S. Zhang, W. Zhou, J. Chen, B. Harris, M. Baer, C.L. Chen, J. DeYoreo
Pacific Northwest National Laboratory,
United States
Keywords: biopolymer, van der Waas materials, multi-phase assembly
Summary:
Biopolymer assembly has emerged as a pivotal strategy in synthesizing biohybrid materials with wide-ranging applications. Recently, there has been a growing interest in assembling biopolymers, including proteins and peptides, on van der Waals (vdW) materials for bioelectronics, including sensors, memristor, force generator, etc. However, a comprehensive understanding of the hierarchical assembly of these biomolecules on vdW surfaces remains incomplete. Challenges persist in modulating assembly architectures through environmental stimuli and navigating the energy landscape governing various assembly phases. In addition, the principle of achieving desirable electronic properties with programmable biopolymer assembly on vdW surface is also unknown. In recent years, our research has focused on designing a series of biopolymers, encompassing peptides and peptoids, tailored for controllable hierarchical assemblies on vdW surfaces such as graphene, MoS2, and WS2. In this discussion, I will emphasize two short peptoid sequences with assembly capabilities on MoS2. Our investigations have revealed diverse phases of peptoid assembly on MoS2, including monolayer hybrid films with high crystallinity, vesicles, lamella, and multi-layer ribbons. Moreover, we have elucidated the assembly processes of these different states and confirmed their phase transitions. Critical to these processes are the interactions between peptoids, solvents, and MoS2, which are mediated by factors such as pH. These interactions play crucial roles in driving hierarchical assembly and can also modulate the surface potential of vdW materials. Our findings contribute significantly to advancing the understanding of designing hierarchical architectures with biomolecules at vdW-solvent interfaces, offering promising opportunities to optimize the performance of biopolymer-2D vdW materials for applications in energy transfer and quantum information processing.