Prussian blue analogues (CoFe-PBA) at the single-particle level.
- To elucidate the role of Cobalt doping in enhancing catalytic efficiency and enabling ultrasensitive electrochemiluminescence microscopy (ECLM).
Main Methods:
- Utilizing electrochemiluminescence microscopy (ECLM) for single-particle analysis.
- Employing density functional theory (DFT) calculations to understand electronic structure and reaction mechanisms.
- Developing an ECLM-based detection platform for alkaline phosphatase.
Main Results:
- DFT calculations revealed that Cobalt doping reduces the energy gap, facilitating electron transfer and accelerating interfacial electron transfer.
- This process activates a Fenton-like reaction at Cobalt sites, leading to the generation of radical oxygen species.
- Achieved exceptionally bright and stable single-particle ECLM imaging of CoFe-PBA and demonstrated sensitive alkaline phosphatase detection.
Conclusions:
- Engineered metal-center kinetics, specifically Cobalt doping, play a critical role in advancing ultrasensitive ECLM.
- The CoFe-PBA system exhibits significant potential for high-sensitivity analytical applications.
- This study provides a mechanistic understanding of single-particle catalysis and its application in advanced imaging and sensing.
