Moon also instructed government officials on Wednesday to quicken the retirement of old coal-burning power plants, according to his spokesman, Kim Eui-kyeom.
When asked about Moon's proposal, Chinese foreign ministry spokesman Lu Kang said cooperation would be good but downplayed Seoul's claim that China is a major source of its pollution.
"I wonder if the South Korean side has any basis that its smog is from China," Lu said, noting that fine dust readings have been higher in Seoul than in Beijing recently. "All countries realize that the cause is very complicated."
As of 4 p.m. Wednesday, the fine dust concentration level was 136 micrograms per cubic meter in Seoul, according to the National Institute of Environmental Research, which defines levels above 75 micrograms per cubic meter as "very bad."
Na Kyung-won, the floor leader of the conservative Liberty Korea Party, called for Moon to designate the air pollution as a national disaster. Ruling and opposition parties held an emergency meeting at which they agreed to swiftly pass bills to cope with the problem.
In a meeting with government officials, Moon noted that China was "much more advanced" than South Korea in rain-making technologies and expressed hope that creating rain over waters between the countries would help mitigate the air pollution, Kim said.
In January, South Korea's weather agency failed in an experiment to create artificial rain which involved an aircraft releasing chemicals into clouds over the sea.
"China has claimed that South Korea's dust flies toward Shanghai, so creating artificial rain over the Yellow Sea would help the Chinese side too," Kim quoted Moon as saying during the meeting. Moon also proposed that South Korea and China develop a joint system for issuing air pollution alerts, Kim said.
Moon instructed government officials to take steps to quickly close coal-burning power plants that have operated for more than 30 years and draw up an extra budget if necessary to install more air purifiers in schools and support possible joint activities with China, Kim said.
In a meeting with top Chinese diplomat Yang Jiechi last year, Moon said China was partially responsible for South Korea's pollution problem and called for Beijing's cooperation in efforts to improve air quality.
AP researcher Liu Zheng in Beijing contributed to this report.