Additive Engineering of the CuSCN Hole Transport Layer for High-Performance Perovskite Semitransparent Solar Cells

Abstract

CuSCN has been widely considered a promising candidate for low-cost and high-stable hole transport material in perovskite semitransparent solar cells (STSCs). However, the low conductivity of the solution-processed CuSCN hole transport layer (HTL) hinders the hole extraction and transport in devices, which makes it hard to achieve devices with high performance. Herein, we report a facile additive engineering approach to optimize the p conductivity of CuSCN HTLs in perovskite STSCs. The n-butylammonium iodide additive facilitates the formation of Cu2+ and generates more Cu vacancies in the CuSCN HTL. This realizes a significant enhancement of the hole concentration and p conductivity of the film. Moreover, the additive improves the solubility of the CuSCN precursor solution and results in a uniform coverage on the perovskite active layer. Therefore, the perovskite STSC with a high power conversion efficiency (PCE) of 19.24% has been achieved, which is higher than that of the spiro-OMeTAD (18.83%) and CuSCN (17.45%) counterparts. In addition, the unencapsulated CuSCN-based device retains 87.5% of the initial PCE after 20 days in the ambient atmosphere.

All-Inorganic Hydrothermally Processed Semitransparent Sb2S3 Solar Cells with CuSCN as the Hole Transport Layer

“…The PCE of devices based on the CuSCN HTL layer is highly sensitive at lower values of both μ h and N A and saturates beyond certain minimum values (μ h > 10 –4 cm 2 V –1 s –1 and N A > 10 17 cm –3 ). These values are quite achievable in CuSCN thin film without doping as in the current investigation and reported elsewhere. , Furthermore, a comparison table of reported simulations of planar Sb 2 S 3 solar with different device structures is presented in Table S2. The device with a CuSCN HTL in the ideal case (low bulk defect density of 10 12 cm –3 and no interface traps) should theoretically perform as well as other HTLs.…”

“…To further investigate the improvement of device performance (especially the V OC ), surface potentials suggesting a p-type character with high carrier density (>10 17 cm −3 ). 50 Another important attribute of employing CuSCN with a high E F (and E v ) is the elimination of the Fermi-level pinning phenomenon. Savadogo and Mandal 67 reported that the Schottky barrier height was independent of the work function of the top contact and concluded the Fermi level was pinned near the midgap of Sb 2 S 3 (around −4.5 eV).…”

Tris(pentafluorophenyl)borane–water complex doped Spiro-TTB for high-efficiency and stable perovskite solar cells

“…As in previous work, the structure of ST-PSC is composed of ITO/SnO 2 /perovskite/HTL/MoO x /ITO, as shown in Fig. S21 † 34 . This ST-PSC yields a high PCE of 19.35% with a V OC of 1.14 V, a J SC of 21.29 mA cm −2 , and an FF of 79.43% in Fig.…”

DFT Computational Approach to Interfacial Recombination in MXene-Assisted Perovskite Solar Cells with β-CuSCN HTL

“…It has been reported that CuSCN-based devices are more stable in an air atmosphere than their Spiro-OMeTAD counterparts. 44 In 2017, Gratzel's group developed CuSCN HTL-based opaque PSCs that had a PCE of 20% and much better stability than Spiro-OMeTAD-based PSCs. 45 Furthermore, CuSCN doped with p-type elements could result in reduced trap state density and vacancy defects, thereby improving thermal resistance and preventing elemental interdiffusion, which is advantageous to improving the device's thermal stability.…”

“…Owing to its wide bandgap (3.7–3.9 eV), it transmits light throughout the visible and near-infrared spectrum. , Furthermore, β-CuSCN manifests good stability and high mobility of 0.01–0.1 cm 2 V –1 s –1 compared to its counterpart, Spiro-OMeTAD (∼10 –3 cm 2 V –1 s –1 ). It has been reported that CuSCN-based devices are more stable in an air atmosphere than their Spiro-OMeTAD counterparts . In 2017, Gratzel’s group developed CuSCN HTL-based opaque PSCs that had a PCE of 20% and much better stability than Spiro-OMeTAD-based PSCs .…”