Stable Core/Shell CdTe/Mn-CdS Quantum Dots Sensitized Three-Dimensional, Macroporous ZnO Nanosheet Photoelectrode and Their Photoelectrochemical Properties

Abstract

A novel photoelectrode based on ZnS/CdTe/Mn-CdS/ZnS-sensitized three-dimensional macroporous ZnO nanosheet (NS) has been prepared by electrodeposition and successive ion layer adsorption and reaction (SILAR) method. The photoelectrode performances were significantly improved through the coupling of the core/shell CdTe/Mn-CdS quantum dots (QDs) with ZnO NS, and the introduction of the ZnS layer as a potential barrier. The photocurrent density systematically increases from ZnO NS (0.45 mA/cm(2)), CdTe/Mn-CdS/ZnO NS (4.98 mA/cm(2)), to ZnS/CdTe/Mn-CdS/ZnS/ZnO (6.23 mA/cm(2)) under the irradiation of AM 1.5G simulated sunlight. More important, the ZnS/CdTe/Mn-CdS/ZnS-sensitized ZnO NS photoelectrode provides a remarkable photoelectrochemical cell efficiency of 4.20% at -0.39 V vs Ag/AgCl.

Photoelectrochemical Immunosensor for Detection of Carcinoembryonic Antigen Based on 2D TiO2 Nanosheets and Carboxylated Graphitic Carbon Nitride

“…Therefore, photoactive materials are crucial for the performance of the PEC sensors. Many photoactive materials are metal-contained semiconductors, such as TiO 2 , CdSe, CdTe, ZnO, ZnS, etc123456789. Among them, titanium dioxide is one of the most commonly employed materials because of its nontoxicity, low-cost and brilliant photochemical and chemical stability.…”

Photoelectrochemical detection of alpha-fetoprotein based on ZnO inverse opals structure electrodes modified by Ag2S nanoparticles

“…Furthermore, its excellent thermal, chemical, low density, good biological compatibility and excellent photochemical stability3031 make it attractive in PEC bioanalysis3233. Many ZnO nanostructures, such as nanorods29, nanotubes34, nanowires11, nanosheets35 and nanoflowers36, have been applied in biosensor. Despite of this, the usage of ZnO without modification in PEC-based bioanalysis has some limitations because of its inherent wide band gap which results in a strong absorption in the UV region.…”

Fabrication of high-performance CuInSe2 nanocrystals-modified TiO2 NTs for photocatalytic degradation applications

“…The formed • OH was detected with a terephthalic acid fluorescence probe under excitation of 320 nm with a scanning speed of 1200 nm/min and both the excitation slit and emission slit widths of 5.0 nm. Terephthalic acid can quickly react with • OH to generate 2-hydroxyterephthalic acid, whose fluorescence intensity is proportional to the amount of • OH [35,55]. As shown in Fig.…”

“…Electrons accumulated on the surface of CuInSe 2 are scavenged by dissolved oxygen molecules to yield superoxide radical anion • O 2 − , producing hydroxyl radical (•OH) (Eqs. (3)-(4)) [35,52]. At the same time, the holes in CuInSe 2 can potentially react with water or OH − , adhering to the surface of the photoelectrode to form highly reactive • OH radicals (Eq.…”

“…These SEM images clearly show that the nanoparticles with an average particle size of 88 nm are homogeneously coated on the TiO 2 NTs no matter 30 or 80 L CuInSe 2 NCs are coated. The CuInSe 2 NCs does not obviously change the macroporous morphology of the TiO 2 NTs[35], which is vital for the incident light absorption which results in excellent photoelectrochemistry performance.The XRD pattern ofFig. 1(D)shows that the CuInSe 2 NCs are with tetragonal chalcopyrite crystal structure.…”