N-Doped MoS<sub>2</sub> Nanoflowers for Efficient Cr(VI) Removal
Fan‐Yi Meng, Hao Wu, Meng Qiao, Xiaofei Zeng, Dan Wang, Jie‐Xin Wang
Abstract
The removal of Cr(VI) has attracted extensive attention since it causes serious harm to public health. Herein, we report a two-step method to synthesize N-doped MoS2 nanoflowers (NFs) with controllable sizes, which are first utilized for Cr(VI) removal and display outstanding removal performance. The N-MoS2 NFs with an average size of 40 nm (N-MoS2 NFs-40 nm) can rapidly remove Cr(VI) in 15 min under optimal conditions. The maximum adsorption capacity of N-MoS2 NFs-40 nm can reach 787.41 mg·g–1, which is significantly larger than that of N-MoS2 NFs-150 and -400 nm (314.46 and 229.88 mg·g–1). Meanwhile, N-MoS2 NFs-400 nm have a higher maximum adsorption capacity than pure MoS2 NFs-400 nm (172.12 mg·g–1). In this adsorption/reduction process, N-MoS2 NFs have abundant adsorption sites due to a high surface area. N doping can generate more sulfur vacancy defects in the MoS2 NF structure to accelerate electron transfer and enhance the reduction of Cr(VI) to low-toxicity Cr(III). This study provides a facile approach to fabricating N-MoS2 nanoflowers and demonstrates their superior removal ability for Cr(VI).