Abstract

We have developed a new adiabatic calorimetry system for enthalpy of gas absorption/adsorption process. The sample cell is designed to be extremely small as a calorimeter cell with a resistance thermometer; mass: 4.34 g, inner volume: 1.06 cc. A thin stainless steel tube is connected at the lid of the cell to introduce a gas. A gas handling system was also constructed to introduce a gas slowly and measure the amounts of the absorbed/adsorbed gas precisely via a pVT method. As the first work on this system, we measured the enthalpies of H2/D2 absorption into Pd nanoparticles with an average diameter of ca. 8 nm. The obtained values are ΔabsH(H) = –(18.15 ± 0.87) kJmol–1 and ΔabsH(D) = –(18.17 ± 0.38) kJmol–1 at 298 K. These values are considerably smaller than those of bulk Pd. The isotope effect are discussed semi-quantitatively on the basis of the potential energy surfaces at the H/D sites.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.