Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• ]. In 1997, Era et al. first presented a chromophore-containing organic–inorganic perovskite [21]. They observed an enhanced phosphorescence of the included naphthalene [22], which was explained by an efficient energy transfer from Wannier excitons from the semiconducting perovskite layer to the triplet

• states of naphthalene [23]. Regarding the electronic alignment of molecular orbitals, valence and conduction bands, the chromophore may serve as a quantum well [24]. The energy transfer between the semiconducting perovskite layer and the chromophore can easily be influenced by the chemical structure and

• 2D systems, i.e., molecules incorporated into the layers and species bound to the exterior surface of the particles. Energy-level diagram of 2D-AzoC2, 2D-AzoOC4 and 2D-AzoOC12 as function of the distance between the perovskite layer and the azobenzene moiety. UV–vis and PESA measurements can be found

Recent progress in perovskite solar cells: the perovskite layer

• Xianfeng Dai,
• Ke Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2020, 11, 51–60, doi:10.3762/bjnano.11.5

• , paving the way for their commercialization. In the closing section of this review, some future critical challenges are outlined, and the prospect of commercialization of PSCs is presented. Keywords: coating techniques; perovskite layer; perovskite solar cells (PSCs); perovskite structure; photovoltaic

• commercialization. A few unprecedented achievements have been made that are highly beneficial for the large-scale commercial application of PSCs in the future [8][9][10][11]. For PSCs, the perovskite layer, which is sandwiched between an electron extraction layer and a hole extraction layer, is fundamental. It is

• the core of PSCs, which is closely related to the performance of the overall device. For example, it has been widely recognized that the PCE of the PSCs depends largely on the morphology and the crystalline quality of the perovskite layer [12]. Therefore, recent major challenges are to simultaneously

Polyvinylpyrrolidone as additive for perovskite solar cells with water and isopropanol as solvents

• Chen Du,
• Shuo Wang,
• Xu Miao,
• Wenhai Sun,
• Yu Zhu,
• Chengyan Wang and
• Ruixin Ma

Beilstein J. Nanotechnol. 2019, 10, 2374–2382, doi:10.3762/bjnano.10.228

• cm2. All samples were measured in air (25 °C). Results and Discussion Figure 1 illustrates how the PSCs were prepared. The PSCs of this study comprises a SnO2 electron transfer layer (ETL), a MAPbI3 coating, a Spiro-OMeTAD HTL as well as a gold electrode. In a first step, the perovskite layer was

• irradiated by UV/ozone. The following most critical point in the production of the perovskite layer was to spin the lead nitrate onto the SnO2 ETL. Then, the layer was introduced into a bath of MAX solution for 500 s, and finally dried by spinning and annealing at 120 °C for a period of 10 min. The SEM

• attributed to the appearance of voids on the surface of the perovskite layer, which results in a higher recombination rate of the carriers [34]. Figure 5 shows electrical impedance spectroscopy (EIS) measurements at a voltage bias of 0 V under one-sun light intensity with the test frequency ranging from 0.1

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• perovskite layer under a reductive atmosphere, for example, in the presence of hydrazine vapors [119]. The conversion of Sn4+ into Sn2+, which can be described as 2SnI62– + N2H4 = 2SnI42– + N2 + 2HI, results in a reduction of the density of Sn2+ vacancies (Figure 5a) suppressing the undesirable p-type

Know your full potential: Quantitative Kelvin probe force microscopy on nanoscale electrical devices

• Amelie Axt,
• Ilka M. Hermes,
• Victor W. Bergmann,
• Niklas Tausendpfund and
• Stefan A. L. Weber

Beilstein J. Nanotechnol. 2018, 9, 1809–1819, doi:10.3762/bjnano.9.172

• distribution, which we assigned to unbalanced charge extraction from the perovskite layer. The absence of local features in the potential distribution imaged with AM lift mode KPFM, the potential offset of +1 V, as well as the reduced potential increase upon illumination suggested that the spatial and