Metrology and Analysis

Differential Electrochemical Mass Spectrometry (DEMS) is an analytical technique that combines electrochemical half-cell experimentation with mass spectrometry.

It allows in situ mass resolved determination of gaseous or volatile electrochemical reactants, reaction intermediates and products in real time.

The experimental setup consists of an electrochemical half-cell, the membrane interface and a vacuum system including a quadrupole mass spectrometer.

DEMS is closely related to membrane inlet mass spectrometry (MIMS).

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This is a re-post of an article published by Hiden Analytical in October 2020. IES Technical Sales represents Hiden Analytical in the six New England states of the U.S. Please
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Catalysis is the process of modifying a chemical reaction with the use of a catalyst. This process only works with chemicals that have an existing reaction, and it is used to accelerate the reaction for commercial purposes. Catalysis occurs faster than a standard chemical reaction because catalysts require less activation energy, which is the minimum level of energy necessary to initiate a chemical reaction.

This blog post will outline the principle of catalysis and the different types.

Catalysis Working Principle

Temperature Programmed Oxidation (TPO) is an analytical technique capable of characterizing catalysts and is an important consideration for research and development.

The performance of TPO requires a furnace or microreactor capable of increasing temperatures of a catalyst in precise increments up to extreme conditions, for example in brackets of 1-20°C min^-1 up to 1000°C. An integrated mass spectrometer allows for constant real-time analysis of catalytic activity throughout a given thermal reaction, in which a gas mixture will flow over a catalyst throughout an incrementally programmed temperature rise.

Temperature programmed reduction (TPR) is a material characterization process commonly used in catalysis studies to examine the surface chemistry of metals and metal oxides under varying thermal conditions. TPR-enabled mass spectrometry equipment can acquire quantitative and qualitative data relating to the reducing gas mixtures that are made to flow over metallic samples. This process is integral to catalyst investigation as it provides accurate insights into catalyst reducibility and reaction rates in the presence of metal surfaces, informing conclusions on catalyst reproducibility and supporting quality control of existing catalytic substances by setting benchmarks or reduction profiles that ideal manufactured catalysts should adhere to.

This is a re-post of an article published by Hiden Analytical of Warrington, England.

In materials science, a surface interface refers to the boundary region between air or a vacuum and physical media. The atomic composition and topography of a solid’s surface monolayer can determine many of the chemical-mechanical characteristics of the bulk material, including solid—gas interfaces such as adsorption and permeation. Reaction kinetics of catalysts and the electromechanical performance of semiconducting materials for thin film fabrication are both affected by surface interface phenomena.

Modern surface engineers consider surface interface analysis a critical stage of development and process control. This article will explore how surface interface analysis is performed in more detail, while highlighting some of its critical applications:

Catalysis is the process of modifying a chemical reaction with the use of a catalyst. This process only works with chemicals that have an existing reaction, and it is used to accelerate the reaction for commercial purposes. Catalysis occurs faster than a standard chemical reaction because catalysts require less activation energy, which is the minimum level of energy necessary to initiate a chemical reaction.

Catalysis Working Principle

When a chemical is placed with a compatible catalyst, there is a reduction in the free energy required for the chemical to reach the transition state for that particular reaction. Catalysts can influence the reaction environment, depending on the specific reaction requirements.

For example, catalysts can produce more heat, form specific

The Suib Group at the University of Connecticut collaborated with Hiden Analytical to determine the effectiveness of Hiden’s Compact SIMS (Secondary Ion Mass Spectroscopy) Analysis System for various research applications, including:

• Surface Contamination on Silver Electrodes
• Catalyst Dopant Homogeneity
• Carbon Contamination and Removal via heat treatment
• Urethane Tubing Chemical Attack

For the detailed experiment findings, click here.

Residual Gas Analyzers (RGAs) are quadrupole mass spectrometers that provide for routine, fast, wide dynamic range measurements of the partial pressures of the species resident in your vacuum chamber or system. Vacuum levels can be analyzed from as low as 10-14 Torr to as high as 10-3 Torr depending on the type of analyzer design. Analysis at higher chamber pressures can be accomplished by connecting your RGA to a differential pumping system.

Applications include:

• Vacuum chamber leak detection
• Vacuum quality measurement and monitoring
• Virtual leak detection (water, contaminants, cleaning agents, etc.)
• Outgassing studies
• Bakeout cycle/vacuum pump down monitoring

Measurement is accomplished by ionizing the gas molecules exposed to the sensor, sending