In the quest for more efficient and durable energy solutions, researchers have made a significant stride in enhancing the performance of proton exchange membrane water electrolysis (PEMWE) cells. A recent study published in *Applied Surface Science Advances* (translated from Chinese as *Advances in Applied Surface Science*) introduces a novel approach to coating bipolar plates (BPs), a critical component in PEMWE cells. The research, led by Jianping Gao from the State Key Laboratory for Mechanical Behavior of Materials at Xi’an Jiaotong University and Western Metal Materials Co., Ltd., focuses on TiONx/TiN composite coatings that promise to revolutionize the energy sector.
Bipolar plates are essential for the efficient operation of PEMWE cells, which are used to produce hydrogen through water electrolysis. However, these plates often face challenges such as corrosion and poor electrical conductivity, which can hinder performance and longevity. The study addresses these issues by developing a coating method that combines anodizing and in-situ plasma nitriding for TiONx and magnetron sputtering for TiN. This method results in a coating with a remarkably small lattice mismatch of only 1.37%, significantly better than the 8.88% mismatch between TiO2 and TiN.
“This small lattice mismatch ensures strong interface adhesion strength, which is crucial for the durability of the coatings,” explains Jianping Gao. The coatings not only exhibit enhanced corrosion resistance, with a corrosion current density of 0.17 μA·cm-2, but also high electrical conductivity of 6.75 mΩ·cm2 at 1.5 MPa. After 300 hours of potentiostatic testing at 2 V, the TiONx/TiN coating maintained a low corrosion current density of 4.6 μA·cm-2 and an interface contact resistance (ICR) of 23.64 mΩ·cm2.
The practical implications of this research are substantial. In cell assembly tests, the TiONx/TiN-coated BPs demonstrated lower ICR and higher electrolysis efficiency (77.89%) compared to uncoated BPs (64.35%). This improvement in efficiency and durability could significantly impact the energy sector, making PEMWE cells more viable for large-scale hydrogen production.
“The potential of this coating technology is immense,” says Gao. “It could lead to more efficient and cost-effective hydrogen production, which is a key goal for the energy industry.”
As the world continues to seek sustainable energy solutions, advancements like these are crucial. The research highlights the importance of innovative materials and coating techniques in enhancing the performance of energy technologies. With further development, the TiONx/TiN composite coatings could become a standard in the industry, paving the way for more efficient and reliable PEMWE cells.
This study, published in *Applied Surface Science Advances*, marks a significant step forward in the field of energy materials science. As the energy sector continues to evolve, such breakthroughs will be essential in meeting the growing demand for clean and sustainable energy solutions.