02150nas a2200229   4500008004100000022001400041245009400055210006900149260000800218300001600226490000700242520140100249653001101650653001301661653001601674653001501690653002401705100002201729700002701751700001901778856012301797       2019                        eng d  a1944-824400aThiol and halometallate, mutually passivated quantum dot ink for photovoltaic application0 aThiol and halometallate mutually passivated quantum dot ink for   cJUL  a26100-261080 v113 a<p>Tunable-band-gap colloidal QDs are a potential building block to harvest the wide-energy solar spectrum. The solution-phase surface passivation with lead halide-based halometallate ligands has remarkably simplified the processing of quantum dots (QDs) and enabled the proficient use of materials for the development of solar cells. It is, however, shown that the hallometalate ligand passivated QD ink allows the formation of thick crystalline shell layer, which limits the carrier transport of the QD solids. Organic thiols have long been used to develop QD solar cells using the solid-state ligand exchange approach. However, their use is limited in solution-phase passivation due to poor dispersity of thiol-treated QDs in common solvents. In this report, a joint passivation strategy using thiol and halometallate ligand is developed to prepare the QD ink. The mutually passivated QDs show a 50% reduction in shell thickness, reduced trap density, and improved monodispersity in their solid films. These improvements lead to a 4 times increase in carrier mobility and doubling of the diffusion length, which enable the carrier extraction from a much thicker absorbing layer. The photovoltaic devices show a high efficiency of 10.3% and reduced hysteresis effect. The improvement in surface passivation leads to reduced oxygen doping and improved ambient stability of the solar cells.</p>
10aligand10amobility10aquantum dot10asolar cell10asurface passivation1 aMandal, Debranjan1 aGoswami, Prasenjit, N.1 aRath, Arup, K.  uhttp://library.ncl.res.in/content/thiol-and-halometallate-mutually-passivated-quantum-dot-ink-photovoltaic-application01763nas a2200229   4500008004100000022001400041245010300055210006900158260000900227300001600236490000700252520100500259653001101264653001301275653001601288653001501304653002401319100002201343700001901365700001901384856013001403       2021                        eng d  a1944-824400aReduction of hydroxyl traps and improved coupling for efficient and stable quantum dot solar cells0 aReduction of hydroxyl traps and improved coupling for efficient   cOCT   a46549-465570 v133 aProgress in quantum dot (QD)-based solar cells has been underpinned by the improvements in surface passivation and advancements in device engineering. Acute control over the surface properties is crucial to restrict the formation of in-gap trap states and improve the QD coupling in achieving conducting QD films. In this report, we demonstrate a solution-phase hybrid passivation strategy, which is beneficial in removing detrimental hydroxyl traps and improving the coupling between QDs by reducing the interdot distance. Advancement in surface passivation is translated to the long carrier lifetime, higher carrier mobility, and superior protection toward degradations in QD solids. The performance of solar cell devices is increased by 26% to reach an efficiency of 10.6%, compared to the state-of-the-art lead halide passivated solar cells. The improvement in solar cell performance is supported by the reduction of trap states and an 80 nm increase in thickness of the light-absorbing QD layer.10aligand10amobility10aquantum dot10asolar cell10asurface passivation1 aMandal, Debranjan1 aDambhare, Neha1 aRath, Arup, K.  uhttp://library.ncl.res.in/content/reduction-hydroxyl-traps-and-improved-coupling-efficient-and-stable-quantum-dot-solar-cells02378nas a2200277   4500008004100000022001400041245014500055210006900200260000900269300001600278490000700294520143500301653002101736653001701757653002301774653001701797653001501814100002901829700001901858700002301877700002101900700002001921700001801941700001901959856012201978       2024                        eng d  a1944-824400aSynthesis and processing strategy for high-bandgap PbS quantum dots: a promising candidate for harvesting high-energy photons in solar cells0 aSynthesis and processing strategy for highbandgap PbS quantum do  cAUG   a42522-425330 v163 a<p>
	The wide tunability of the energy bandgap of colloidal lead sulfide (PbS) quantum dots (QDs) has uniquely positioned them for the development of single junction and tandem solar cells. While there have been substantial advancements in moderate and narrow bandgap PbS QDs-ideal for single junction solar cells and the bottom cell in tandem solar cells, respectively; progress has been limited in high-bandgap PbS QDs that are ideally suited for the formation of the top cell in tandem solar cells. The development of appropriate high bandgap PbS QDs would be a major advancement toward realizing efficient all-QD tandem solar cells utilizing different sizes of PbS QDs. Here, we report a comprehensive approach encompassing synthetic strategy, ligand engineering, and hole transport layer (HTL) modification to implement high-bandgap PbS QDs into solar cell devices. We achieved a greater degree of size homogeneity in high-bandgap PbS QDs through the use of a growth retarding agent and a partial passivation strategy. By adjusting the ligand polarity, we successfully grow HTL over the QD film to fabricate solar cells. With the aid of an interface modifying layer, we incorporated an organic HTL for the realization of high-performance solar cells. These solar cells exhibited an impressive open-circuit voltage of 0.824 V and a power conversion efficiency of 10.7%, marking a 360% improvement over previous results.</p>
10acharge transport10alead sulfide10aligand passivation10aquantum dots10asolar cell1 aShinde, Dipak, Dattatray1 aSharma, Anjali1 aDambhare, Neha, V.1 aMahajan, Chandan1 aBiswas, Arindam1 aMitra, Anurag1 aRath, Arup, K.  uhttp://library.ncl.res.in/content/synthesis-and-processing-strategy-high-bandgap-pbs-quantum-dots-promising-candidate