Luis Ruiz
Northwestern University
SelectivityChemical physicsComposite materialNanotechnologyChemistryNanostructureMaterials scienceDeformation mechanismSelf-assemblyNanotubePeptide NanotubesSoft materialsGrapheneStackingPolymerMolecular dynamicsMicrostructureNanocompositeSupramolecular chemistryToughness
17Publications
9H-index
488Citations
Publications 16
Newest
#1Zhaoxu Meng (NU: Northwestern University)H-Index: 13
#2Rafael A. Soler-Crespo (NU: Northwestern University)H-Index: 8
Last. Sinan Keten (NU: Northwestern University)H-Index: 34
view all 7 authors...
Abstract Graphene oxide (GO) shows promise as a nanocomposite building block due to its exceptional mechanical properties. While atomistic simulations have become central to investigating its mechanical properties, the method remains prohibitively expensive for large deformations and mesoscale failure mechanisms. To overcome this, we establish a coarse-grained (CG) model that captures key mechanical and interfacial properties, and the non-homogeneous effect of oxidation in GO sheets. The CG mode...
33 CitationsSource
#1Wenjie Xia (NU: Northwestern University)H-Index: 20
#2Luis Ruiz (NU: Northwestern University)H-Index: 9
Last. Sinan Keten (NU: Northwestern University)H-Index: 34
view all 4 authors...
Multi-layer graphene assemblies (MLGs) or fibers with a staggered architecture exhibit high toughness and failure strain that surpass those of the constituent single sheets. However, how the architectural parameters such as the sheet overlap length affect these mechanical properties remains unknown due in part to the limitations of mechanical continuum models. By exploring the mechanics of MLG assemblies under tensile deformation using our established coarse-grained molecular modeling framework,...
40 CitationsSource
#1Xiaoding Wei (NU: Northwestern University)H-Index: 24
#2Zhaoxu Meng (NU: Northwestern University)H-Index: 13
Last. Horacio D. Espinosa (NU: Northwestern University)H-Index: 75
view all 9 authors...
Understanding the deformation mechanisms in multilayer graphene (MLG), an attractive material used in nanodevices as well as in the reinforcement of nanocomposites, is critical yet challenging due to difficulties in experimental characterization and the spatiotemporal limitations of atomistic modeling. In this study, we combine nanomechanical experiments with coarse-grained molecular dynamics (CG-MD) simulations to elucidate the mechanisms of deformation and failure of MLG sheets. Elastic proper...
64 CitationsSource
#1Luis Ruiz (NU: Northwestern University)H-Index: 9
#2Ari S. Benjamin (NU: Northwestern University)H-Index: 9
Last. Sinan Keten (NU: Northwestern University)H-Index: 34
view all 4 authors...
We use atomistic nonequilibrium molecular dynamics simulations to demonstrate how specific ionic flux in peptide nanotubes can be regulated by tailoring the lumen chemistry through single amino acid substitutions. By varying the size and polarity of the functional group inserted into the nanotube interior, we are able to adjust the Na+ flux by over an order of magnitude. Cl− is consistently denied passage. Bulky, nonpolar groups encourage interactions between the Na+ and the peptide backbone car...
9 CitationsSource
#1Luis Ruiz (NU: Northwestern University)H-Index: 9
#2Wenjie Xia (NU: Northwestern University)H-Index: 20
Last. Sinan Keten (NU: Northwestern University)H-Index: 34
view all 4 authors...
Abstract Graphene is the strongest and highest weight-to-surface ratio material known, rendering it an excellent building block for nanocomposites. Multi-layer graphene (MLG) assemblies have intriguing mechanical properties distinct from the monolayer that remain poorly understood due to spatiotemporal limitations of experimental observations and atomistic modeling. To address this issue, here we establish a coarse-grained molecular dynamics (CG-MD) model of graphene using a strain energy conser...
97 CitationsSource
#1Luis Ruiz (NU: Northwestern University)H-Index: 9
#2Yuanqiao Wu (NU: Northwestern University)H-Index: 1
Last. Sinan Keten (NU: Northwestern University)H-Index: 34
view all 3 authors...
Self-assembly of cyclic peptide nanotubes (CPNs) in polymer thin films has opened up the possibility of creating separation membranes with tunable nanopores that can differentiate molecules at the sub-nanometer level. While it has been demonstrated that the interior chemistry of the CPNs can be tailored by inserting functional groups in the nanopore lumen (mCPNs), a design strategy for picking the chemical modifications that lead to particular transport properties has not been established. Drawi...
35 CitationsSource
#1Luis Ruiz (NU: Northwestern University)H-Index: 9
#2Sinan Keten (NU: Northwestern University)H-Index: 34
We report classical and replica exchange molecular dynamics simulations that establish the mechanisms underpinning the growth kinetics of a binary mix of nanorings that form striped nanotubes via self-assembly. A step-growth coalescence model captures the growth process of the nanotubes, which suggests that high aspect ratio nanostructures can grow by obeying the universal laws of self-similar coarsening, contrary to systems that grow through nucleation and elongation. Notably, striped patterns ...
4 CitationsSource
#1Luis Ruiz (NU: Northwestern University)H-Index: 9
#2Sinan Keten (NU: Northwestern University)H-Index: 34
AbstractCyclic peptide nanotubes (CPNs) have unique chemical and mechanical features that squarely position them to tackle persistent challenges in sensor technologies, tissue scaffolds, templates for organic and hybrid electronics, and ultrasmall electromechanical systems. These self-assembled hierarchical nanostructures are highly organized at the nanoscale and feature exceptional thermodynamical stability arising from the collective action of secondary interactions, in particular intersubunit...
8 CitationsSource
#1Robert Sinko (NU: Northwestern University)H-Index: 11
#2Shawn Mishra (NU: Northwestern University)H-Index: 8
Last. Sinan Keten (NU: Northwestern University)H-Index: 34
view all 5 authors...
Cellulose nanocrystals (CNCs) exhibit outstanding mechanical properties exceeding that of Kevlar, serving as reinforcing domains in nature’s toughest biological nanocomposites such as wood. To establish a molecular-level understanding of how CNCs develop high resistance to failure, here we present new analyses based on atomistic simulations on the fracture energy of Iβ CNCs. We show that the fracture energy depends on the crystal width, due to edge defects that significantly reduce the fracture ...
51 CitationsSource