Chinese researchers have made significant advancements in fuel cell technology, developing novel catalyst layers that dramatically reduce platinum requirements while simultaneously enhancing power output. These breakthroughs could address key barriers to the widespread adoption of hydrogen fuel cells, particularly their cost and reliance on the rare and expensive platinum group metal.
The recent discoveries demonstrate a strategic focus within China on making hydrogen fuel cells more affordable and efficient, aligning with the nation’s ambitious goal of achieving net-zero emissions by 2060.
Revolutionary Catalyst Layers Reduce Platinum Loading
A team of Chinese scientists has developed a new catalyst layer that significantly cuts oxygen transport resistance and minimizes power loss in proton exchange membrane fuel cells (PEMFCs). This innovation involves tweaking the interface of the catalyst with triazine-based covalent organic frameworks (COFs). The result is a remarkable 38% reduction in oxygen resistance and a stellar power density of 1.55 W/cm², achieved with an ultra-low platinum loading of just 0.05 mg_Pt/cm². This represents a 1.3x boost in power density compared to common designs using similar precious metal loadings, making the economics of hydrogen fuel cells more favorable. The research, published in Angewandte Chemie, was led by scientists including Prof. Min Wang, Dr. Quanbin Dai, Yilin Wang, Enyang Sun, Prof. Mingbo Wu, and Prof. Zhongtao Li.
Historically, a persistent challenge in PEMFCs since the 1960s has been poor oxygen movement at the triple-phase boundary, which is exacerbated by ionomer clumping and material deficiencies, particularly at high current densities. The new COF material tackles this issue by reshaping the cathode catalyst layer through interactions with Nafion’s sulfonate groups, creating a mesh of highly organized mesopores that facilitate oxygen delivery to the platinum. This approach maximizes platinum utility even with minuscule amounts.
Graphene-Encased Nano-Alloys for Green Hydrogen Production
Another significant development comes from a team at the Dalian Institute of Chemical Physics (DICP) and the University of Science and Technology of China (USTC). Under the leadership of Prof. Dehui Deng and Prof. Liang Yu, these researchers have engineered a cutting-edge graphene-encased cobalt-nickel (CoNi) nano-alloy catalyst. This catalyst dramatically reduces platinum use in proton exchange membrane (PEM) electrolysis for green hydrogen production.
The innovation lies in stabilizing single platinum atoms using an asymmetric π-electronic interface on graphene, allowing for high efficiency in hydrogen generation with significantly less platinum. The team achieved an incredibly low platinum loading of just 1.2 μgPt/cm² and demonstrated sustained operation for over 1,000 hours. To validate its industrial potential, a 2.85 kW PEM electrolyzer built with this catalyst operated stably for over 300 hours at an industrial current density of 1.5 A cm⁻². This breakthrough could be a game-changer for the hydrogen economy by making PEM electrolysis more cost-effective and scalable.
Platinum-Cobalt Alloys and High-Entropy Alloys
Further research from Chinese scientists has explored bimetallic catalysts to reduce platinum dependence. Researchers from the Beijing University of Technology and the Chinese Academy of Sciences have developed an innovative platinum-cobalt (PtCo) alloy on MXene, a layered material known for its conductivity and large surface area. This material combines a minuscule amount of platinum with cobalt, maintaining high catalytic performance while significantly reducing the need for expensive platinum, potentially making clean hydrogen production more practical for large-scale applications.
Additionally, a research team led by Prof. ZHANG Tierui from the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences (CAS) has developed a new catalyst composed of ultrafine platinum-based high-entropy alloy (HEA) octahedra. This catalyst significantly enhances the efficiency and durability of methanol oxidation reactions, addressing the issue of catalyst deactivation caused by poisoning species like carbon monoxide. By incorporating a diverse set of elements, they successfully reduced the surface energy of platinum-based nano-octahedra, allowing for the formation of stable structures with smaller sizes.
Addressing Key Challenges in Fuel Cell Commercialization
The high cost and limited availability of platinum have been significant barriers to the widespread commercialization of fuel cell electric vehicles. Platinum accounts for approximately 45% of the cost of a fuel cell. These Chinese innovations directly address these challenges by drastically lowering the platinum content required, which can lead to more affordable and sustainable fuel cell systems.
The ability to reduce platinum usage without sacrificing power output is crucial. Traditional methods to achieve high performance often involved stacking expensive membrane-electrode assemblies (MEAs) or oversizing the system, both of which were major cost drivers. The new COF-enhanced catalyst layer offers a path to achieving both high performance and affordability.
Broader Impact on the Hydrogen Economy
These advancements are particularly timely as China actively promotes hydrogen as a cornerstone of its future energy system and has seen explosive growth in its green hydrogen industry. Hydrogen fuel, especially for transportation and stationary backup, is a key component of China’s plan to reach net-zero emissions by 2060. By making fuel cells more cost-effective and resilient, these technologies could accelerate the transition away from fossil fuels and bolster China’s position in the global hydrogen economy. The benefits of this advanced catalyst engineering could also extend beyond PEMFCs to other electrochemical systems where oxygen supply limits performance, such as electrolyzers.