Dr Seishi Shimizu’s success in Langmuir

News | Posted on Thursday 2 November 2023

An academic in the Department of Chemistry has had outstanding success with achieving 4 out of 20 of the “Most Read” articles in Langmuir, a leading international journal dealing with surface and colloid chemistry.

Seishi Shimizu in laboratory

Dr Seishi Shimizu is based at the York Structural Biology Laboratory (YSBL) and his recentresearch papers, which focus on sorption isotherms, have proved popular with the Langmuir readers.

Sorption isotherms are important in a range of disciplines and applications, such as how food moisture content and cement paste change with humidity, measurement of the porosity of materials, and the characterisation of battery electrodes. However, there have been some fundamental flaws in the way sorption analysis is carried out conventionally.

In collaboration with Professor Nobuyuki Matubayasi of Osaka University, Japan, Dr Shimizu has answered this question. Instead of adding yet another model to an already well-populated catalogue that exist already, they started from the fundamental principles of
statistical thermodynamics and established:

· the universal basic equations for sorption isotherms (valid for any surface shape and geometry, incorporating adsorption and absorption)

· a universal method to derive isotherms via differential equations

· capacity for modelling all six IUPAC isotherm types by the combination of only two statistical thermodynamic isotherms

The most popular isotherm models, Langmuir, BET, and GAB, are the special and restricted cases, based on idealized assumptions, of Dr Shimizu’s isotherm.

Dr Shimizu extended his theory further to sorption from solution, where the simplistic adaptation of the gas adsorption model precluded clarity for decades. Many of his theories have been made interactive, and are therefore usable for practitioners with their own data.

Dr Shimizu said: “I thank Professor Matubayasi for an incredibly fruitful long-term collaboration, Professor Steven Abbott for making the theory usable via his apps, and the York Structural Biology Laboratory for its stimulating interdisciplinary research environment. I am happy that there are still important problems to be tackled by pen and paper.”

The four Shimizu-Matubayasi papers that made it in the 20 Most Read articles (30 days) in Langmuir are:

· Understanding Sorption Mechanisms Directly from Isotherms, Langmuir, 2023, 39, 6113.

· Surface Area Estimation: Replacing the Brunauer–Emmett–Teller Model with the Statistical Thermodynamic Fluctuation Theory, Langmuir, 2022, 38, 7989.

· Sorption from Solution: A Statistical Thermodynamic Fluctuation Theory, Langmuir, 2023, 39, 12987.

· Cooperativity in Sorption Isotherms, Langmuir, 2023, 39, 13820.