03163nas a2200301   4500008004100000022001400041245017900055210006900234260000800303300001400311490000700325520211500332653001702447653002302464653001802487653001702505653001502522653002102537100001902558700002902577700002102606700002302627700002002650700001802670700002502688700001902713856012902732       2025                        eng d  a1944-824400aSynergistic improvement of narrow bandgap PbS quantum dot solar cells through surface ligand engineering, near-infrared spectral matching, and enhanced electrode transparency0 aSynergistic improvement of narrow bandgap PbS quantum dot solar   cJAN  a6614-66250 v173 a<p>
	The tunability of the energy bandgap in the near-infrared (NIR) range uniquely positions colloidal lead sulfide (PbS) quantum dots (QDs) as a versatile material to enhance the performance of existing perovskite and silicon solar cells in tandem architectures. The desired narrow bandgap (NBG) PbS QDs exhibit polar (111) and nonpolar (100) terminal facets, making effective surface passivation through ligand engineering highly challenging. Despite recent breakthroughs in surface ligand engineering, NBG PbS QDs suffer from uncontrolled agglomeration in solid films, leading to increased energy disorder and trap formation. The limited NIR transparency of commonly used indium-doped tin oxide (ITO) electrodes and inadequate NIR radiation from commercially available solar simulators further compromise the true performance of NBG PbS QDs in solar cells. Here, we employ a hybrid ligand strategy based on inorganic cadmium halide and organic thiol molecules, leading to the partial substitution of surface Pb atoms with Cd heteroatoms. This hybrid ligand strategy substantially reduces undesired QD fusion in solid films, improving the photophysical and electronic properties. By modulating the thickness of the ITO layer and managing refraction loss through a ZnO layer coating, we improved NIR transparency to above 80%. We combine an NIR light source with a solar simulator to achieve near-ideal spectral matching for a broader range with standard AM1.5G illumination. Enhancements in surface passivation of QDs, improvements in NIR transparency of electrodes, and a spectral matched light source setup help us achieve solar cell power conversion efficiencies of 12.4%, 4.48%, and 1.37% under AM 1.5G, perovskite filter, and silicon filter illuminations, respectively. A record open-circuit voltage (V oc) of 0.54 V and short-circuit current density (J sc) of 38.5 mA/cm2 are achieved under AM 1.5G illumination. We attribute these advancements in photovoltaic parameters to the reduction in Urbach tail states and intermediate trap density originating from superior surface passivation of QDs.</p>
10alead sulfide10aligand passivation10anear-infrared10aquantum dots10asolar cell10atandem solarcell1 aSharma, Anjali1 aShinde, Dipak, Dattatray1 aMahajan, Chandan1 aDambhare, Neha, V.1 aBiswas, Arindam1 aMitra, Anurag1 aGirade, Vrushali, S.1 aRath, Arup, K.  uhttps://library.ncl.res.in/content/synergistic-improvement-narrow-bandgap-pbs-quantum-dot-solar-cells-through-surface-ligand