Carbon-in-Al₄C₃ Nanowire Superstructures for Field Emitters

Abstract

As a kind of ionic (or salt-like) carbide, for Al(4)C(3), hardly any active functions have been found except for structure material purposes. However, considering the unique characteristic features of its crystal structure, we think Al(4)C(3) in fact might have huge potential for exhibiting active functionality on field-emission applications. Herein, we report the feasibility to approach such emitters by creating Al(4)C(3)-based nanowire superstructures. The conductive amorphous carbon (a-C) nanolayers are embedded quasi-periodically in Al(4)C(3) nanowire and generate essential electrical contact to the insulating Al(4)C(3). The superstructures acting as cold electron emitters display excellent field emission performance with the turn-on field as low as 0.65-1.3 V/μm and the threshold field down to 2.1-2.6 V/μm. We speculate that the emission characteristics, which are ever better than carbon nanotubes, are attributed to the unique crystal structure of Al(4)C(3) and the enhanced electrons transport in the nanowires due to the existence of a-C nanolayers. Such emitters are technologically useful, because they can be easily fabricated on large substrates, and the synthesis process is simple and broadly applicable. The findings conceptually provide new opportunities for the application of Al(4)C(3) ceramic material in vacuum microelectronic devices.

Rapid, energy-efficient synthesis of the layered carbide, Al4C3

“…The spectrum is comprised of six bands, which correspond closely to those reported previously. 5,6 There is no evidence of bands from carbon in the recorded spectra; bands for disordered (D) and ordered (graphitic; G) carbon would be expected at 1350 cm -1 and 1590 cm -1 for respectively. 29 Further, there are no bands for other Al-containing species such as the various polymorphs of Al2O3 30 and hence Raman spectroscopy would support diffraction evidence that the only product of the microwave reactions is Al4C3.…”

“…Up to the present time, only a small number of reports referring to the synthesis and application of the phase have been published. [1][2][3][4][5][6] Al4C3 has a layered rhombohedral structure (R3 ̅ m) composed of alternating Al2C and Al2C2 layers. 7 Aluminium carbide often arises as an undesired degradation product which can have a significant negative impact on SiC-Al and carbon-fibre composites.…”

Three dimensional self-assembly ZnSb nanowire balls with good performance as sodium ions battery anode

“…Herein, a Small amount of C 60 powder was employed as assistant precursor. Benefiting from the low sublimation temperature ($350 C) and large ball-shape molecule, C 60 does well in consuming residue oxygen at this temperatures range [22], while H 2 and common carbon are incapable. Importantly, C 60 is nonreactive with Zn and Sb species.…”

Synthesis and field-emission properties of novel hierarchical ZnO hexagonal towers

“…Hierarchical-structure ZnO [11] 4.8 3400 ZnO nanotubes [13] 3.5 Hierarchical ˇ-SiC nanoarchitectures [5] 12 CNT [19] 3.87 1737 Carbon-in-Al4C3 nanowire [7] 0.65-1.3 2.3-2.6 ZnS tetra pod tree-like heterostructures [6] 2.66 2600…”

“…[3]. Many reports were focused on the development of nanostructures with different morphology or shape, such as ZnS branched architectures [4], hierarchical single-crystalline ˇ-SiC nanoarchitectures [5], ZnS tetrapod tree-like heterostructures [6], carbon-in-Al 4 C 3 nanowires [7] and sixfold-symmetrical hierarchical ZnO [8].…”