Catalyst Formation and In Operando Monitoring of the Electrocatalytic Activity in Flow Reactors

Area of Science:

• Electrochemistry
• Materials Science
• Chemical Engineering

Background:

• Flow reactors are vital for chemical synthesis, hydrogen evolution, and wastewater treatment.
• Catalyst deactivation, often localized, limits the performance of flow electrolyzers.
• Transition-metal chalcogenides (TMCs) are key catalysts for the hydrogen evolution reaction (HER).

Purpose of the Study:

• To develop a spatially resolved *in operando* method for analyzing catalyst activity in flow reactors.
• To investigate localized catalyst deposition and track catalytic performance under real operational conditions.
• To provide detailed insights into catalyst behavior for flow reactor optimization.

Main Methods:

• Application of scanning electrochemical microscopy (SECM).
• Spatially resolved analysis (tens of micrometers) of catalyst activity.
• Localized tracking of transition-metal chalcogenide (TMC) activity with 25 μm resolution.
• Analysis of catalyst deposition in an operating model flow reactor.

Main Results:

• Demonstrated a method for *in operando* analysis of catalyst activity in flow reactors.
• Achieved spatially resolved tracking of catalyst deposition and activity.
• Successfully applied SECM for localized analysis of MoS₂ catalyst and TMC activity.
• Obtained detailed information on catalytic performance at the micrometer scale.

Conclusions:

• The developed method allows for high-resolution *in operando* characterization of flow reactor catalysis.
• This technique is valuable for understanding and optimizing catalyst performance under real operational conditions.
• The approach has broad applicability for the development and improvement of flow reactor systems.