Room-temperature direct synthesis of semi-conductive PbS nanocrystal inks for optoelectronic applications

Abstract

Lead sulphide (PbS) nanocrystals (NCs) are promising materials for low-cost, high-performance optoelectronic devices. So far, PbS NCs have to be first synthesized with long-alkyl chain organic surface ligands and then be ligand-exchanged with shorter ligands (two-steps) to enable charge transport. However, the initial synthesis of insulated PbS NCs show no necessity and the ligand-exchange process is tedious and extravagant. Herein, we have developed a direct one-step, scalable synthetic method for iodide capped PbS (PbS-I) NC inks. The estimated cost for PbS-I NC inks is decreased to less than 6 $·g−1, compared with 16 $·g−1 for conventional methods. Furthermore, based on these PbS-I NCs, photodetector devices show a high detectivity of 1.4 × 1011 Jones and solar cells show an air-stable power conversion efficiency (PCE) up to 10%. This scalable and low-cost direct preparation of high-quality PbS-I NC inks may pave a path for the future commercialization of NC based optoelectronics.

Facet Control for Trap‐State Suppression in Colloidal Quantum Dot Solids

“…Therefore, a higher carrier collection efficiency is expected, accounting for the higher J SC of the o ‐QD solar cells. Finally, space‐charge‐limited current (SCLC) measurements [ 49 ] confirm that the o ‐QD solids have larger mobility and a lower trap density than the to ‐QD solids, as shown in Figure 7f. As the lead halide treated PbS QD solids exhibit as n‐type semiconductors, [ 12,19 ] the SCLC measurement adopts an electron‐only device structure composed of indium‐doped tin oxide (ITO)/QD film/Ag.…”

Room-temperature formation of CdS magic-size clusters in aqueous solutions assisted by primary amines

“…It is noteworthy that BTA has been claimed to assist the decomposition of a TU derivative in N,N-dimethylformamide (DMF) during the nucleation and growth of PbS nanocrystals 43 . In the absence of CdCl 2 , Supplementary Fig.…”

PbS Colloidal Quantum Dot Inks for Infrared Solar Cells

“…Direct synthesis of CQD inks was reported recently, which could simplify the preparation of CQD inks. Wang et al. (2019) used PbI 2 and diphenylthiourea (DPhTA) as the lead source and sulfur source, respectively, accompanied by the injection of BTA into the reaction system.…”