Photosensitive Thin Films Based on Drop Cast and Langmuir-Blodgett Hydrophilic and Hydrophobic CdS Nanoparticles

Abstract

Comparative photoelectrochemical studies of cadmium sulfide (CdS) nanoparticles with either hydrophilic or hydrophobic surface properties are presented. Oleylamine organic shells provided CdS nanoparticles with hydrophobic behavior, affecting the photoelectrochemical properties of such nanostructured semiconductor. Hydrophilic CdS nanoparticles were drop-cast on the electrode, whereas the hydrophobic ones were transferred in a controlled manner with Langmuir-Blodgett technique. The substantial hindrance of photopotential and photocurrent was observed for L-B CdS films as compared to the hydrophilic, uncoated nanoparticles that were drop-cast directly on the electrode surface. The electron lifetime in both hydrophilic and hydrophobic nanocrystalline CdS was determined, revealing longer carrier lifetime for oleylamine coated CdS nanoparticles, ascribed to the trapping of charge at the interface of the organic shell/CdS nanoparticle and to the dominant influence of the resistance of the organic shell against the flux of charges. The “on” transients of the photocurrent responses, observed only for the oleylamine-coated nanoparticles, were resolved, yielding the potential-dependent rate constants of the redox processes occurring at the interface.

Green composites based on volcanic red algae Cyanidiales, cellulose, and coffee waste biomass modified with magnetic nanoparticles for the removal of methylene blue

“…Despite many commonly used water treatment techniques, innovative, cost-effective methods are still deeply needed. Effective wastewater treatment can be performed with many different techniques, including membrane separation (Li 2014 ; Wu et al 2012 ), adsorption (Boi 2016 ; Nadour et al 2019 ; Shao et al 2008 ; Phuong et al 2022 ; Olusegun et al 2023a , b ), photocatalytic oxidation (Rezaei et al 2021 ), electrochemical methods (Alnajrani and Alsager 2020 ; Spaltro et al 2020 ), biopolymer sorption (Zhou et al 2016 ; Zhou et al 2017a , b ), photodegradation (Hussain et al 2020 ; López Zavala and Espinoza Estrada 2016 , Nagamine et al 2020 , Olusegun et al 2023b ), biosorption (Zhou et al 2019 ), and biodegradation (Wang et al 2020 ). Among them, adsorption-based processes are considered the most effective, also offering cost-effectiveness, simplicity of preparation, and high customizability (Rashed 2013 ).…”

Times effect on morphological, structural and optical behaviors of cds thin films for photoelectrochemical cells application

“…It provides information about the density of donors or acceptors, NA and ND are the acceptor and donor concentration of p-type and n-type semiconductors, as well as the potential of the band flat (Efb). It is based on the measurement of capacitance of the space charge of semiconductor layer as a function of potential (C -2 vs. E) according to the following relation[40,41]:…”