Oxidative Spin-Spray-Assembled Coordinative Multilayers as Platforms for Capacitive Films.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Layer-by-layer (LbL) assembly is a common technique for fabricating multilayer films.
• Conventional dip LbL methods are time-consuming for growing thick films.
• Oxidative multilayers serve as platforms for generating conducting polymer and melanin-type films.

Purpose of the Study:

• To develop a rapid method for preparing coordinative oxidative multilayers using spin-spray LbL assembly.
• To investigate the potential of these multilayers as capacitive layers for supercapacitors in biodegradable electronics.
• To evaluate the performance of films before and after electrochemical reduction of graphene oxide (GO).

Main Methods:

• Spin-spray-assisted layer-by-layer (LbL) assembly using Ce(IV), inorganic polyphosphate (PP), and graphene oxide (GO).
• Fabrication of (PP/Ce/GO/Ce) tetralayers.
• Deposition of poly(3,4-ethylenedioxothiophene) (PEDOT) and 5,6-dihydroxyindole for melanin-type films.
• Electrochemical reduction of GO to reduced graphene oxide (rGO).

Main Results:

• Spin-spray LbL significantly reduces fabrication time for thick multilayers, yielding linear film growth.
• PEDOT and melanin-type films deposited on the multilayers exhibit excellent capacitive properties.
• Areal capacitance reached ~1.6 mF cm⁻² with 20 tetralayers, and specific capacitances were ~130 F cm⁻³ (volumetric) and ~65 F g⁻¹ (mass).
• Performance was enhanced after electrochemical reduction of GO to rGO.

Conclusions:

• Spin-spray LbL is an efficient method for producing stratified oxidative multilayers.
• These multilayers are promising platforms for creating high-performance capacitive layers for biodegradable supercapacitors.
• The charge transfer kinetics are favorable, especially with rGO, indicating suitability for energy storage applications.