Massive Pressure Amplification by Stimulated Contraction of Mesoporous Frameworks**

Abstract

Herein we demonstrate mesoporous frameworks interacting with carbon dioxide leading to stimulated structural contractions and massive out‐of‐equilibrium pressure amplification well beyond ambient pressure. Carbon dioxide, a non‐toxic and non‐flammable working medium, is promising for the development of pressure‐amplifying frameworks for pneumatic technologies and safety systems. The strong interaction of the fluid with the framework even contracts DUT‐46, a framework hitherto considered as non‐flexible. Synchrotron‐based in situ PXRD/adsorption experiments reveal the characteristic contraction pressure for DUT‐49 pressure amplification in the range of 350–680 kPa. The stimulated framework contraction expels 1.1 to 2.4 mmol g−1 CO2 leading to autonomous pressure amplification in a pneumatic demonstrator system up to 428 kPa. According to system level estimations even higher theoretical pressure amplification may be achieved between 535 and 1011 kPa.

Charting the Complete Thermodynamic Landscape of Gas Adsorption for a Responsive Metal–Organic Framework

“… 7 This leads to pressure amplification in a closed system, opening the door to new applications. 8 The lack of thermodynamic understanding of the NGA phenomenon has motivated a number of computational studies. 9 , 10 However, efforts have mostly relied on two-state models that are unable to capture the complete phase-space during adsorption and desorption.…”

“…This MOF undergoes a structural transition associated with a 50% contraction of the unit cell upon increasing methane gas pressure, resulting in spontaneous desorption of methane . This leads to pressure amplification in a closed system, opening the door to new applications . The lack of thermodynamic understanding of the NGA phenomenon has motivated a number of computational studies. , However, efforts have mostly relied on two-state models that are unable to capture the complete phase-space during adsorption and desorption …”