02123nas a2200265   4500008004100000022001400041245007200055210006900127260000800196490000700204520129400211653002501505653001801530653001801548653001701566653001601583653002401599100002101623700002301644700002001667700001901687700002901706700001901735856010301754       2023                        eng d  a2194-428800aMulti-bandgap quantum dots ensemble for near-infrared photovoltaics0 aMultibandgap quantum dots ensemble for nearinfrared photovoltaic  cJUN0 v113 a<p>
	Narrow bandgap quantum dots (QDs) are an important class of materials for near-infrared (NIR) optoelectronic devices owing to their size-tunable bandgap and chemical root processing. In photovoltaic applications, NIR QDs could be particularly useful to complement the sub-bandgap transmission loss of NIR solar radiation from perovskite and c-Si solar cells. However, insufficient carrier extraction thickness associated with the narrow NIR excitonic bandwidth of QDs limits the conversion efficacy of the broad NIR solar spectrum. Here, we utilize a multi-bandgap QD ensemble which widens the NIR absorption bandwidth to mimic the broad solar spectrum. A solution-phase ligand passivation strategy is used to control doping properties and energy level alignment of multi-bandgap QDs. We successfully developed bulk-heterojunction solar cells using the multi-bandgap QD ensemble, which yields higher carrier extraction thickness and broader NIR absorption. The gain from NIR absorption and carrier transport resulted in higher short-circuit current generation and power conversion efficiency (PCE) in solar cell devices. The champion device shows 8.73% PCE under 1.5 AM solar illumination and 7.44% and 5.05% PCE for the NIR photons transmitted from perovskite and c-Si layers.</p>
10abulk-heterojunctions10amulti-bandgap10anear-infrared10aquantum dots10asolar cells10asurface passivation1 aMahajan, Chandan1 aDambhare, Neha, V.1 aBiswas, Arindam1 aSharma, Anjali1 aShinde, Dipak, Dattatray1 aRath, Arup, K.  uhttps://library.ncl.res.in/content/multi-bandgap-quantum-dots-ensemble-near-infrared-photovoltaics