Direct solid state NMR observation of the¹⁰⁵Pd nucleus in inorganic compounds and palladium metal systems

Abstract

Although 105Pd is a very challenging nucleus for solid state NMR, these initial observations demonstrate its potential for characterising catalytically relevant Pd metal systems.

Interstitial Boron Atoms in the Palladium Lattice of an Industrial Type of Nanocatalyst: Properties and Structural Modifications

“…Furthermore, as the fast-relaxing component in this sample is not completely removed by the dilute HCl acid wash (conversely the slower sub-surface relaxing component is mostly removed), this fast-relaxing component is confidently attributed to the octahedral interstitial site within the bulk Pd metal framework. Recent reports have shown that 105 Pd solid state NMR can be a sensitive probe of very small deviations from FCC structural symmetry in Pd metal systems 18 . Hence, the newly reported 105 Pd VOCS static NMR methodology was applied to the Pdint B/C system and its undoped Pd/C precursor, to investigate the local distortion of the Pd lattice induced by interstitial B.…”

Investigating the structure–function relationship in triple cation perovskite nanocrystals for light-emitting diode applications

“…These observations mirror the findings from previous 195 Pt and 105 Pd NMR studies on Pt and Pd metal nanoparticle systems that report similar phenomena where the bulk component is clearly identified as a separate component to the disordered surface and sub-surface speciation of lower translational symmetry. [55][56][57] Fig . 1 High resolution transmission electron microscopy (HR-TEM) images of nanocrystals supporting, (a) 0 mol% Cs, (b) 5 mol% Cs, (c) 10 mol% Cs, and (d) 15 mol% Cs.…”

Recent progress in solid‐state nuclear magnetic resonance of half‐integer spin low‐γ quadrupolar nuclei applied to inorganic materials

“…However, referencing and calibrating the spectrometer can be a challenge, as was the case for 105 Pd. [35] Table 2 suggests some secondary standards for the low-γ nuclei being discussed here. In using solution references for some of these nuclei, quite a marked concentration dependence of the shift can occur, and this needs to be accounted for in taking some NMR parameters from the literature.…”

“…[103] As for conventional NMR, DNP studies have been dominated to date by 1 H and 13 C, with few applications to low-γ nuclei. However, examples do exist such as for 35 Cl in active pharmaceutical ingredients. The initial DNP step was to 1 H followed by CP to 35 Cl, where the bandwidth effects discussed above (Section 2.2) need to be overcome so that a 1 H- 35 Cl BRAIN-CP-WURST-CPMG (BCP) pulse sequence was used.…”

“…The initial DNP step was to 1 H followed by CP to 35 Cl, where the bandwidth effects discussed above (Section 2.2) need to be overcome so that a 1 H- 35 Cl BRAIN-CP-WURST-CPMG (BCP) pulse sequence was used. 35 Cl NMR powder patterns were acquired under static conditions, but a spinning-on/spinning-off acquisition protocol was also employed, with MAS during part of the sequence to increase the DNP enhancement and then stopped for static collection. Using this approach provided a further factor two signal enhancement, compared with DNP applied to purely static samples (Figure 5A).…”