Pd0@Polyoxometalate Nanostructures as Green Electrocatalysts: Illustrative Example of Hydrogen Production

Abstract

Green-chemistry type procedures were used to synthesize Pd0 nanostructures encapsulated by a vanadium-substituted Wells-Dawson-type polyoxometalate (Pd0@POM). The cyclic voltammogram run with the Pd0@POM-modified glassy carbon electrode shows well-defined waves, associated with Pd0 nanostructures and the VV/VIV redox couple. The Pd0@POM-modified electrode displayed remarkably reproducible cyclic voltammetry patterns. The hydrogen evolution reaction (HER) was selected as an illustrative example to test the electrocatalytic behavior of the electrode. The kinetic parameters of the HER show the high efficiency of the Pd0@POM-modified electrode. This is the first example of electrochemical characterization of a modified electrode based on a vanado-tungstic POM and Pd0 nanostructures.

Noble Metal‐Free Oxidative Electrocatalysts: Polyaniline and Co(II)‐Polyaniline Nanostructures Hosted in Nanoporous Silica

“…Electrocatalysts that are capable of catalyzing oxidation of organic compounds have enormous appeal because of their potential applications in fuel cells as well as organic syntheses 1, 2. Moreover, when used in chemical reactions for organic synthesis, oxidation electrocatalysts have advantages compared to conventional oxidation catalysts because the former enable ‘greener’ processes by avoiding the use of sacrificial oxidizing agents that often lead to undesired byproducts 3–5. However, despite these potential advantages, the use of electrochemical catalysts in oxidation reactions for synthetic purposes is not a very well explored research field.…”

Pristine Metal–Organic Frameworks and their Composites for Energy Storage and Conversion

“…The state‐of‐the‐art electrocatalysts for hydrogen production from water have always been the Pt‐based nanomaterials, whose widely utilization is hindered by the high cost and scarcity of Pt . POMs and their composites have been investigated as promising Earth‐abundant electrocatalysts for hydrogen evolution reaction, however, the high solubility and low surface area limited their electrochemical performance . In this regard, Dolbecq and co‐workers synthesized three POM‐based MOFs (POMOFs) by using tetrahedral ε‐Keggin POMs as node and 1,3,5‐benzenetricarboxylate as linkers .…”

POM & MOF‐based Electrocatalysts for Energy‐related Reactions

“…[104] This author also reported, in 2010, ag reen chemistry-type synthesis of Pd 0 nanostructures encapsulated by [H 4 V VI PW 17 O 62 ] 9À .T he Pd 0 @POM showedg ood HER performance with an overpotential h 10 = 0.034 Vv s. RHE to reach j = 10 mA cm À2 and TSs between 52-83 mV dec À1 . [109] More recently,Z hang et al have prepared active HER electrodes based on the lacunary SiW 11 and parentS iW 12 and P 2 W 18 POMs, with extremelyl ow Pt loadings in the range of 50-100 ng cm À2 . [107] The authors reportedt hat SiW 11 /Pt-modified GCE showedb est HER performance (in a0 .5 m H 2 SO 4 ), achieving aHER activity similar to Pt working electrode, with an overpotentialo fh 10 = 0.028 Vv s. RHE and aT So f3 2mVdec À1 .…”

“…This author also reported, in 2010, a green chemistry‐type synthesis of Pd 0 nanostructures encapsulated by [H 4 V VI PW 17 O 62 ] 9− . The Pd 0 @POM showed good HER performance with an overpotential η 10 =0.034 V vs. RHE to reach j =10 mA cm −2 and TSs between 52–83 mV dec −1 …”