A group affiliated with the University of Science and Technology of China (USTC), a part of the Chinese Academy of Sciences, has achieved the automated synthesis and optimization of oxygen evolution reaction (OER) catalysts derived from Martian meteorites. This breakthrough was reported in the journal Nature Synthesis.
The newfound optimism stems from the revelation of aquatic activity on Mars. Scientists are now contemplating the prospect of extracting oxygen by breaking down water, leveraging OER catalysts. The primary challenge lies in developing a method to produce these catalysts on Mars itself, utilizing local materials, as opposed to the costly transportation of such materials from Earth.
In response to this challenge, a team led by Professors LUO Yi, JIANG Jun, and SHANG Weiwei, associated with the USTC at the Chinese Academy of Sciences (CAS), has successfully automated the synthesis and optimization of OER catalysts using Martian meteorites. Their chemical robot, equipped with artificial intelligence (AI), played a pivotal role in this achievement.
They are investigating the potential of utilizing OER catalysts to decompose water and generate oxygen.
"Through interdisciplinary collaboration, the AI chemist creatively synthesizes OER catalysts from Martian substances," stated Professor LUO Yi, the team's lead scientist.
In each experimental iteration, the AI chemist initiates the process by scrutinizing the elemental composition of Martian minerals, employing laser-induced breakdown spectroscopy (LIBS) as its visual aid.
Subsequently, it undergoes a series of mineral pretreatments, encompassing tasks such as weighing at the solid dispensing workstation, crafting raw material solutions at the liquid dispensing workstation, and segregating liquids into the centrifugation workstation, followed by solidification in the drying workstation.
The resultant metal hydroxides undergo treatment with Nafion adhesive, facilitating the preparation of the working electrode essential for OER testing at the electrochemical workstation. Real-time test data is transmitted to the computational "brain" of the AI chemist for processing through machine learning (ML).
The AI chemist's "brain" employs quantum chemistry and molecular dynamics simulations on 30,000 high-entropy hydroxides, each with distinct elemental ratios. Using density functional theory, it computes their OER catalytic activities. The simulation data is utilized to train a neural network model, enabling swift predictions of catalyst activities for various elemental compositions.
Ultimately, through the application of Bayesian optimization, the "brain" forecasts the optimal combination of accessible Martian minerals required to synthesize the most effective OER catalyst.
This catalyst demonstrates an impressive continuous operation exceeding 550,000 seconds.
Under unmanned conditions, the AI chemist has successfully engineered an exceptional catalyst using a blend of five types of Martian meteorites. This catalyst exhibits sustained functionality for over 550,000 seconds at a current density of 10 mA cm-2 and an overpotential of 445.1 mV. Subsequent testing conducted at -37°C, the temperature of Mars, has substantiated the catalyst's consistent production of oxygen without observable degradation.
Remarkably, the AI chemist accomplished the intricate catalyst optimization in a mere two months, a feat that would necessitate a human chemist approximately 2,000 years to achieve.
The team is actively striving to transform chemical AI into a comprehensive experimentation platform capable of executing diverse chemical syntheses autonomously. The article's reviewer notes that "this research holds significant interest and is rapidly advancing in the synthesis and discovery of organic/inorganic materials." JIANG envisions a future where humans can establish an oxygen factory on Mars with the assistance of chemical AI. He highlights that a mere 15 hours of solar irradiation would be adequate to generate a sufficient oxygen concentration for human survival. This technological breakthrough represents a significant stride toward realizing the aspiration of inhabiting Mars, bringing us one step closer to this ambitious goal.