Scalable Fabrication of Scratch-Proof Transparent Al/F–SnO₂ Hybrid Electrodes with Unusual Thermal and Environmental Stability

Abstract

Fabrication protocols of transparent conducting electrodes (TCEs), including those which produce TCEs of high values of figure of merit, often fail to address issues of scalability, stability, and cost. When it comes to working with high-temperature stable electrodes, one is left with only one and that too, an expensive choice, namely, fluorine-doped SnO2 (FTO). It is rather difficult to replace FTO with a low-cost TCE due to stability issues. In the present work, we have shown that an Al nanomesh fabricated employing the crack template method exhibits extreme thermal stability in air even at 500 °C, compared with that of FTO. In order to fill in the non-conducting island regions present in between the mesh wires, a moderately conducting material SnO2 layer was found adequate. The innovative step employed in the present work relates to the SnO2 deposition without damaging the underneath Al, which is a challenge in itself, as the commonly used precursor, SnCl2 solution, is quite corrosive toward Al. Optimization of spray coating of the precursor while the Al mesh on a glass substrate held at an appropriate temperature was the key to form a stable hybrid electrode. The resulting Al/SnO2 electrode exhibited an excellent transparency of ∼83% at 550 nm and a low sheet resistance of 5.5 Ω/□. SnO2 coating additionally made the TCE scratch-proof and mechanically stable, as the adhesion tape test showed only 8% change in sheet resistance after 1000 cycles. Further, to give FTO-like surface finish, the SnO2 surface was fluorinated by treating with a Selectfluor solution. As a result, the Al/F–SnO2 hybrid film exhibited one order higher surface conductivity with negligible sensitivity toward humidity and volatile organics, while becoming robust toward neutral electrochemical environments. Finally, a custom-designed projection lithography technique was used to pixelate the Al/SnO2 hybrid film for optoelectronic device applications.

Facile and fast preparation of a tung oil-based bendable transparent electrode with mechanical strength and environmental stability via infiltration of silver nanowires into oxygen-inhibited surface layers

“…Therefore, the Δ R / R 0 values after these tests are comparable to other reported BETs and even better than some of them (ESI Table S1†). 2,7,15,20,23,29,36…”

“…Therefore, the DR/R 0 values aer these tests are comparable to other reported BETs and even better than some of them (ESI Table S1 †). 2,7,15,20,23,29,36 A bendable transparent heater (BTH) was constructed to demonstrate a practical application of AgNWs/PAMET1.25 since the AgNWs have a high thermal conductivity value of 430 W m À1 K À1 , as schematically illustrated in Fig. 5a.…”

“…20,21 Great efforts have been made to enhance the interaction between the AgNW layer and the substrate. Functional protection layers such as nanometal oxides, 22,23 small organic molecules 1,24 or polymers, 25,26 have been proposed. As reported, nanometal oxides reduced the mechanical exibility of the conductive layer, while small organic molecules easily got lost and resulted in equipment corrosion.…”

Fabrication of dual-functional electrochromic smart window based on low-cost hybrid transparent electrode coated with a solution-processable polymer

“…51,52 Recently, self-formed crackle template-based metal mesh TCEs have emerged as a potential replacement for their counterparts due to their affordability, scalability, high stability and excellent optoelectronic properties. [51][52][53] The crackle template method has the unique advantage of achieving a very low sheet resistance (<1 ohm per square) of TCEs without compromising their transparency. However, the bare metal mesh TCE consists of non-conducting regions that restrict its smart window applications where a uniform out-of-plane electric eld is required for switching.…”

Advances in SnO2-based perovskite solar cells: from preparation to photovoltaic applications

“…[204][205][206] and F À[207][208][209][210][211] ), metal ions (Li + , 212-215 Mg 2+ , 196,216 Al 3+ , 217,218 Zn 2+ , 143,219 Sb 3+ , 215,220,221 Mo 2+ , 222 Ru 2+ , 209,223 Ga 3+ , 224,225 Zr 2+ , 226,227 Nb 5+ 228-230 and Ta 5+ 231 ) and rare earth ions (Y 3+ , 192,232 La 3+ 233 ) and Nd 3+ 165 (Table…”