Surface Functionalization of Indium Tin Oxide Electrodes by Self-assembled Monolayers for Direct Assembly of Pre-synthesized SnO2 Nanocrystals as Electron Transport Layers

Selective Spin Dewetting for Perovskite Solar Modules Fabricated on Engineered Au/ITO Substrates

“…APTES creates a reactive amine-functionalized surface on ITO due to the silane group’s reaction with the hydroxyl groups on the ITO surface, forming a stable, covalently bonded siloxane layer. This functionalization facilitates the subsequent attachment of SnO 2 NCs [ 38 ].…”

“…In the previous paper, we discussed the self-assembly of the APTES monolayer on ITO and its influence on subsequent SnO 2 NCs ETL and perovskite active layer deposition. This monolayer on ITO covalently bonds with SnO 2 NCs during spin-coating, leading to a uniform, pinhole-free SnO 2 NC layer and promoting the consistent growth of the perovskite film [ 38 ].…”

“…Subsequently, the SnO 2 NCs ETL and perovskite layers, dewetted from the hydrophobic connection electrodes, were selectively and sequentially spin-coated on a previously prepared ITO, followed by the non-selective deposition of a spiro-OMeTAD HTL on the substrate ( Figure 1 e). The conditions of the ETL and perovskite layer deposition were described in the previous work [ 38 ]. Finally, the top Au electrode (100 nm thick) was deposited using thermal evaporation under a high vacuum (1 × 10 −6 torr) through a shadow mask to electrically connect the isolated cells, thus creating perovskite-based mini-modules ( Figure 1 f).…”

“…On the other hand, the spiro-OMeTAD precursor had a notably low contact angle of 10 • , indicating its wetting nature on the HDT surface. Finally, water's contact angle on APTES-assembled ITO was 52 • , signaling a hydrophilic character promoting the deposition of a uniform SnO 2 layer through covalent bonding [38].…”

“…These groups determine the surface energy and functionality of the SAMs, making them either hydrophobic or hydrophilic [ 33 , 34 , 35 , 36 , 37 ]. This feature can be exploited for selective solvent wetting or dewetting and can also affect the interaction of the solute with the surface [ 38 ]. By leveraging these traits, the selective deposition of specific materials on predefined areas can be achieved, enabling precise solar module patterning.…”