Mg-Doped Nickel Oxide as Efficient Hole-Transport Layer for Perovskite Photodetectors

Abstract

The use of additives in the transport layer can affect film formation, passivate the defects in the bulk or at the surface, and tune the direct bandgap, which promotes the performance of perovskite photodetectors. In this work, the incorporation of Mg into NiO anode interlayers which are used as hole transporting layers (HTLs) in organic−inorganic hybrid perovskite photodetectors is investigated. The device configuration is indium tin oxide (ITO)/NiO or Mg-doped NiO/CH 3 NH 3 PbI 3 /C 60 /bathocuproine (BCP)/Cu. Mg-doped NiO as the HTL for perovskite photodetectors improves the electrical conductivity and the crystallinity of perovskite thin films, which also helps promote energy level matching with the perovskite layer. These can greatly improve hole transport and extraction abilities as well as reduce carrier recombination. The performance of the perovskite photodetector is confirmed by analyzing the current density−voltage characteristics as well as dynamic and transient photocurrent response characteristics. The device with the Mg-doped NiO layer presents a high specific detectivity of 5.3 × 10 13 jones and a large linear dynamic range of 124 dB, which is comparable to that of the commercial Si photodetectors (120 dB). The approach of Mg-doped NiO as HTLs paves a pathway to effectively facilitate the performance of perovskite photodetectors.

Efficient and stable perovskite solar cells using manganese-doped nickel oxide as the hole transport layer

“…Similar phenomenon has been reported by Wang, Sun and their co-workers who utilized Mg-doped NiO x as the HTL for perovskite photodetectors. 26 In this work, the increased Ni 3+ /Ni 2+ ratio means that Mn doping promotes hole transport ability of NiO x . 50 The high-resolution O 1s spectra of the un-doped and Mn-doped NiO x are presented in Fig.…”

“…† The fast decay constant s 1 represents nonradiative capture of free carriers and the slow decay constant s 2 is associated with radiative recombination of carriers from the bulk perovskite. 26,55 The average lifetime (s avg ) was determined with the equation s avg ¼ P (A i s i 2 )/ P (A i s i ), where s i and A i are deduced from the tted curve data. The s avg is calculated to be 91, 52.7, 33.1, 37.7, and 51.3 ns for the perovskite lms on the FTO, un-doped, 0.5, 1, and 2 mol% Mn-doped NiO x , respectively, which is in accordance with the downtrend of PL emission in Fig.…”

“…23,24 In contrast to organic PEDOT:PSS, inorganic p-type nickel oxide (NiO x ) has been extensively employed as the HTL because of its superior hole extraction ability, high transmittance in the visible range, and environmental stability. 25,26 Until now, there have been several methods to prepare NiO x HTL for inverted PSCs, such as sol-gel deposition, atomic layer deposition, spray pyrolysis, and nanoparticle dispersion. [27][28][29][30] The intrinsic hole mobility of solution-processed NiO x is reported to be 10 À5 to 10 À3 cm 2 V À1 s À1 , 31 and therefore doping process is usually adopted to increase holes mobility and hole extraction ability associated with reduced carrier recombination to achieve higher device performance of PSCs.…”

High-Efficiency and Stable Perovskite Photodetectors with an F4-TCNQ-Modified Interface of NiOx and Perovskite Layers

“…where J ph is the photocurrent density measured at the green LED (520 nm), with optical intensities ranging from 10 −7 to 1 mW cm −2 . 35 As described in Figure 10a, the LDR of PD3 is 127.1 dB, significantly higher than that of PD1 (118.7 dB). The high LDR means a stable responsiveness over the low to high light range, which promises to be used in highly sensitive photodetection applications.…”

Inhibited Aggregation of Lithium Salt in Spiro-OMeTAD for Perovskite Solar Cells

“…Organic-inorganic hybrid perovskite has attracted much attention because of its low exciton binding energy, high absorption coefficient, wide spectral range, and long exciton diffusion length. It is a potential candidate material for next-generation photovoltaic devices [1][2][3][4][5][6]. Organic-inorganic hybrid lead halide perovskite solar cells (PSCs) have the characteristics of good solution processability, low cost, and high energy conversion efficiency [7,8] whicd considered to be a new generation of photovoltaic technology [9,10].…”