Synergistic Additive‐Assisted Growth of 2D Ternary In 2 SnS 4 with Giant Gate‐Tunable Polarization‐Sensitive Photoresponse

2D ternary materials exhibit great promise in the field of polarization-sensitive photodetectors due to the low-symmetry crystal structure. However, the realization of ternary material growth is still a huge challenge because of the complex reaction process. Here, for the first time, 2D ternary In2 SnS4 flakes are obtained via synergistic additive of salt and molecular sieve-assisted chemical vapor deposition. Raman vibration mode of In2 SnS4 flakes exhibits polarization-dependent properties. The polarization-resolved absorption spectroscopy and azimuth-dependent reflectance difference microscopy further confirm its anisotropy of in-plane optical absorption and reflection. Besides, the In2 SnS4 flake based device on mica shows ultrafast rising and decay rates of ≈20 and 20 µs. Impressively, In2 SnS4 flake based phototransistor demonstrates giant gate-tunable polarization-sensitive photoresponse: the dichroic ratio can be adjusted in the range of 1.13-1.70 with gate voltage varying from -35-35 V. This work provides an effective means for modulating the polarization-sensitive photoresponse, which may significantly promote the research progress of polarization-sensitive photodetectors.