Lunar Soil Can Be Used To Generate Oxygen and Fuel for Moon Astronauts

An artist’s impression of what a lunar base could look like. Scientists exploring whether lunar resources can be used to facilitate human exploration on the moon or beyond have reported that lunar soil contains active compounds that can convert carbon dioxide into oxygen and fuels. Credit: ESA – P. Carril

Soil on the moon contains active compounds that can convert carbon dioxide into oxygen and fuels, according to a new study by scientists in China that was published on May 5, 2022, in the journal Joule. They are currently investigating whether lunar resources can be used to facilitate human exploration on the moon or beyond.

Nanjing University material scientists Yingfang Yao and Zhigang Zou hope to design a system that takes advantage of lunar soil and solar radiation, the two most abundant resources on the moon. After analyzing the lunar soil brought back by China’s Chang’e 5 spacecraft, their research team found the sample contains compounds—including iron-rich and titanium-rich substances—that could work as a catalyst to make desired products such as oxygen using sunlight and carbon dioxide.

This photograph shows a lunar soil sample returned by China’s Chang’e 5 spacecraft. Credit: Yingfang Yao

Based on the observation, the team proposed an “extraterrestrial photosynthesis” strategy. Mainly, the system uses lunar soil to electrolyze water extracted from the moon and in astronauts’ breathing exhaust into oxygen and hydrogen powered by sunlight. The carbon dioxide exhaled by moon inhabitants is also collected and combined with hydrogen from water electrolysis during a hydrogenation process catalyzed by lunar soil.

The process yields hydrocarbons such as methane, which could be used as fuel. The strategy uses no external energy but sunlight to produce a variety of desirable products such as water, oxygen, and fuel that could support life on a moonbase, the researchers say. The team is looking for an opportunity to test the system in space, likely with China’s future crewed lunar missions.

This schematic shows how lunar soil can work as a catalyst for extraterrestrial photosynthesis to make oxygen and fuels needed for long-term survival on the moon. Credit: Yingfang Yao

“We use in-situ environmental resources to minimize rocket payload, and our strategy provides a scenario for a sustainable and affordable extraterrestrial living environment,” Yao says.

While the catalytic efficiency of lunar soil is less than catalysts available on Earth, Yao says the team is testing different approaches to improve the design, such as melting the lunar soil into a nanostructured high-entropy material, which is a better catalyst.

This video shows photovoltaic-driven water electrolysis catalyzed by lunar soil. Credit: Yingfang Yao

Previously, scientists have proposed many strategies for extraterrestrial survival. But most designs require energy sources from Earth. For example, Lunar Soil Can Be Used To Generate Oxygen and Fuel for Moon Astronauts