4-PhCz

Self-Assembled Monolayer (SAM) Molecule for High Efficiency Perovskite Solar Cells Hole transport layer for p-i-n perovskite solar cells, hole selection layer (HSL), 4-PhCz, (4-(11H-Benzo[a]carbazol-11-yl)butyl) phosphonic acid Overview | Product Information | MSDS | Literature | Related Products | Technical Support 4-PhCz is a self-assembled monolayer material designed for high-efficiency perovskite solar cells and perovskite-silicon tandem solar cells. 4-PhCz features an aromatic asymmetric 11H-benzo[a]carbazole terminal group, a butyl linker and a phosphonic acid anchoring group. 4-PhCz severs as hole selection layer between the substrate and the perovskite active layer. The asymmetric, extended π-conjugated structure of the benzo[a]carbazole terminal not only minimizes aggregation to ensure uniform surface coverage on the substrate but also strengthens the interactions between the self-assembled monolayer and perovskites, a bifacial reinforcement. The larger dipole moment of 2.04 D presented by the terminal group facilitates efficient hole extraction while the smaller contact angle of 11.06° with perovskite precursors enhances film crystallinity. This results a great VOC of 1.273 V with a low voltage loss of 0.397 V relative to the wide bandgap (1.67 eV) of the perovskite solar cell. Monolithic perovskite/silicon tandem based on 4-PhCz as the self-assembled hole transport layer demonstrates a certified efficiency of 31.26% with an impressive VOC of 1.957 V. Moreover, 92% of its initial efficiency after 1000 h of maximum power point tracking (MPPT) is achieved under 1-sun illumination in a nitrogen atmosphere at 25 °C, owing to the suppressed light-induced halide segregation presented by the self-assembled monolayer material 4-PhCz. Serving as hole selective contact for organic solar cells and perovskite solar cells, 4-PhCz is an alternative to PEDOT:PSS with superior performance and the convenience of solution deposition at low concentration, i.e. 1 mM. General Information CAS Number n.a. Chemical Formula C20H20NO3P Molecular Weight 353.35 g/mol Absorption* λmax = 365 nm (in Film) Fluorescence λem (n.a.) HOMO/LUMO HOMO = -5.78 eV, LUMO = -2.52 eV [1] Synonyms (4-(11H-Benzo[a]carbazol-11-yl)butyl) phosphonic acid Classification or Family Benzo[a]carbazole derivatives, Self-assembly monolayers, Hole transport layer, Hole selection layer, p-i-n Perovskite solar cells, Tandem solar cells Product Details Purity ≥98% (HPLC) Melting Point n.a. Appearance Off-white powder/crystals Solution Processing Procedure Typical processing solvents: Methanol, ethanol. IPA, DMF Typical suggested concentration: 1.0 mg/ml or 1.0 mM Typical processing procedure: 4-PhCz is dissolved in ethanol at a concentration of 0.5 mg/ml. The solution is then spin-coated onto a clean and ultraviolet-treated ITO or FTO substrate surface for 30 seconds at 3,000 rpm, followed by annealing for 10 min at 100 ℃. (from device fabrication, DOI: 10.1002/adma.202504520). Chemical Structure 4-PhCz, (4-(11H-Benzo[a]carbazol-11-yl)butyl) phosphonic acid chemical structure MSDS Documentation 4-PhCz MSDS Sheet Literature and Reviews C. Guo et al. (2025), Bifacially Reinforced Self-Assembled Monolayer Interfaces for Minimized Recombination Loss and Enhanced Stability in Perovskite/Silicon Tandem Solar Cells, Adv. Mater., 37 (29), 2504520; DOI: 10.1002/adma.202504520. J. Wang et al. (2026), Asymmetric Self-Assembled Molecule with High Dipole Moment for Efficient Wide-Bandgap Perovskite Solar Cells and Tandems, Adv. Mater., 38 (13), e23338; DOI: 10.1002/adma.202523338. Related Products [[collection handle="self-assembled-monolayers" limit="5"]] Self-Assembled Monolayers Perovskite Materials Semiconducting Molecules