| Texto completo | |
| Autor(es): Mostrar menos - |
Roy, Soumyabrata
;
Li, Zhengyuan
;
Chen, Zhiwen
;
Mata, Astrid Campos
;
Kumar, Pawan
;
Sarma, Saurav Ch.
;
Teixeira, Ivo F.
;
Silva, Ingrid F.
;
Gao, Guanhui
;
Tarakina, Nadezda V.
;
Kibria, Md Golam
;
Singh, Chandra Veer
;
Wu, Jingjie
;
Ajayan, Pulickel M.
Número total de Autores: 14
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Advanced Materials; v. 36, n. 13, p. 13-pg., 2024-01-06. |
| Resumo | |
Renewable-electricity-powered carbon dioxide (CO2) reduction (eCO(2)R) to high-value fuels like methane (CH4) holds the potential to close the carbon cycle at meaningful scales. However, this kinetically staggered 8-electron multistep reduction suffers from inadequate catalytic efficiency and current density. Atomic Cu-structures can boost eCO(2)R-to-CH4 selectivity due to enhanced intermediate binding energies (BEs) resulting from favorably shifted d-band centers. In this work, 2D carbon nitride (CN) matrices, viz. Na-polyheptazine (PHI) and Li-polytriazine imides (PTI), are exploited to host Cu-N-2 type single-atom sites with high density (approximate to 1.5 at%), via a facile metal-ion exchange process. Optimized Cu loading in nanocrystalline Cu-PTI maximizes eCO(2)R-to-CH4 performance with Faradaic efficiency (FECH4) of approximate to 68% and a high partial current density of 348 mA cm(-2) at -0.84 V vs reversible hydrogen electrode (RHE), surpassing the state-of-the-art catalysts. Multi-Cu substituted N-appended nanopores in the CN frameworks yield thermodynamically stable quasi-dual/triple sites with large interatomic distances dictated by the pore dimensions. First-principles calculations elucidate the relative Cu-CN cooperative effects between the matrices and how the Cu local environment dictates the adsorbate BEs, density of states, and CO2-to-CH4 energy profile landscape. The 9N pores in Cu-PTI yield cooperative Cu-Cu sites that synergistically enhance the kinetics of the rate-limiting steps in the eCO(2)R-to-CH4 pathway. (AU) | |
| Processo FAPESP: | 21/12394-0 - Métodos sintéticos sustentáveis empregando catálise, solventes verdes, reagentes seguros e materiais de partida renováveis |
| Beneficiário: | Arlene Gonçalves Corrêa |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 21/11162-8 - EMU concedido no processo 2020/14741-6: GC-MS/FID/TCD (2 injetores+Loop+Sistema valvulado) |
| Beneficiário: | Ivo Freitas Teixeira |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Equipamentos Multiusuários |
| Processo FAPESP: | 20/14741-6 - Nitretos de carbono grafítico como plataformas para single-atom fotocatálise: usando princípios de design para melhores desempenhos |
| Beneficiário: | Ivo Freitas Teixeira |
| Modalidade de apoio: | Auxílio à Pesquisa - Jovens Pesquisadores |