Facile Synthesis of Carbon-Supported Ultrasmall Ag@Pd Core-Shell Nanocrystals with Superior Electrocatalytic Activity for Direct Formic Acid Fuel Cell Application

Preparation of Ni@Pd Core-Shell Nanoparticles Supported on KIT-6 by Ultrasound-Assisted Galvanic Replacement for Dodecahydro-N-ethylcarbazole Dehydrogenation

Using Ni as a template and reductant, Ni core-Pd shell nanoparticles (Ni@Pd NPs) supported on KIT-6 (Ni@Pd/K6) were prepared by a galvanic replacement reaction under ultrasonic radiation. The characterization results show that the Ni@Pd core-shell NPs with an average diameter of 1.9 ± 0.3 nm are uniformly dispersed on KIT-6. The d-band center position of Pd in Ni@Pd core-shell NPs can be affected by both ligand and strain effects. The relationship between the d-band center of Pd and the selectivity of intermediates is a nearly straight curve. The dehydrogenation efficiency of dodecahydro-N-ethylcarbazole on Ni@Pd(6:1)/K6 is 100% only for 3 h at 180 °C and 95.5% for 6 h at 160 °C, which is better than the reported catalysts. The outstanding catalytic dehydrogenation performance of Ni@Pd(6:1)/K6 can be attributed to the synergistic effect of the ligand and strain effect, the high dispersion of core-shell NPs, and the weak H2 binding ability of the catalyst.

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.