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We report on the successful creation of nonthermal plasma-synthesized phorphorus and boron co-doped Si nanocrystals (PB:Si NCs) with diameters (DNC) ranging from 2.9 to 7.3 nm. Peak photoluminescence (PL) emission energies for all PB:Si NC diameters are ca. 400–500 meV lower than the excitonic emission values in intrinsic Si NCs, which can be attributed to prevalent donor–acceptor (D–A) transitions within the co-doped system. This D–A transition model is further evidenced by PL lifetimes within the range of 40–80 μs, faster than what is observed for intrinsic Si NCs. By reducing the level of confinement within PB:Si NCs (i.e., DNC > 4 nm), we are able to red-shift the near-infrared (NIR)-emitting D–A transitions to below the band gap of bulk Si (1.12 eV). We quantify the PL quantum yield (PLQY) for a range of DNC and show that the plasma method can achieve reasonably high PLQY values (12% for DNC = 2.9 nm), even without any optimization of the synthesis or surface chemistry. We posit that perfect charge c...

Colloidally synthesized quantum-confined semiconducting spherical nanocrystals, often referred to as quantum dots (QDs), offer a high degree of chemical, optical, and electronic tunability. As a result, there is an increasing interest in employing colloidal QDs for electronic and optical applications that is reflected in a growing number of publications. In this protocol we provide detailed procedures for the fabrication of QD solar cells specifically employing PbSe and PbS QDs. We include details that are learned through experience, beyond those in typical methodology sections, and include example pictures and videos to aid in fabricating QD solar cells. Although successful solar cell fabrication is ultimately learned through experience, this protocol is intended to accelerate that process. The protocol developed here is intended to be a general starting point for developing PbS and PbSe QD test bed solar cells. We include steps for forming conductive QD films via dip coating as well as spin coating. Fin...