Growth, Raman Scattering Investigation and Photodetector Properties of 2D SnP

Abstract

As an important metal phosphides material, 2D tin phosphides (SnPx 0 < x ≤ 3) have been theoretically predicted to have intriguing physicochemical properties and potential applications in electronics, optoelectronics, and energy fields. However, the synthesis of high‐quality 2D SnP single crystal has not been reported due to the lack of efficiency and reliable growth method. Here, a facile atmospheric pressure chemical vapor deposition (APCVD) method is developed to realize the growth of high‐quality 2D SnP nanosheets, by employing tin (Sn) foil as both liquid metal substrates and reaction precursor. Temperature‐dependent and angle‐resolved polarization Raman spectra observed Raman peaks located at 142.6, 303.3, and 444.2 cm‐1 are concluded to belong to A1g mode, which are consistent with the theoretical calculation results. Moreover, the field‐effect transistor (FET) devices based on SnP nanosheets show a typical n‐type characteristic with an on/off ratio of 103 at 200 K. SnP nanosheets also demonstrate excellent photoresponse performance under the illumination of 473, 532, and 639 nm lasers, which can be tuned by Vgs, Vds, and light power density. It is believed that these findings can provide the first‐hand experimental information for the future study of 2D SnP nanosheets.

Raman Spectroscopy of the Trapezoidal Bi2O2Se

“…This phenomenon can be explained by the inharmonicity of the lattice vibrations, which is related to the temperature-dependent volume expansion and the inharmonic phonon-phonon coupling in the crystal. [22] The linear dependence of the Raman shifts on temperature is shown in Figure 5ce, which can be expressed by the formula [23] 𝜔 (T) = 𝜔 0 + 𝜒T (5)…”

“…This phenomenon can be explained by the inharmonicity of the lattice vibrations, which is related to the temperature‐dependent volume expansion and the inharmonic phonon–phonon coupling in the crystal. [ 22 ] The linear dependence of the Raman shifts on temperature is shown in Figure 5c–e, which can be expressed by the formula [ 23 ] $$$$\begin{eqnarray}\omega \left( T \right) = {\omega }_0 + \chi T\end{eqnarray}$$$$where ω 0 and ω ( T ) are, respectively, the frequency of vibration mode at absolute zero and the measured temperature, χ is the first‐order temperature coefficient of the corresponding vibration mode. On the (001) top plane, a value of χ = −0.025 ± 0.001 cm −1 K −1 is obtained for A 1g mode in Figure 5c, while the χ for A 1g mode is −0.018 ± 0.001 cm −1 K −1 on the slope of trapezoidal Bi 2 O 2 Se (Figure 5d), lower than that on top plane.…”

First-principles study of carrier mobility and strain effect in MX (M=Sn, Pb; X=P, As) monolayers

“…SnP-based nanosheets display outstanding properties such as high switching ratios, great responsivity, and superior photoresponsive qualities. SnP synthesis methods typically include hydrothermal synthesis and atmospheric pressure chemical vapor deposition, through which researchers have successfully cultivated high-quality 2D SnP nanosheets on liquid metal substrates [18]. However, neither method allows for control over the crystal structure and morphology of SnP nanomaterials, significantly limiting their application.…”