Phosphorylcholine chloride

Small Self-Assembled Monolayer Molecule for High Efficiency Solar Cells

Phosphorylcholine chloride, multifunctional electron and hole interface material for perovskite solar cells

Phosphocholine chloride (N,N,N-Trimethyl-2-(phosphonooxy)ethanaminium chloride, CAS No. 107-73-3) is also known as phosphocholine chloride or choline phosphates. It is an organic ammonium salt with an ethyl linker between the ammonium cation and a phosphonic acid function group. The phosphonic acid function group serves as an anchor to the surface of metal oxides.

Multifunctional phosphocholine chloride has been engaged to modify the interface between tin dioxide (SnO₂) electron transport layer and the perovskite active layer by the doping of the SnO₂. Not only phosphocholine chloride reduces oxygen vacancy defects in the SnO₂ but also it passivates defects in the perovskite layer. As a result, higher quality of perovskite film and improved conductivity and electron mobility of SnO₂ are achieved. A power conversion efficiency (PCE) of 24.34% with a retention of 91.44% of its initial efficiency is gained even after 1200 h of ambient exposure at 25 °C and 25% relative humidity without encapsulation.

Phosphocholine chloride has also been employed as a self-assembled monolayer (SAM) material, to form a Co-SAM with Me-4PACz to improve the monolayer coverage and reduce leakage current. Phosphocholine chloride has multiple functions serving as a co-doped SAM to the metal oxide surface. The phosphate group and chloride ions (Cl⁻) in PC can inhibit nickel oxide (NiO_x) surface defects, and the quaternary ammonium ions and Cl⁻ can fill organic cations and halogen vacancies in the perovskite film to enable defects passivation. The Co-SAM strategy can also promote the growth of perovskite crystals, collaboratively solve the problem of buried defects, suppress nonradiative recombination, accelerate carrier transmission, and relieve the residual stress of the perovskite film.

As an antigenic cell-surface component, phosphocholine chloride is also found on many commensal and pathogenic bacteria that reside in the upper airway.

Solution Processing Procedure

Typical processing solvents: H₂O, ethanol
Typical concentration: 0.5, 1.0, or 2.0 mg/ml

Typical processing procedure: Phosphorylcholine chloride is dissolved in deionized water at the concentration of 1.0 mg/mL and stirred for 3 h. Phosphorylcholine chloride solution is then spin-coated on the SnO₂ film at 5000 rpm and annealed at 100 °C for 10 min (DOI: 10.1002/adfm.202405556).

Me-4PACz (0.5 mg/mL) and phosphorylcholine chloride (0.2 mg/mL) in ethanol Co-SAM solution is spin-coated on NiO_x substrates for 30 s at 4000 rpm, then annealed for 10 min at 100 ℃. Subsequently, the substrate is washed with pure ethanol through spin-coating for 30 s at 4000 rpm, then annealed for 5 min at 100 °C (DOI: 10.1002/adma.202311970).

General Information

Product Details

Chemical Structure

MSDS Documentation

Phosphorylcholine chloride MSDS Sheet

References

• Y. Yuan et al. (2024); High-Efficiency and Stable Perovskite Solar Cells via Buried Interface Modification with Multi-Functional Phosphorylcholine Chloride, Adv. Funct. Mater., 2405556; DOI: 10.1002/adfm.202405556.
  
• X. Meng et al. (2023); Choline Derivative as a Multifunctional Interfacial Bridge through Synergistic Effects for Improving the Efficiency and Stability of Perovskite Solar Cells, Small, 20 (25), 2310275; DOI: 10.1002/smll.202310275.
  
• Q. Cao et al. (2024); Co-Self-Assembled Monolayers Modified NiOx for Stable Inverted Perovskite Solar Cells, Adv. Mater., 36 (16), 2311970; DOI: 10.1002/adma.202311970