Adsorption of hydrogen on Au@Pd nanoparticles: DFT study

M. SANDOVAL; C. R. LUNA; E.A. GONZALEZ; A. O. PEREIRA; C. R. MIRANDA; P.V. JASEN; A. JUAN

Ankara

Simposio; mESC-IS 2015, International Symposium on Materials for Energy Storage and Conversion; 2015

Many experimental and theoretical researchers have been found that bimetallic nanoparticles (NPs) have interesting properties due to their structure, 3 like size, composition, chemical composition among others. Thus, our contribution in the study begins with the nanoparticle representation for the Au@Pd alloy for icosahedric structure with 1nm of size. Many different approximations for the H2 molecule to each adsorption site were studied. the lowest adsorption energy configurations were studied in detail: the BE_h2f-dE and HCPV_h2f-aB configurations with -1.44 eV -1.45 eV respectively. In general, for several sites, the H2 molecule is dissociated, showing dependence on orientation. Only the AE and AV sites do not exhibit this behavior. Also, an important difference in adsorption energy is found between sites for H2 is dissociated vs. non dissociated (among -1.30 eV and -1.46 eV for dissociated cases and between -0.06 eV and -0.62 eV for non dissociated cases). The obtained energies shows how important are the composition and the geometry of these nanoparticles. A preferential grow in a specific orientation should be studied when applications for hydrogen storage are considered.