Tribochemically driven dehydrogenation of undoped sodium alanate under room temperature

Abstract

An application of mechanical energy was explored as a new non-thermal method to drive H2 emission from undoped sodium alanate at room temperature. It was found that mild rubbing of...

Operando exploration of tribochemical decomposition in synthetic FeS2 thin film and mineral iron pyrite

“…Furthermore, quick response of gas emission to both the beginning and the end of mechanical solicitation in all behaviour modes highlights that emission was predominantly controlled by fast processes. 38 This contrasts the data obtained for metals and hydrides, which usually demonstrate retarded or trail emission due to a significant (up to 20%) contribution from slow processes such as diffusion and migration. 29,100,101 Fast emission kinetics reduces the constraints for processing the gas emission data and facilitates deconvolution of the mass-spectrometry time series into the evolution of mechanochemical activation and the progression of chemical reactions.…”

“…From the perspective of mechanochemistry, the driving forces of tribochemical gas emission can be linked to stress, strain or secondary physico-chemical activation processes such as the emission of charged particles, luminescence, the generation and motion of active sites and defects in a crystalline structure, and so on, though the specic mechanism governing tribochemical decomposition of FeS 2 is not clear yet. 14,38,[103][104][105][106] Literature provides evidence that stress or strain exerted by mechanical action can directly couple to the energy landscape of a chemical reaction or can modify it locally, thus reducing potential barriers. 23,107,108…”

“…[27][28][29] Up to now, mass spectrometry of emitted gases has been successfully employed across various studies, revealing tribochemical processes within diverse materials such as amorphous carbon, 30,31 polymers, 32 metal alloys, 29,33 minerals [34][35][36][37] and hydrides. 33,38 In the present study, our focus is on investigating the tribochemical processes on the submicrometre scale in two forms of iron sulde: natural mineral and synthetic thin lm. We employed MSGE-MS to gain a comprehensive understanding of these processes.…”