Tunable nanoarchitectonics of porous biochar through sequential calcium and potassium salt activation for high-efficiency removal of emerging pollutants - Yajing Liu; Ziqi Shen; Yijia Huangliang; Rongting Ji; Honghua Ruan; Yang Song; Jianming Xue; Fuliang Cao; Sicheng Shao; Hu Cheng (Bioresource Technology, 2026)