Ultrafast Photoinduced Heat Generation by Plasmonic HfN Nanoparticles

Abstract

carrier generation. [1,2] This has led to sig nificant interest in plasmonic nanostruc tures for photocatalysis, either through local heat generation or as a photo sensitizer. [3,4] Materials in the family of plasmonic transition metal nitrides (e.g., TiN, HfN, NbN, WN) feature high ther momechanical robustness and recently have been proposed for applications requiring extreme operating conditions, such as photothermal catalysis or solar thermophoto voltaics. [5] These materials have high melting points and demonstrate high temperature durability, chemical sta bility, and corrosion resistance, while pre senting an optical response similar to Au or Ag plasmonic nanostructures. [5,6] With a strong response in the visible range, high mechanical hardness, low material cost, [6][7][8][9] and outstanding performance in electro chemical reactions, [10][11][12] the photophysics of these materials requires further research. In the following, we will briefly review the current level of understanding of the photophysics of noble metal plasmonic particles, followed by a discussion on transition metal nitride plasmonic nanoparticles.Light absorption and heat generation by noble metal nano particles can be summarized as follows: first, the local surface plasmon resonance (LSPR) is excited, which lasts several fs and decays by nonradiative dephasing through Landau damp ening (1-100 fs). This process generates hot carriers at regions with high optical absorption (hotspots), the hot carriers subse quently decay by electron-electron scattering (1-100 fs) followed by electron-phonon coupling (0.1-10 ps). Ultimately, phonons dissipate heat to the surroundings (1-10 ns). [4,13,14] There is increasing interest in hot carrier processes, chemical reac tions induced by them, and determining whether the observed changes in chemical reactions are due to lattice heating or hot charge carriers. [15,16] Since elementary chemical transformations typically occur on a 1-100 ps timescale, [17] it is essential to characterize the light induced carrier dynamics and thermal relaxation of plasmonic systems that consist of nonnoble metal materials. Recent studies have shown that in particular hafnium nitride (HfN) performs well at converting light into heat through thermoplas monic relaxation. [18,19] This efficient lightinduced heating likely stems from a less negative real permittivity (ε′) and a higher imaginary permittivity (ε″) of HfN relative to noble metals, leading to a lossy plasmonic response accompanied by lower There is great interest in the development of alternatives to noble metals for plasmonic nanostructures. Transition metal nitrides are promising due to their robust refractory properties. However, the photophysics of these nanostructures, particularly the hot carrier dynamics and photothermal response on ultrafast timescales, are not well understood. This limits their implementation in applications such as photothermal catalysis or solar thermophotovoltaics. In this study, the light-induced relaxation processes in water-dispersed Hf...

NiSe and CoSe Topological Nodal‐Line Semimetals: A Sustainable Platform for Efficient Thermoplasmonics and Solar‐Driven Photothermal Membrane Distillation

“…In general, replacing Ag and Au with cheap materials, exhibiting plasmonic resonances matching with the solar spectrum is one of the main open challenges of the whole plasmonic community. [ 23 ] Recently, several candidates for have emerged, such as nitrides (TiN [ 24 ] and HfN [ 25 ] ), SnS 2 [ 26 ] /SnSe 2 , [ 27 ] Xenes (phosphorene, [ 28 ] arsenene, [ 29 ] stanene [ 30 ] ), titanium carbides (namely, MXenes [ 31 ] ), metal oxides, [ 32 ] etc. However, most of them have poor photothermal efficacy [ 10e ] and high chemical instability with spontaneous oxidation already at room temperature, as in the case of Xenes [ 33 ] or tin dichalcogenides.…”

Transition Metal Nitrides Are Heating Up the Field of Plasmonics

“…90 Transient absorption measurements and simulations performed on HfN NPs showed conversion of absorbed photons to heat in less than 100 fs (Figure 3D), whereas it takes a few picoseconds for this process to occur in Au. 91 The calculated electron−phonon coupling constant for HfN (1.4 × 10 18 W/m 3 K) was 50 times stronger than for Au (2.8 × 10 16 W/m 3 K) and also slightly better than that for TiN ((0.8−1.0) × 10 18 W/m 3 K) and ZrN (1.0 × 10 18 W/m 3 K). The high temperature stability accompanied by fast thermalization observed in nitrides make them attractive candidates for thermoplasmonic applications.…”

Tailoring Properties of Hafnium Nitride Thin Film via Reactive Gas-Timing RF Magnetron Sputtering for Surface Enhanced-Raman Scattering Substrates

“…Recently, transition metal nitride (TMN) has received attention as an alternative plasmonic material with significant potential in the visible to near-infrared ranges of an excitation light [8], comparable to that of traditional noble metals. TMNs (e.g., titanium nitride (TiN), zirconium nitride (ZrN), and hafnium nitride (HfN)) are particularly interesting due to their high melting point, strong mechanical properties, intrinsic chemical stability in harsh environments, and localized plasmon resonances that are extremely comparable to gold [9][10][11][12]. Recent research has demonstrated that HfN exhibits exceptional quality factors for surface plasmon polaritons (SPPs) and LSPR [10,13], which are the real and imaginary components of the dielectric function.…”

“…An extensive study on HfN thin films is aimed at controlling the stoichiometry, which is critical in determining the optical properties [11]. To form the films, physical vapor deposition (PVD) techniques, such as magnetron sputtering or pulsed laser deposition, are generally used.…”