Methanol tolerant oxygen-reduction activity of carbon supported platinum–bismuth bimetallic nanoparticles

Adsorbed Carbon Monoxide-Enabled Self-Terminated Au-Grafting on Pt6 Nanoclusters for Enhanced Methanol Electrooxidation

The study presents the first example of an adsorbed carbon monoxide (CO) enabled self-terminated Au-grafting on triphenylphosphine (PPh3) stabilized Pt6 nanoclusters (NCs) (Pt6 (PPh3)4Cl5 NCs or Pt6 NCs). Adsorbed PPh3 ligands weaken the Pt-CO bond enabling the self-terminated Au-grafting on Pt6 NCs. The Au-grafted Pt6 NCs exhibit enhanced methanol electrooxidation (MOR) in acidic solutions. The surface is composed of a PtAu ensemble exhibiting enhanced MOR and CO tolerance due to the synergistic interaction of Pt with Au and PPh3. The hydrogen underpotential deposition (H-UPD) signal from a CO-covered surface reveals the existence of free-Pt sites on the PtAu ensemble causing higher MOR reactivity. The Au and PPh3 ensure electrocatalytic activity of the NCs, depriving of them at anodic potentials results in "a death-valley" trend.

Colloidal chemical bottom-up synthesis routes of pnictogen (As, Sb, Bi) nanostructures with tailored properties and applications: a summary of the state of the art and main insights

Adjusting the colloidal chemistry synthetic parameters for pnictogen nanostructures leads to a fine control of their physical properties and the resulting performance in applications. Image adapted from Slidesgo.com.

Bismuth oxide nanoparticles as a nanoscale guide to form a silver–polydopamine hybrid electrocatalyst with enhanced activity and stability for the oxygen reduction reaction

High dispersion Ag nanoparticles were successfully synthesized on functionalized polydopamine@Bi₂O₃ NPs for use as electrocatalyst. Synergetic effect was found to enhance the catalytic ability for direct 4e⁻ transfer in oxygen reduction reaction.

Improved oxygen reduction reaction catalyzed by Pt/Clay/Nafion nanocomposite for PEM fuel cells

A novel Pt nanoparticle (Pt NP) embedded aminoclay/Nafion (Pt/AC/N) nanocomposite catalyst film was prepared for oxygen reduction reaction by sol-gel method. The prepared nanocomposite films were surface characterized using XRD and TEM and thermal stability was studied by TGA. The prepared film has firmly bound Pt NP and could exhibit an improved electro-reduction activity compared to vulcan carbon/Nafion supported Pt NP (Pt/VC/N). Moreover, the Pt/AC/N film possessed good stability in the acidic environment. The limiting current density of the Pt/AC/N film with 35.4 μg/cm(2) of Pt loading was found to be 4.2 mA/cm(2), which is 30% higher than that of the Pt/VC/N. The maximum H2O2 intermediate formation was found to be ∼1.6% and the reaction found to follow a four electron transfer mechanism. Accelerated durability test for 2000 potential cycles showed that ca. 78% of initial limiting current was retained. The results are encouraging for possible use of the Pt/AC/N as the free-standing electrocatalyst layer for polymer electrolyte membrane fuel cells.