Single-source mediated facile electrosynthesis of p-Cu₂S thin films on TCO (SnO₂:F) with enhanced photocatalytic activities

Abstract

Electrosynthesis of p-Cu 2 S thin films on a fluorine-doped tin oxide coated transparent conducting TCO (SnO 2 :F) glass substrate is carried out by chronoamperometry and cyclic voltammetry (CV) using an ethanolic solution of a single-source precursor (SP), [Cu(mdpa) 2 ][CuCl 2 ] (where mdpa is 3,5-dimethyl pyrazole-1-dithioic acid). The appropriate potential at which the formation of stoichiometric p-Cu 2 S thin films occurs was found to be À0.48 V. The mechanism of the selective deposition of the p-Cu 2 S phase can be described by the electroreduction of Cu-N/S bonds in the coordination sphere following the dissociation of a precursor complex into Cu + and mdpa. The free ligand mdpa is reduced to sulfide ion producing volatile organics in the electrochemical process. The quality deposition of thin films depends on the optimization of the SP concentration. An X-ray diffraction study reveals the high chalcosite phase of copper sulfide with preferential orientation along the (110) plane. The I-V characteristic of the as deposited Cu 2 S/TCO thin film shows a non-ohmic behavior suggesting the formation of a p-n heterojunction diode. The p-Cu 2 S/TCO thin films are found to be excellent photocatalysts for the photo-degradation of Congo Red (CR) under visible light irradiation. It has also been shown that the photocatalytic activity of the deposited thin films increased many fold with the addition of a catalytic amount of hydrogen peroxide in the photo-degradation of Rose Bengal (RB) dye under visible light irradiation. A possible mechanism for the improved photoactivity of p-Cu 2 S/TCO is proposed and involves the electron scavenging property of H 2 O 2 followed by OH À radical formation, significantly accelerating the photodegradation of RB dye.

Development of Bi2S3/Cu2S hetrojuction as an effective photocatalysts for the efficient degradation of antibiotic drug and organic dye

“…In Fig. 1 , the observed diffraction peaks can be attributed to a pure Cu 2 S cubic structure with (1 1 1), (2 0 0), (220), (3 1 1), and (2 2 2) planes corresponding to 2 theta value of 29.01°, 31, 76°, 46.05°, 52.44°, and 57.10° in good agreement with (JCPDS #84-1770) (Mondal et al 2015 ). X-ray diffraction patterns of Bi 2 S 3 /Cu 2 S nanocomposites show the presence of both Bi 2 S 3 and Cu 2 S, which confirms the presence of the composite.…”

Effects of surfactant and reaction time on the formation and photocatalytic performance of Cu2S thin films grown in situ on Cu foil by hydrothermal method

“…For p-Cu 2 S thin films on a fluorine-doped, tin oxide-coated, transparent conducting TCO glass substrate by electrosynthesis, the percent degrade after 90 minutes was 90 [16]. Despite all this, the Cu 2 S thin films are expected to be cheaper in manufacture including low materials cost and energy consumption.…”

Monomeric and dimeric cadmium(II) complexes of S-alkyl/aryl dithiocarbazate as single-source precursors for cadmium sulfide nanoparticles: An experimental, theoretical interpretation in the stability of precursor and visible light dye degradation study

“…The tuning of size and shape of the nanoparticles can be controlled by the intrinsic structural properties of SP [8,9] in the solvothermal decomposition method. S-Methyl/benzyl dithiocarbazates have been successfully utilized earlier by us to synthesize binary CuS [10,6], PbS [11,12] and CdS [13][14][15] and ternary CuInS 2 [16,17] nanoparticles with various morphologies. In order to study the effect of N-heterocycle rings such as pyridine etc.…”