Facile Synthesis of Pd-Ni Nanoparticles on Reduced Graphene Oxide under Microwave Irradiation for Formic Acid Oxidation

Rational Design of Highly Efficient PdIn-In2O3 Interfaces by a Capture-Alloying Strategy for Benzyl Alcohol Partial Oxidation

Well-dispersed PdIn bimetallic alloy nanoparticles (1-4 nm) were immobilized on mesostructured silica by an in situ capture-alloying strategy, and PdIn-In₂O₃ interfaces were rationally constructed by changing the In₂O₃ loading and reduction temperature. The catalytic performance for benzyl alcohol partial oxidation was evaluated, and a catalytic synergy was observed. The Pd-rich PdIn-In₂O₃ interface is prone to be formed on the catalyst with a low In₂O₃ loading after being reduced at 300 °C. It was demonstrated that the Pd-rich PdIn-In₂O₃ interface was more active for benzyl alcohol partial oxidation than In-rich Pd₂In₃ species, which was likely to be formed at a high reduction temperature (400 °C). The high catalytic activity on the Pd-rich PdIn-In₂O₃ interface was attributed to the exposure of more Pd-enriched active sites, and an optimized PdIn-In₂O₃/Pd assemble ratio enhanced the oxygen transfer during partial oxidation. The density functional theory (DFT) calculation confirmed that the Pd-rich Pd₃In₁(111)-In₂O₃ interface facilitated the activation of oxygen molecules, resulting in high catalytic activity.

A "Special" Solvent to Prepare Alloyed Pd2Ni1 Nanoclusters on a MWCNT Catalyst for Enhanced Electrocatalytic Oxidation of Formic Acid

Herein, an electrocatalyst with Pd₂Ni₁ nanoclusters, supporting multiwalled carbon nanotubes (MWCNTs) (referred to Pd₂Ni₁/CNTs), was fabricated with deep eutectic solvents (DES), which simultaneously served as reducing agent, dispersant, and solvent. The mass activity of the catalyst for formic acid oxidation reaction (FAOR) was increased nearly four times compared to a Pd/C catalyst. The excellent catalytic activity of Pd₂Ni₁/CNTs was ascribed to the special nanocluster structure and appropriate Ni doping, which changed the electron configuration of Pd to reduce the d-band and to produce a Pd-Ni bond as a new active sites. These newly added Ni sites obtained more OH^- to release more effective active sites by interacting with the intermediate produced in the first step of FAOR. Hence, this study provides a new method for preparing a Pd-Ni catalyst with high catalytic performance.

Recent Advances in Anode Electrocatalysts for Direct Formic Acid Fuel Cells - Part I - Fundamentals and Pd Based Catalysts

Direct formic acid fuel cells (DFAFCs) have gained immense importance as a source of clean energy for portable electronic devices. It outperforms other fuel cells in several key operational and safety parameters. However, slow kinetics of the formic acid oxidation at the anode remains the main obstacle in achieving a high power output in DFAFCs. Noble metal-based electrocatalysts are effective, but are expensive and prone to CO poisoning. Recently, a substantial volume of research work have been dedicated to develop inexpensive, high activity and long lasting electrocatalysts. Herein, recent advances in the development of anode electrocatalysts for DFAFCs are presented focusing on understanding the relationship between activity and structure. This review covers the literature related to the electrocatalysts based on noble metals, non-noble metals, metal-oxides, synthesis route, support material, and fuel cell performance. The future prospects and bottlenecks in the field are also discussed at the end.