TY - JOUR
T1 - The Nature of Hydrogen Adsorption on Platinum in the Aqueous Phase
AU - Yang, Guoju
AU - Akhade, Sneha A.
AU - Chen, Xi
AU - Liu, Yue
AU - Lee, Mal Soon
AU - Glezakou, Vassiliki Alexandra
AU - Rousseau, Roger
AU - Lercher, Johannes A.
PY - 2019/3/11
Y1 - 2019/3/11
N2 - The thermodynamic state of H 2 adsorbed on Pt in the aqueous phase was determined by kinetic analysis of H 2 reacting with D 2 O to HDO, HD, and D 2 , and by DFT-based ab initio molecular dynamics simulations of H 2 adsorption on Pt(111), Pt(110), and Pt nanoparticles. Dissociative adsorption of H 2 on Pt is significantly weakened in the aqueous phase compared to adsorption at gas–solid interfaces. Water destabilizes the adsorbed H atoms, decreasing the heat of adsorption by 19–22 kJ (Formula presented.) while inducing an additional entropy loss of 50–70 J (Formula presented.) K −1 . Upon dissociative adsorption of H 2 , the average distance of water from the Pt surface increases and the liquid adopts a structure that is more ordered than before close to the Pt surface, which limits the translation mobility of the adsorbed H atoms. The presence of hydrated hydronium ions next to the Pt surface further lowers the H−Pt bond strength.
AB - The thermodynamic state of H 2 adsorbed on Pt in the aqueous phase was determined by kinetic analysis of H 2 reacting with D 2 O to HDO, HD, and D 2 , and by DFT-based ab initio molecular dynamics simulations of H 2 adsorption on Pt(111), Pt(110), and Pt nanoparticles. Dissociative adsorption of H 2 on Pt is significantly weakened in the aqueous phase compared to adsorption at gas–solid interfaces. Water destabilizes the adsorbed H atoms, decreasing the heat of adsorption by 19–22 kJ (Formula presented.) while inducing an additional entropy loss of 50–70 J (Formula presented.) K −1 . Upon dissociative adsorption of H 2 , the average distance of water from the Pt surface increases and the liquid adopts a structure that is more ordered than before close to the Pt surface, which limits the translation mobility of the adsorbed H atoms. The presence of hydrated hydronium ions next to the Pt surface further lowers the H−Pt bond strength.
KW - adsorption
KW - hydrogen
KW - hydrogen binding energy
KW - platinum
KW - water phase
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U2 - 10.1002/anie.201813958
DO - 10.1002/anie.201813958
M3 - Article
C2 - 30556940
AN - SCOPUS:85060807109
VL - 58
SP - 3527
EP - 3532
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
SN - 1433-7851
IS - 11
ER -