Improving All‐Inorganic Perovskite Photodetectors by Preferred Orientation and Plasmonic Effect

Abstract

All-inorganic perovskites have high carrier mobility, long carrier diffusion length, excellent visible light absorption, and well overlapping with localized surface plasmon resonance (LSPR) of noble metal nanocrystals (NCs). The high-performance photodetectors can be constructed by means of the intrinsic outstanding photoelectric properties, especially plasma coupling. Here, for the first time, inorganic perovskite photodetectors are demonstrated with synergetic effect of preferred-orientation film and plasmonic with both high performance and solution process virtues, evidenced by 238% plasmonic enhancement factor and 10 on/off ratio. The CsPbBr and Au NC inks are assembled into high-quality films by centrifugal-casting and spin-coating, respectively, which lead to the low cost and solution-processed photodetectors. The remarkable near-field enhancement effect induced by the coupling between Au LSPR and CsPbBr photogenerated carriers is revealed by finite-difference time-domain simulations. The photodetector exhibits a light on/off ratio of more than 10 under 532 nm laser illumination of 4.65 mW cm . The photocurrent increases from 0.67 to 2.77 μA with centrifugal-casting. Moreover, the photocurrent rises from 245.6 to 831.1 μA with Au NCs plasma enhancement, leading to an enhancement factor of 238%, which is the most optimal report among the LSPR-enhanced photodetectors, to the best of our knowledge. The results of this study suggest that all-inorganic perovskites are promising semiconductors for high-performance solution-processed photodetectors, which can be further enhanced by Au plasmonic effect, and hence have huge potentials in optical communication, safety monitoring, and biological sensing.

Giant Photo‐Induced Current Enhancement in a Core–Shell‐Type Quantum‐Dot Thin Film

“…The ratio of I Light to I Dark reached extremely large values by the V G scan optimization, which is larger than 10 5 . To the best of our knowledge, I Light / I Dark obtained here is larger than the values reported in previous studies with FET‐photodetectors 33,34,39. In photo‐FETs, I Light / I Dark generally shows a maximum at a certain V G because I Dark begins to increase at V G larger than a threshold voltage 8.…”

Recent advances on organic‐inorganic hybrid perovskite photodetectors with fast response

“…Compared with the photovoltaic photodetectors, the photoconductive photodetectors breaks through the EQE limit of 100% due to the different working principle, so that higher responsivity can be obtained. Therefore, the sensitivity of photoconductive photodetectors can be further improved in combination with the suppressing noise . However, the intrinsic contradictions between the responsivity and response time always exist.…”

An Innovative Postdeposition Annealing Approach Producing Centimeter‐Scale In2O3/In2(TeO3)3 Bulk Heterojunction Thin Film for Room‐Temperature Persistent Photoconductivity

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extensive applications such as optoelectronic memory, [1,2] light-enhanced gas sensing, [3][4][5] imaging, [6] photocatalysis, [7,8] photovoltaics, [9,10] and radiation detection. [11] However, thus far, the majority of researchers focus on the conventional rapid photoswitching, [12][13][14][15][16] while PPC phenomena have attracted much less attention. Traditionally, PPC phenomena were commonly found in nanomaterial-based devices with large surface to volume ratio, [2,[17][18][19][20][21] in which the spontaneous surface potential spatially separated the photogenerated electron-hole pairs.

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