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

Abstract

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.

Facile Synthesis of the TiO2-Supported Ultrathin Palladium Facet Composite Catalyst with Superior Metal Dispersion and Enhanced Catalytic Performance in Formic Acid Electro-Oxidation

“…Direct formic acid fuel cells (DFAFCs) are a well-known sustainable power source in transportation and portable electronic devices because of their efficient and clean energy supply. ,,− The development of an active anodic catalyst for formic acid electro-oxidation, which is the key reaction of DFAFCs, is an active research field. Supported Pd catalysts with high metal loadings have been verified to be preferred catalysts in formic acid oxidation since Pd is less vulnerable to being poisoned by strongly adsorbed CO ads reaction intermediates as compared to Pt because of the dominance of the direct formic acid oxidation path. ,, As compared to carbon support, which usually undergoes corrosion/oxidation in harsh fuel cell environments, the TiO 2 support is a more preferable candidate to use because of its high thermal and chemical stabilities in acidic and oxidative environments . Therefore, the catalytic properties of our as-prepared TiO 2 (001)@Pd­(111) catalyst were tested by utilizing formic acid oxidation as the probe reaction.…”

“…Supported metal catalysts have been extensively applied in pharmaceutics, environmental protection, the petrochemical industry, and new sources of energy. − The development of an effective supported metal catalyst exhibiting high activity and stability is always a central issue in current catalytic research. However, the agglomeration of metal nanoparticles in the supported metal catalyst is still a big problem, which usually causes the deactivation of the catalysts .…”

Reviews on Homogeneous and Heterogeneous Catalysts for Dehydrogenation and Recycling of Formic Acid: Progress and Perspectives

“…Characterization of DFAFC anode electrocatalysts . Reproduced with permission from ref . Copyright 2022, John Wiley and Sons.…”

“…Pd and Pt are catalysts often used in PEMFCs, but Pt is difficult to commercialize on account of the high cost and low storage capacity of the fuel cells it produces . The cathodic redox reaction in fuel cells has a slow reaction kinetics for Pt.…”

Curved Porous PdCu Metallene as a High-Efficiency Bifunctional Electrocatalyst for Oxygen Reduction and Formic Acid Oxidation

“…However, their high manufacturing costs and inferior stability impede the large-scale commercial production of fuel cells. , Palladium is a metal that belongs to the platinum group of noble metals and has the benefits of great abundance, methanol resistance, and so on. It is projected to be a highly efficient bifunctional electrocatalyst to replace platinum. − However, palladium has a significant oxygen binding force and can be oxidized at a relatively negative potential, resulting in decreased oxygen reduction activity. Therefore, the performance of a onefold palladium metal in the catalytic process is inadequate .…”