The transition to sustainable energy sources has become imperative due to the exhaustion of conventional resources caused by excessive use and their detrimental impact on the environment. Currently, alternative energy sources, such as solar, wind, nuclear, tidal, and geothermal energy, hydro have been introduced. Over the last few decades, focus has shifted to the use of hydrogen energy as a promising alternative to traditional power sources in almost all sectors requiring energy applications.

However, a major challenge holding back their widespread use is the high cost and limited performance of a key component called the catalyst layer (CL). This layer is responsible for speeding up the chemical reaction that generates electricity, but it typically requires a large amount of platinum, a rare and expensive metal and often has a thick, disordered structure that reduces efficiency.

This research, titled “Towards Next-Generation proton exchange membrane fuel Cells: The role of nanostructured catalyst layers” led by Dr. Narayanamoorthy Bhuvanendran, Assistant Professor, Department of Environmental Science and Engineering, was published in the Q1 Journal, Chemical Engineering Journal, with an Impact Factor of 13.4. The paper focuses on designing advanced nanostructured catalyst layers that are thinner, more organised, and use much less platinum. These next-generation CLs can help fuel cells perform better, last longer, and become more affordable.

The study reviews recent progress in this field, highlights innovative methods for creating these new structures, and outlines future directions to improve their practicality and environmental impact. Ultimately, this work aims to bring us closer to clean, efficient, and widely accessible fuel cell technology.

Fuel cells offer clean energy with zero emissions when using hydrogen, and higher energy efficiency than diesel or gas engines. Among them, Proton Exchange Membrane Fuel Cells (PEMFCs) are one of the most promising technologies. PEMFCs produce only water as a byproduct, making them a clean energy alternative to fossil fuels.

Abstract:
Catalyst layer (CL) is the major component of proton exchange membrane fuel cells (PEMFCs) and routinely fabricated by a catalyst ink-based processing method. Such conventional CLs typically confront low activity, unaffordable Pt loading, and severe mass transport issues due to the thick and disordered structure, hampering the widespread commercial application of PEMFCs.

Engineering of nanostructured CLs with low/ultralow Pt loading, ordered and/or ultrathin CLs, provides a highly promising pathway for overcoming these limitations. For the practical application of the nanostructured CLs in PEMFCs, this review comprehensively summarises and comments on the important research and development of nanostructured CLs over recent years, involving ordered electronic conductor-based CLs, ordered ionomer-based CLs, and ultrathin CLs.

The reviewed processes include

(i) analysing the motivation and necessity to design and fabricate nanostructured CLs based on the structure and mass transport process of conventional CLs,
(ii) scrutinising structure and composition, preparation methods, advantages, as well as
some feasible strategies for the remaining challenges of various nanostructured CLs in
detail,
(iii) the progress of single cell activity and durability of the nanostructured CLs. Finally, some perspectives on remaining challenges and future development of the nanostructured CLs are presented to guide the exploitation for the next-generation of advanced CLs of PEMFCs.

Practical implementations:

The practical objective of this study is to facilitate the development of more efficient, cost-effective, and durable proton exchange membrane fuel cells (PEMFCs) through the redesign of the catalyst layer utilising advanced nanostructures. This enhancement has the potential to substantially decrease dependence on costly platinum, reduce production expenses, and enhance the overall performance of fuel cells.

In terms of societal impact, this research contributes to the transition towards clean and sustainable energy systems, thereby reducing greenhouse gas emissions and air pollution associated with conventional fossil fuels. By making fuel cell technology more accessible and scalable, particularly for transportation and portable power applications, it supports global initiatives to combat climate change and improve energy security for future generations.

Collaborations:
Prof. Huaneng Su, Institute for Energy Research, Jiangsu University, Zhenjiang, China.