 This paper discusses the development of a new type of porous adsorbent in H4, plus COF-03 dash, which has been shown to have exceptional properties for the selective adsorption of uranium from seawater. The adsorbent was found to be capable of achieving a uranium adsorption capacity of 17.8 mg per G, which is significantly higher than other known porous materials. Additionally, the adsorbent demonstrated excellent stability when exposed to harsh conditions such as pH levels of 1, 8, and 3, indicating its potential use in applications where extreme conditions are present. This article was authored by Xiaohong Xiong, Xiwu Yu, Lila Gong, and others.