Oil is the black gold of the modern world.
Plastic, nylon, fertilizer, dye, medicine, a lot of important products are made
from oil. The modern chemical industry uses a top-down method to produce these
products: shorten the long carbon chain molecules in the oil and turn them into
materials with shorter carbon chains. This process is accompanied by a large
amount of carbon emissions and fossil fuel consumption. Haotian Wang, an
assistant professor at Rice University, has developed a revolutionary method to
produce ethylene, formic acid, ethanol, and other valuable chemicals from the
bottom-up. He uses “unwanted” carbon dioxide as the raw material and renewable
electricity as the energy input. This green, sustainable, and economical
process reduces the carbon dioxide level in the atmosphere and obtains green
chemical products at the same time.
The challenge of this technology is the
lack of highly active and selective catalysts. To solve the problem, Haotian reduced
the size of the catalyst to atomic-scale and developed a game-changing “single
atom catalyst” with record-high activity and selectivity (99%). With it, they
built an artificial-photosynthesis system with a breakthrough solar-to-fuel conversion
efficiency of 12.7%, which is orders of magnitudes higher than natural
photosynthesis in green plants. They also developed a solid-state electrolyte
technology to produce high purity liquid chemical products which can be
directly put into use without separation or purification. At present, they are working
together with the industry to realize the electrochemical production of a
series of chemical products such as hydrogen peroxide, ethanol, formic acid, and
acetic acid. They hope to apply them on large scale energy storage, chemical
production, and waste-water treatment. If successful, this new concept of
"green chemical engineering" will be a clean revolution for the
chemical industry.