Advanced photon sources with nanoscale platinum grains open new ways to help hydrogen economy. Researchers at Argonne and Stanford University used bright X-rays to understand the factors necessary for hydrogen production.
A research team at the US Department of Energy’s (DOE) Argonne National Laboratory has used powerful X-ray beams to shed new light on what is important for the production and use of hydrogen. The goal is to make the production and use of hydrogen better and cheaper, thus providing a better fuel for transportation and industry.
“Efficient hydrogen production is key,” said Hoydoo You, senior scientist at Argonne. “Hydrogen is the simplest form of energy storage. Hydrogen can be produced from water using renewable or excess energy, transported as fuel and turned back into water to produce energy for consumers. Platinum and its alloys are excellent at promoting and stimulating the water dissociation process by promoting the exchange of electrons.
Understanding and developing the factors that allow the production and use of hydrogen is important for the hydrogen economy. Researchers have taken the first step in creating a tool that allows them to define the material at a new level of detail, ultimately creating the best material for the production and use of hydrogen. “It will make the production and use of hydrogen cheaper and more environmentally friendly,” you said.
The research team used the Advanced Photon Source (APS), a DOE Office of Science facility at Argonne. Working at APS, the researchers directed a large beam of X-rays at a single grain of platinum. The different patterns of this grain are collected in an X-ray detector. These values are converted to sample images using custom computer algorithms.
Nanodroplet chemical cells, made of small pipette tips (a device used to create small amounts of liquid), are used to control the chemical reactions that occur in platinum particles to produce hydrogen in an electrical device. An electric generator is a device for producing hydrogen from water using electricity; This reverse-engineering device, known as a fuel cell, converts hydrogen back into electricity.
“The reaction is controlled by applying a voltage, conducted through an electrolyte in a nano-pipette, to the grain being studied,” said Argonne physicist Matt Highland. He made this kind of new tool for the first time. This model enabled the study of a single nanograin and opened the way for energy analysis on the whole grain in an electrolyzer or fuel oil after the full APS upgrade. He also assisted in data collection and testing.
Argonne scientists Ross Harder and Wonsuk Cha worked at beamline APS 34-ID-C, where the experiments were conducted, and helped integrate new electronics into existing equipment. “The ability to do local electrochemistry where you’re creating a new picture of how things are going, at the level of one dimension, is amazing,” Harder said.
APS now provides X-rays up to a billion times brighter than those used by dentists. But a full upgrade will make APS even more powerful. When the upgraded APS comes online in 2024, its X-ray beam will be up to 500 times brighter than today. This means that techniques like the one used in this research will get even better after upgrading.
“The APS upgrade will help us see things happening in real time in hardware,” Harder said. “The measurement time can be so fast that we can go from one side to the other, and we will see how they interact in the electrochemical environment with each other.”
“Important processes like battery charging and corrosion require time-grain observations to understand the details of the process,” said Argonne Assistant Physicist Dina Sheyfer. “We believe that the added brilliance of APS enhancements and our new tools will enable studies we can only dream of today.”
Source: Argonne National Laboratory
