Preparation and High Photocurrent Generation Enhancement of Self-Assembled Layered Double Hydroxide-Based Composite Dye Films

Abstract

Understanding photocurrent conversion of layered double hydroxide (LDH) materials will be a key step in the future application of these materials to light-capturing molecular devices. In the present study, ultrathin nickel−iron layered double hydroxide/dye (NF-LDH/dye) Langmuir−Blodgett (LB) semiconductor films were prepared using an LB device and deposited on an indium tin oxide (ITO) substrate as a photoanode. The photoelectric conversion efficiency of the prepared LB semiconductor film materials was tested. A comparative experiment was performed to effectively explore the photoelectric conversion performances of the LB semiconductor film materials. Specifically, the NF-LDH cast film electrode, the dye cast film electrode, and an ultrathin composite LB film electrode were used as typical samples to explore photoelectric conversion performances. The electrochemical workstation was used to study the photocurrent density, linear scanning voltammetry curve, and electrochemical impedance spectroscopy of LB film electrodes with different layers. The results show that the film electrode cast by LDH alone or dye alone produces weak photocurrent. The photoelectric conversion efficiency of the LB film electrode is enhanced due to the different dyes' molecular structures and/or aggregations on the surface of LDH with various morphological patterns. The combined NF-LDH/dye composite LB film photoelectrode can generate a photocurrent that is 2−5 times stronger than the raw material, and the stable use efficiency is more than 92%. Present obtained composite LB films demonstrated a uniform morphology and good photoelectric conversion ability. This work provides a useful reference for the field of LDH semiconductor optoelectronic devices and solar cells.

Self-Assembled Black Phosphorus-Based Composite Langmuir–Blodgett Films with an Enhanced Photocurrent Generation Capability and Surface-Enhanced Raman Scattering Properties

“…Then, the oxidized electrolyte diffuses into a Ce to regenerate electrons, thereby generating current. 31 The transient photocurrent response of the thin film anode over time was recorded by time amperometry (the light on/off period is 30 s) and is shown in Figure 8a. Anode photocurrent increases when lighting starts and decreases when lighting stops.…”

“…Since the potential of the electrolyte electron pair is lower than the redox potential of the dye, the dye molecules in the oxidized state are easily reduced by the electrolyte in the reduced state. Then, the oxidized electrolyte diffuses into a Ce to regenerate electrons, thereby generating current . The transient photocurrent response of the thin film anode over time was recorded by time amperometry (the light on/off period is 30 s) and is shown in Figure a.…”

Construction of Multifunctional and Adjustable Langmuir–Blodgett Composite Films Containing Black Phosphorus with High Stability for Optically Electrical Applications

“…Moreover, the composite film prepared using the LB technology can save materials and realize recycling due to its good stability. In the previous work, the hydrotalcite-based composite film obtained using the LB technique showed good stability in the repeated test of the photocurrent response . Furthermore, large-area stable monolayer molecular films can be assembled through the LB film technology, which is widely used in the assembly of nanoparticles and nanosheets, and the density and spacing of nanoparticles can be precisely controlled to construct monolayer and multilayer films.…”

A study of the possibility of conducting selective laser processing of thin composite electrochromic Ni(OH)2-PVA films

“…Thin films of nickel hydroxide have also found application in solar cells [14,15]. This application is due to the fact that NiOOH (as well as NiO) can be easily obtained from Ni(OH) 2 and is a p-type semiconductor [16].…”