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In this manuscript, we describe the fabrication of photoactive biocidal or sporicidal films from urea-derived graphitic carbon nitride (u-g-C3N4). Co-deposited films of u-g-C3N4 and Escherichia coli O157:H7 (IC50 = 14.1 ± 0.2 mJ) or Staphylococcus aureus (methicillin resistant IC50 = 33.5 ± 0.2 mJ, methicillin sensitive IC50 = 42.7 ± 0.5 mJ) demonstrated significantly enhanced bactericidal behavior upon administration of visible radiation (400 nm ≤ λ ≤ 426 nm). In all cases, complete eradication of the microbial sample was realized upon administration of 100 mJ of visible radiation, while no antimicrobial activity was observed for non-irradiated samples. In contrast, Bacillus anthracis endospores were more resistant to u-g-C3N4 mediated killing with only a ca. 25% reduction in spore viability when treated with a 200 mJ dose of visible radiation. Characterization of u-g-C3N4 reveals that the improved activity results from enhancements of both the surface area and reduction potential of the material’s conduction band edge, coupled with fast injection of charge carriers into localized states and a decline in radiative recombination events. The results of this study demonstrate that g-C3N4-based materials offer a viable scaffold for the development of new, visible light driven technologies for controlling potentially pathogenic microorganisms.

We report, for the first time, highly crystalline cyanurate-linked covalent organic frameworks synthesized via dynamic nucleophilic aromatic substitution. The high crystallinity is enabled by the bond exchange reaction (self-correction) between 2,4,6triphenoxy-1,3,5-triazine and diphenols via reversible S N Ar catalyzed by triazabicyclodecene. The CN-COFs contain flexible backbones that exhibit a unique AA′-stacking due to interlayer hydrogen bonding interactions. The isoreticular expansion study demonstrates the general applicability of this synthetic method. The resulting CN-COFs exhibited good stability, as well as high CO 2 /N 2 selectivity.

Single-ion conducting polymer electrolytes have attracted great attention as safe alternatives of liquid 11 electrolytes in high energy density lithium ion batteries. Herein, we report the first example of a crystalline 12 anionic helical polymer as a single lithium-ion conducting solid polymer electrolyte. Single crystal X-ray analysis 13shows that the polymer folds into densely packed double helices, with bundles of unidirectional negatively 14 charged channels formed that can facilitate lithium ion transportation. Such helical covalent polymer (HCP) 15 exhibits excellent room temperature lithium-ion conductivity (1.2 × 10 -3 S•cm -1 ) in the absence of external 16 lithium salts, high transference number (0.84), low activation energy (0.14 eV), and a wide electrochemical 17 stability window (0.2−5 V). We found that non-flammable, non-volatile ionic liquid can serve as a solvating 18 medium and excellent conductivity enhancer (>1000 times increase). These ion conducting properties are 19 comparable to the best polyethylene oxide-based polymer electrolytes mixed with lithium salts. Lastly, we show 20 that the solvated HCP solid polymer electrolyte enables the reversible cycling of an all-solid-state cell prepared 21

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Metal-organic frameworks (MOFs) have attracted increasing interest for broad applications in catalysis and gas separation due to their high porosity. However, the insulating feature and the limited active sites hindered MOFs as photocathode active materials for application in photoelectrocatalytic hydrogen generation. Herein, we develop a layered conductive twodimensional conjugated MOF (2D c-MOF) comprising sp-carbon active sites based on arylene-ethynylene macrocycle ligand via CuO 4 linking, named as Cu 3 HHAE 2 . This sp-carbon 2D c-MOF displays apparent semiconducting behavior and broad light absorption till the near-infrared band (1600 nm). Due to the abundant acetylene units, the Cu 3 HHAE 2 could act as the first case of MOF photocathode for photoelectrochemical (PEC) hydrogen generation and presents a record hydrogen-evolution photocurrent density of � 260 μA cm À 2 at 0 V vs. reversible hydrogen electrode among the structurally-defined cocatalyst-free organic photocathodes.

Self-sorting is commonly observed in complex reaction systems, which has been utilized to guide the formation of single major by-design molecules. However, most studies have been focused on non-covalent systems, and using self-sorting to achieve covalently bonded architectures is still relatively less explored. Herein, we first demonstrated the dynamic nature of spiroborate linkage and systematically studied the selfsorting behavior observed in the transformation between spiroborate-linked well-defined polymeric and molecular architectures, which is enabled by spiroborate bond exchange. The scrambling between a macrocycle and a 1D helical covalent polymer led to the formation of a molecular cage, whose structures are all unambiguously elucidated by single-crystal X-ray diffraction. The results indicate that the molecular cage is the thermodynamically favored product in this multi-component reaction system. This work represents the first example of a 1D polymeric architecture transforming into a shape-persistent molecular cage, driven by dynamic covalent self-sorting. This study will further guide the design of spiroborate-based materials and open the possibilities for the development of novel complex yet responsive dynamic covalent molecular or polymeric systems.

The design and development of intricate artificial architectures have been pursued for decades. Helical covalent polymer (HCP) was recently reported as an unexpected topology that consists of chiral 1D polymers assembled through weak hydrogen bonds from achiral building blocks. However, many questions remained about the formation, driving force, and the single-handedness observed in each crystal. In this work, we reveal a metastable, racemic, fully covalently cross-linked, 3D covalent organic framework (COF) as an intermediate in the early stage of polymerization, which slowly converts into single-handed HCP double helices through partial fragmentation and self-sorting with the aid of a series of hydrogen bonding. Our work provides an intriguing example where weak noncovalent bonds serve as the determining factor of the overall product structure and facilitate the formation of a sophisticated polymeric architecture.