Synthesis, Electronic and Optical Properties of Cobalt(II) Dithiocarbamate Fluorescent Nanowires for Optoelectronic Devices

Abstract

Schiff base containing symmetric bis-dithiocarbamate ligand Na 2 [dtc-SB-dtc] (SB = Bi-Schiff base Phenylene diamine) is synthesized and metallated with Co(II)Cl 2 .6H 2 O to form [Co(dtc-SB-dtc).2H 2 O] n Co(dtc-SB) infinite coordination polymer (ICP) nanowires [Co(dtc-SB) NWs]. Pair of Satellites in X-ray photoelectron spectroscopy (XPS) spectrum of Co 2p confirm the formation of hexa-coordinated Co(II). Presence of hyperfine pattern in low temperature EPR spectrum is due to the splitting of octahedral ground state 4 T 1 for Co(II). Introduction of a rigid, non-planar, four membered dtc Cobalt chelating ring in coordination polymer assisted in reduction of photoinduced electron transfer (PET) process to yield high fluorescence. Prepared Co(dtc-SB) NWs are highly resistive however after suitable doping, exhibit p and n type conductivity. Temperature dependent conductivity results of different doping concentrations in NWs reflect activated type conduction with two different activation energies. UV-Visible absorption spectra show decrement in optical gap whereas emission spectra demonstrate quenching after p and n doping. Efficient quenching of emission indicates energy transfer between dopant ions and NWs.

Facile preparation of graphene nanoribbon/cobalt coordination polymer nanohybrid for non-enzymatic H2O2 sensing by dual transduction: electrochemical and fluorescence

“…The solution dispersability of MCPs@GNR is studied using concentration dependence UV-Vis absorption spectroscopy. Peak at 531.3 eV in O 1s spectra ( Figure 2d) indicates the presence of Co-O-H in the structure which is consistent to literature [40,46]. Interestingly, the band intensity has shown small quenching on composite formation confirming efficient charge-transfer processes [43].…”

“…2d) indicates the presence of Co-O-H in the structure which is consistent with the literature. 40,46 Another peak at 532.9 eV in the O 1s spectra shows correlation with the peak at 168.3 eV in the S 2p XPS spectrum; which originates from oxidised sulphur 47 as shown in Fig. 2e.…”

“…Dithiocarbamate ligand (dtc-SB) with the molecular formula C 16 H 12 N 4 Na 2 S 4 was used for synthesizing MCPs and was prepared in two steps as described previously. 40 Here, we have used the anionic surfactant sodium sulfosuccinate (commonly known as AOT), to form reverse micelles which act as ''reactors'' for performing reactions leading to nanoparticles formation. When dissolved in organic solvent (DMF), AOT forms thermodynamically stable spherical aggregates having hydrophilic head groups inside and hydrophobic tails extending into a nonpolar medium (isooctane).…”

“…MCPs functionalized graphene nanoribbon (MCPs@GNR) designed for hydrogen peroxide detection possesses dual functions including catalytic ability due to Co atoms and fluorescence as a result of ligand to metal charge transfer (LMCT). 40 The black color colloidal suspension of MCPs@GNR in PBS emits intense fluorescence, l em. max = 494 nm under UV light excitation of 365 nm.…”

Polycrystalline Compound of Co2+-doped Zn2SnO4: Structural and Photoluminescent Properties

“…Co 2+ ions present interesting optical properties in different materials, as can be seen in the following examples. Dithiocarbamate nanowires containing Co(II) present an emission band from 455 to 526 nm due to the hexa-coordinated Co(II) 18 . Additionally, Zn 2 SiO 4 :Co 2+ presents a blue emission (peaks at 420 and 480 nm) and green emission (at 525 nm), showing a potential for use as blue and green phosphors for luminescent systems 19 .…”