Yun Yu, Ning Qiao, Danjun Wang, Qizhen Zhu, Feng Fu, Ruiqi Cao, Ran Wang, Wei Liu, Bin Xu*

Fluffy honeycomb-like activated carbon with ultra-high surface area and well-developed hierarchical porousstructure is simply prepared from popcorn by NaOH activation as adsorbent for dye removal. The popcorn has anunique fluffy structure, which originates from the corn via a rapid puffing process and is reserved during the following carbonization and NaOH activation. The ultra-high surface area and developed hierarchical porousstructure make PDAC-4 show an outstanding adsorption capacity of 7765 mg·g^-1 for Rhodamine B(2500 mg·L^-1), which is several times higher than those of the adsorbents ever reported. Moreover, PDAC-4 alsohas excellent adsorption performance for other dyes, such as Congo Red, Methylene Blue and Methyl Orange.The superior adsorption performance of PDACs to organic dyes opens its potential application in the purificationof dye wastewater.