Nanoporous Metals: From Plasmonic Properties to Applications in Enhanced Spectroscopy and Photocatalysis

Abstract

The field of plasmonics is capable of enabling interesting applications in different wavelength ranges, spanning from the ultraviolet up to the infrared. The choice of plasmonic material and how the material is nanostructured has significant implications for ultimate performance of any plasmonic device. Artificially designed nanoporous metals (NPMs) have interesting material properties including large specific surface area, distinctive optical properties, high electrical conductivity, and reduced stiffness, implying their potentials for many applications. This paper reviews the wide range of available nanoporous metals (such as Au, Ag, Cu, Al, Mg, and Pt), mainly focusing on their properties as plasmonic materials. While extensive reports on the use and characterization of NPMs exist, a detailed discussion on their connection with surface plasmons and enhanced spectroscopies as well as photocatalysis is missing. Here, we report on different metals investigated, from the most used nanoporous gold to mixed metal compounds, and discuss each of these plasmonic materials’ suitability for a range of structural design and applications. Finally, we discuss the potentials and limitations of the traditional and alternative plasmonic materials for applications in enhanced spectroscopy and photocatalysis.

Effects of Pore Connectivity on the Sorption of Fluids in Nanoporous Material: Ethane and CO2 Sorption in Silicalite

“…For example, it is possible to control the microstructure and pore sizes in nanoporous metals by controlling the conditions and strategies of synthesis [26]. Results presented above suggest that this control can be used to enhance the sorption capabilities of such nanoporous materials in addition to providing a way of controlling nanofluidic transport [27].…”

Surface Plasmonic Sensors: Sensing Mechanism and Recent Applications

“…Later, Shen et al [ 131 ] reported a relative humidity (RH) sensors based on this hybrid mode platform, which exhibited wavelength sensitivity of 1.16 nm %RH and a quick response time of a few seconds. Besides the ordered plasmonic nanostructures mentioned above, the disordered system without delicate design of structures is also promising for sensors with the advantages of low-cost and simple excitation schemes [ 132 ]. This system with rough surface can also increase the FOM through Fano-resonant transmission profile [ 133 ].…”

A Scalable Solution Route to Porous Networks of Nanostructured Black Tungsten

“…One growing use of W is as a high-temperature, absorber layer to increase the solar absorptivity and decrease the thermal emissivity of solar thermal collectors or receivers for various energy applications [ 1 , 5 , 6 , 7 ]. Particularly, creating plasmonic nanostructured metals (nanorods, nanoparticles, nanoporous films) is of great interest as they augment the absorption of electromagnetic radiation over a tunable range of UV to near IR [ 8 , 9 ]. Different synthesis methods have been used to manufacture W films and coatings capable of modifying the solar absorptance of these surfaces.…”