Heterogeneous integrations of functionally and chemically distinct materials have been explored to develop promising building blocks for opto‐electronic device applications. Recently, the Van der Waals (vdW)‐assembly of near atom thickness materials has provided excellent opportunities beyond what has been previously been difficult to realize. However, its up‐to‐date demonstrations remain far from achieving the scalability and versatility demanded for practical device applications, that is, the integration is generally demonstrated with intrinsically layered 2D materials of very small lateral dimensions. Herein, the large centimeter‐scale vdW assembly of two different materials with structurally, chemically, and functionally distinct properties, that is, 2D platinum ditelluride (PtTe2) metallic multilayers and non‐layered 3D semiconducting platinum sulfide (PtS) are reported. Both materials are precisely delaminated from their growth wafers inside water and are subsequently integrated on unconventional substrates of desired functionalities. The large‐area vdW‐assembled 2D/3D PtTe2/PtS hetero‐materials on flexible substrates exhibit an excellent photodetection in a spectral range of visible‐to‐near infrared (NIR) wavelength, which is well preserved under severe mechanical deformation. This study paves the way for exploring large‐area flexible opto‐electronic devices solely based on near atom thickness materials.
Vertically aligned nanocomposites (VAN) thin films present as an intriguing material family for achieving novel functionalities. However, most of the VAN structures tend to grow in a random fashion, hindering the future integration in nanoscale devices. Previous efforts for achieving ordered nanopillar structures have been focused on specific systems, and rely on sophisticated lithography and seeding techniques, making large area ordering quite difficult. In this work, a new technique is presented to produce self‐assembled nanocomposites with long‐range ordering through selective nucleation of nanocomposites on termination patterned substrates. Specifically, SrTiO3(001) substrates have been annealed to achieve alternating chemical terminations and thus enable selective epitaxy during the VAN growth. La0.7Sr0.3MnO3:CeO2(LSMO):CeO2nanocomposites, as a prototype, are demonstrated to form well‐ordered rows in matrix structure, with CeO2(011) domains selectively grown on SrO terminated area, showing enhanced functionality. This approach provides a large degree of long‐range ordering for nanocomposite growth that could lead to unique functionalities and takes the nanocomposites one step closer toward future nanoscale device integration.
more » « less- NSF-PAR ID:
- 10033792
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 29
- Issue:
- 23
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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