Enhancing electromagnetic shielding with cellulose-assisted screen printed graphene nanosheet films.

Graphene-based dielectric materials, known for their high conductivity, hold promise for electromagnetic shielding, yet face limitations due to production challenges. To address this, we employed homogenization and ultrasound techniques to disrupt van der Waals bonding, followed by the addition of cellulose as a barrier to inhibit particle aggregation. Graphene nanosheets were layered through screen-printing techniques. By subjecting the structure to an annealing process that carbonized the barrier, graphene nanosheets were brought into contact, establishing an electron hopping pathway. This process led to a significant surge in conductivity, jumping from 23.8 to 633.0 S/cm. Leveraging the superior conductivity induced by graphene nanosheets compaction and reduced defects, the resulting printed films, with a thickness of 15.8 μm, achieved an electromagnetic interference shielding effectiveness (EMI SE) of 30.8 dB, and with a thickness of 7.8 μm, demonstrated a high absolute shielding effectiveness (SSE/t) of 25571 dB cm2 g−1. Our findings present a viable strategy for enhancing shielding capabilities of other 2D materials such as MXenes and transition metal sulfides (TMDC) [ABSTRACT FROM AUTHOR]