Graphene Nanoribbon/Carbon Nanotube Hybrid Hydrogel: Rheology and Membrane for Ultrafast Molecular Diafiltration
Ju Yeon Kim, Yunkyu Choi, Jiho Choi, Yong-Jae Kim, Junhyeok Kang, Jeong Pil Kim, Ji Hoon Kim, Ohchan Kwon, Sung‐Soo Kim, Dae Woo Kim
Abstract
Hybrids based on carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) are expected to have synergistic effects for various applications. Herein, we demonstrate a simple one-pot synthesis of a CNT/GNR hybrid material by adjusting the oxidation and unzipping conditions of multi-walled CNTs (MWNTs). The MWNT/graphene oxide nanoribbon (GONR) hybrid was dispersed in various solvents, particularly showing the hybrid hydrogel phase in water at a concentration of 40 mg mL–1. The MWNT/GONR hydrogel exhibited shear-thinning behavior, which can be beneficial for coating a large-area MWNT/GONR layer onto a polymeric porous support by using a scalable slot-die coater. The MWNT/GONR membrane exhibited an outstanding nanofiltration performance, with a molecular weight cutoff of 300 Da and a dye/salt diafiltration performance with a separation factor of 1000 and a water flux of 367.8 LMH, far surpassing the upper bound of diafiltration performance of the existing membranes.