Agradecimentos: The authors gratefully acknowledge the financial support from Brazilian research agencies CNPq, FAPESP, and FAP-DF. M. L. P. J gratefully acknowledges the financial support from CAPES grant 88882.383674/2019-01. L. A. R. J acknowledges the financial support from a Brazilian Research Council FAP-DF grants 00193-00000853/2021-28 and 00193-00000811/2021-97 and CNPq grant 302236/2018-0, respectively. L. A. R. J acknowledges CENAPAD-SP for providing the computational facilities. L. A. R. J. gratefully acknowledges the financial support from IFD/UnB (Edital 01/2020) grant 23106.090790/2020-86. W. F. C. acknowledges the financial support from FAPDF grant 00193-00000857/2021-14. The authors acknowledge the National Laboratory for Scientific Computing (LNCC/MCTI, Brazil) for providing HPC resources of the SDumont supercomputer, which have contributed to the research results reported within this paper. URL: http://sdumont.lncc.br.DSG acknowledges the Center for Computational Engineering and Sciences at Unicamp for financial support through the FAPESP/CEPID Grant #2013/08293-7. L. A. R. J. and R. T. S. J. gratefully acknowledge the support from ABIN grant 08/2019. R. T. S. J. gratefully acknowledges, respectively, the support from EC Horizon 2020 HEROES project grant 101021801, CNPq grants 465741/2014-2 and 312180/2019-5, CAPES grant 88887.144009/2017-00, and FAP-DF grants 0193.001366/2016 and 0193.001365/2016 Ver menos

Abstract: Recently, a new two-dimensional carbon allotrope named biphenylene network (BPN) was experimentally realized. The BPN structure consists of four-, six-, and eight-membered rings of sp(2)-hybridized carbon atoms. In this work, we carried out fully-atomistic reactive (ReaxFF) molecular dynamics simulations to study the mechanical properties and fracture patterns of non-defective and defective (nanocracks) BPN. Results show that, under uniaxial tensile loading, BPN is converted into four distinct morphologies before fracture starts. This conversion process is dependent on the stretching direction. Some of the formed structures contain mainly eight-membered rings, which have different shapes in each morphology. In one of them, a graphitization process occurs before the complete fracture. Importantly, in the presence of nanocracks, no new morphologies are formed. BPN exhibits a distinct fracture process when contrasted to graphene. After the critical strain threshold, the graphene transitions from an elastic to a brittle regime, while BPN can exhibit different inelastic stages. These stages are associated with the appearance of new morphologies. However, BPN shares some of the exceptional graphene properties. BPN Young's modulus and melting point are comparable to graphene, about 1019.4 GPa and 4024 K, respectively Ver menos