Strong and flaw-insensitive two-dimensional covalent organic frameworks

(Matter 4, 1017–1028; March 3, 2021) The authors regret that the printed version of above article contained two errors. The correct and final version are as follows. These do not affect the results, findings and conclusions. 1. Table S1 in supplementary document The first correction is that the value of fracture strength, Young’s modulus and fracture toughness of COF films in Table S1, the correct value should be 0.75 ± 0.34 GPa, 10.38 ± 3.42 GPa and 0.55 ± 0.09 MPa√m, respectively. 2. Equation (4) for the prediction of flaw-insensitivity The (4) should be expressed as follows:wc=2Kc2(1−α)2πασf2(C1) substituting σf = 0.75 GPa and Kc = 0.55 MPa√m into this equation, the minimum value wcmin of wc was estimated to be 2.30 μm. The equation was used to generate the result presented in Figure 4D. After correcting Equation (4), related discussion and the figure was fixed accordingly in main text and the theoretical prediction trend remains the same. The authors would like to thank Bo Ni, Brown University, for helpful discussions on these errors.Figure 4. In situ SEM mechanical testing for fracture toughness and behaviors of COFTAPB-DHTA films (original)View Large Image Figure ViewerDownload (PPT) Strong and flaw-insensitive two-dimensional covalent organic frameworksFang et al.MatterJanuary 28, 2021In BriefIn this paper, the tensile fracture strength, Young's modulus, and toughness of ultrathin COFTAPB-DHTA films were measured to be 0.75 GPa, 10.38 GPa, and 0.55 MPa√m, respectively, using a quantitative in situ SEM tensile mechanical testing method. In addition, a flaw-insensitive fracture behavior was observed. This work provides an in-depth understanding on the mechanical properties of 2D COF films and lays a strong foundation for their applications. Full-Text PDF Open Archive