Showing posts with label fuel cell. Show all posts
Showing posts with label fuel cell. Show all posts

Thursday, June 29, 2023

Revolutionizing Fuel Cell Catalysts: Enhanced Durability and Performance with Platinum-Modified Tungsten Oxide Support

Breakthrough Study Utilizes Atomic Layer Deposition and Ar Plasma Treatment for Highly Robust Anode Catalysts in Polymer Electrolyte Membrane Fuel Cells

Key Findings:

1. Tungsten oxide (WO3) supported catalysts, enhanced through Ar plasma surface treatment and Pt nanoparticle deposition using atomic layer deposition (ALD), demonstrated significantly improved durability in diverse operating conditions compared to commercial Pt/C catalysts.

2. The use of WO3 as a catalyst support material, coupled with ALD-based Pt nanoparticle deposition, offers a promising approach for developing high-performance anode catalysts for polymer electrolyte membrane fuel cells (PEMFCs) with enhanced stability and performance.

In an article titled "Atomic layer deposited platinum on tungsten oxide support as high-performance hybrid catalysts for polymer electrolyte membrane fuel cells" Korean researchers discuss the development of a robust anode catalyst for polymer electrolyte membrane fuel cells (PEMFCs). The researchers aimed to address the performance degradation and carbon support corrosion issues commonly observed in PEMFCs under harsh operating conditions.


Graphical abstract

The study focused on using tungsten oxide (WO3) as a catalyst support material due to its ability to provide additional hydrogen ions and electrons through the decomposition of tungsten bronze (HxWO3) formed by the hydrogen spillover effect. The presence of HxWO3 also helped stabilize the cell potential by scavenging oxygen that infiltrates into the anode during start-up and shut-down situations. However, the low electrical conductivity of metal oxides can lead to initial performance degradation.

To overcome this limitation, the researchers performed Ar plasma surface treatment on the WO3 layer to enhance its electrical conductivity. This treatment, known as P-WO3, increased the density of electrons, enabling n-doped conduction. Next, platinum (Pt) nanoparticles were deposited on the P-WO3 support using atomic layer deposition (ALD). ALD allowed for the controlled deposition of Pt at the nanoscale, maximizing the catalytic activity with a minimal amount of precious metal.

The resulting Pt/P-WO3 catalyst exhibited significantly enhanced durability compared to commercial Pt/C catalysts under diverse operating conditions. It demonstrated improved performance and acted as a reversal-tolerant anode catalyst. The study highlights the potential of using WO3 as a support material and the effectiveness of the proposed fabrication method in developing high-performance catalysts for PEMFCs.

Overall, the article presents a novel approach to address the challenges associated with catalyst performance and carbon support corrosion in PEMFCs. By utilizing WO3 as a support material and incorporating Pt nanoparticles through ALD, the researchers achieved an improved and durable anode catalyst for PEMFCs.

The academic institutions behind the article are:

1. Department of Automotive Convergence, Korea University, Republic of Korea.

2. School of Mechanical Engineering, Korea University, Republic of Korea.

Source: Atomic layer deposited platinum on tungsten oxide support as high performance hybrid catalysts for polymer electrolyte membrane fuel cells - ScienceDirect

Wednesday, March 26, 2014

ALD saving the sunshine for night: solar fuels from artificial photosynthesis

As reported by Thomas Meyer and Ralph House "Saving the sunshine for night: solar fuels from artificial photosynthesis", direct visible light water splitting in a dye-sensitized photoelectrosynthesis cell makes hydrogen for energy storage. Key findings using a stable catalyst is reported by binding on the surface of conducting nano ITO electrodes, they first bind the catalyst to the surface and then stabilize it by ALD of a TiO2 overlayer to prevent hydrolysis.

Dye-sensitized photoelectrosynthesis cell (DSPEC) for water splitting. The inset illustrates the surface-bound chromophore-catalyst assembly (shown as orange dots on the spherical nanoparticles in the core/shell film). H2O: Water. O2: Oxygen. H2: Hydrogen. H+: Hydrogen cation. (Graphic by Yan Liang, L2Molecule.com, as reported in the SPIE news blog)


Read all about it here or check out the original work in these refrences:

T. J. Meyer, J. M. Papanikolas, C. M. Heyer, Solar fuels and next generation photovoltaics: the UNC-CH Energy Frontier Research Center, Cat. Lett. 141(1), p. 1-7, 2011. doi:10.1007/s10562-010-0495-9
 
R. House, L. Alibabaei, C. Bonino, P. Hoertz, J. Trainham, T. J. Meyer, Let the molecules do the work, PV Magazine 03/2013, p. 87-89, 2013.
 
A. K. Vannucci, L. Alibabaei, M. D. Losego, J. J. Concepcion, B. Kalanyan, G. N. Parsons, T. J. Meyer, Crossing the divide between homogeneous and heterogeneous catalysis in water oxidation, Proc. Nat'l Acad. Sci. USA 110(52), p. 20918, 2013. doi:10.1073/Pnas.1319832110
 
L. Alibabaei, M. K. Brennaman, M. R. Norris, B. Kalanyan, W. J. Song, M. D. Losego, J. J. Concepcion, R. A. Binstead, G. N. Parsons, T. J. Meyer, Solar water splitting in a molecular photoelectrochemical cell, Proc. Nat'l Acad. Sci. USA 110(50), p. 20008, 2013. doi:10.1073/Pnas.1319628110