02244nas a2200229   4500008004100000022001400041245008800055210006900143260000800212300001400220490000600234520150700240653001901747653001601766653001601782653002401798653001601822100001901838700002101857700001901878856011701897       2020                        eng d  a2574-096200aReduction of trap and polydispersity in mutually passivated quantum dot solar cells0 aReduction of trap and polydispersity in mutually passivated quan  cSEP  a8903-89110 v33 a<p>Control over surface passivation is a key to manage the optoelectronic properties in low-dimensional nanomaterials because of their high surface-to-volume ratios. Tunable band gap quantum dots (QDs) are a potential building block for the development of optoelectronic devices like solar cells, photodetectors, and light-emitting diodes. Long and insulating surface ligands of colloidally synthesized QDs are exchanged by short ligands to attain compact arrangement in thin films to facilitate the charge transport process. However, the ligand exchange process often resulted in reduced surface passivation, inhomogeneous QD fusion, and deterioration of energy band gap, which adversely impact their performance in solar cells. Here, we introduce a surface passivation strategy where the QDs are mutually passivated by the organic ligand 3-methyl mercapto propionate and inorganic halometallate ligands to develop a conducting QD ink. The mutually passivated QDs (MPQDs) show significant improvement in optoelectronic properties in maintaining the trap-free energy band gap and size monodispersity. The photovoltaic performance of MPQDs shows a 33% average increase in power conversion efficiency (PCE) over the conventional halometallate passivation to attain 9.6% PCE in MPQD solar cells. The improvements in photovoltaic parameters are corroborated by the reduction in density of the intermediate trap states and an increase in depletion width and diffusion length in MPQD-based solar cells.</p>
10apolydispersity10aquantum dot10asolar cells10asurface passivation10atrap states1 aSharma, Ashish1 aMahajan, Chandan1 aRath, Arup, K.  uhttps://library.ncl.res.in/content/reduction-trap-and-polydispersity-mutually-passivated-quantum-dot-solar-cells