resumo
A high-throughput analysis based on density functional simulations underscores the viable epitaxial growth of MXenes by alternating nitrogen and metal adlayers. This is supported by an exhaustive analysis of a number of thermodynamic and kinetic thresholds belonging to different critical key steps in the course of the epitaxial growth. The results on 18 pristine N-and C-based MXenes with M2X stoichiometry reveal an easy initial N-2 fixation and dissociation, where N-2 adsorption is controlled by the MXene surface charge and metal d-band center and its dissociation controlled by the reaction energy change. Furthermore, formation energies indicate the plausible formation of N-2-terminated M2XN2 MXenes. Moreover, the further covering with metal adlayers is found to be thermodynamically driven and stable, especially when using early transition metal atoms. The most restrictive analyzed criterion is the N2 adsorption and dissociation at nearly full N-covered adlayers, which is yet achievable for almost half of the explored M2X seeds. The present results unfold the possibility of expanding, controlling, and tuning the composition, width, and structure of the MXene family.
palavras-chave
FINDING SADDLE-POINTS; MAX-PHASE; CARBIDE; SURFACES
categoria
Chemistry; Science & Technology - Other Topics; Materials Science
autores
Gouveia, JD; Morales-Garcia, A; Vines, F; Gomes, JRB; Illas, F
nossos autores
José Daniel Lago da Silva Neves Gouveia
Investigador Auxiliar
José R. B. Gomes
Investigador PrincipalProjectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
Modeling the synthesis of SILica materials VIA multiscale computer simulations (SILVIA)
agradecimentos
The work carried out at the Universitat de Barcelona has been supported by the Spanish MCIN/AEI/10.13039/501100011033 RTI2018-095460-B-I00 (funded partially from FEDER Una manera de hacer Europa) and Maria de Maeztu MDM-2017-0767 project, and the work carried out at CICECO-Aveiro Institute of Materials has been financed through projects UIDB/50011/2020, UIDP/50011/2020, and LA/P/0006/2020, financed by national funds through the Fundacao para a Ciencia e a Tecnologia (FCT/MCTES) and cofinanced by FEDER under the PT2020 Partnership Agreement. A.M.-G. thanks the support by the PID2020- 115293RJ-I00 project funded by MCIN/AEI/10.13039/501100011033, and J.D.G. thanks project SILVIA with references CENTRO-01-0145-FEDER-31002 and PTDC/QUI-QFI/31002/2017. We are also thankful to FCT I.P. for the computational resources granted in the framework of project EPICNITRO (ref. CPCA/A2/6817/2020) by the FCT/CPCA/2020/01 Call for Advanced Computing Projects.