We demonstrate large-area conductive polymer films using oxidative chemical vapor deposition and apply them to low-cost and durable conductive textiles.

Membranes possessing high permeability to water vapor and high liquid entry pressure (LEP) are necessary for efficient membrane distillation (MD) desalination. A common technique to prepare specialized MD membranes consists of coating a hydrophilic or hydrophobic base membrane with a low surface-energy material. This increases its liquid entry pressure, making the membrane suitable for MD. However, in addition to increasing LEP, the surface-coating may also decrease permeability of the membrane by reducing its average pore size. In this study, we quantify the effects of initiated chemical vapor deposition (iCVD) polymer coatings on membrane permeability and LEP. We consider whether the iCVD films should have minimized thickness or maximized non-conformality, in order to maximize the permeability achieved for a given value of LEP. We determined theoretically that permeability of a single pore is maximized with a highly non-conformal iCVD coating. However, the overall permeability of a membrane consisting of many pores is maximized when iCVD film thickness is minimized. We applied the findings experimentally, preparing an iCVD-treated track-etched polycarbonate (PCTE) membrane and testing it in a permeate gap membrane distillation (PCMD) system. This study focuses on membranes with clearly defined, cylindrical pores. However, we believe that the principles we discuss will extend to membranes with more complex pore architectures. Overall, this work indicates that the focus of surface-coating development should be on minimizing film thickness, not on increasing their non-conformality. Keywords: Membrane distillation (MD), Desalination, Track-etched polycarbonate (PCTE) membranes, Dusty gas model, Initiated chemical vapor deposition (iCVD). SLStep coverage of the iCVD coating, can be written as = S(x)Step coverage of the iCVD coating within the membrane, written as =

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We are deeply grateful to the mentorship and friendship of Professor Nadrian C. Seeman, who passed away during the writing of this manuscript, and whose foundational work and guidance to DNA Nanotechnology was a light to all DNA double helices containing metal-mediated DNA (mmDNA) base pairs are constructed from Ag + and Hg 2+ ions between pyrimidine:pyrimidine pairs with the promise of nanoelectronics. Rational design of mmDNA nanomaterials is impractical without a complete lexical and structural description. Here, the programmability of structural DNA nanotechnology toward its founding mission of self-assembling a diffraction platform for biomolecular structure determination is explored. The tensegrity triangle is employed to build a comprehensive structural library of mmDNA pairs via X-ray diffraction and generalized design rules for mmDNA construction are elucidated. Two binding modes are uncovered: N3-dominant, centrosymmetric pairs and major groove binders driven by 5-position ring modifications. Energy gap calculations show additional levels in the lowest unoccupied molecular orbitals (LUMO) of mmDNA structures, rendering them attractive molecular electronic candidates.