Catalytic role of biochar surface groups in phenol formation from lignin pyrolysis: Experimental and DFT insights - Ding Jiang; Hongping Li; Xiaoxue Cheng; Pietro Bartocci; Arman Amani Babadi; Minggao Xu; Yang Pan; Bin Cao; Osvalda Senneca; Shuang Wang (Chemical Engineering Journal, 2025)