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To solve energy crisis, the engineering of highly efficient and cost-effective photoanodes is urgently required for clean fuel generation. Herein, CdSe(en)0.5 (en = ethylenediamine) hybrid photoanodes were synthesized by a solvothermal approach. It was revealed that a second in situ hydrothermal treatment successfully converts cadmium foil-based inorganic-organic CdSe(en)0.5 (en = ethylenediamine) hybrid nanosheets to an oriented cadmium hydroxide crowned CdSe nanowire-decorated porous nanosheet (Cd(OH)2/CdSe NW/NS) heterostructure by dissolution and regrowth mechanisms. The alteration in second hydrothermal reaction conditions could modify the morphology and optical properties of the Cd(OH)2/CdSe NW/NS heterostructure photoanodes. The possible growth mechanism of the Cd(OH)2/CdSe NW/NS porous structure is studied at various second hydrothermal times using the control experiments of the synthesis. The optimized 3D porous Cd(OH)2/CdSe NW/NS photoanodes exhibited an outstanding photocurrent density of 6.1 mA cm-2 at 0 V vs. Ag/AgCl, which is approximately 7.6 times higher than that of the inorganic-organic CdSe(en)0.5 hybrid under light irradiation (>420 nm cut off filter). A mechanism is proposed to explain the enhanced charge separation at the Cd(OH)2/CdSe NW/NS photoanode/electrolyte interface, which is supported by PL and photoelectrochemical analyses. These findings open an avenue of phase and morphology transmutation for efficient formation of other hierarchical structures of metal selenides and sulfides. Additionally, the Al2O3 co-catalyst can act as effective hole trapping sites and improves the stability of the photoelectrode through the timely consumption of photogenerated charges, particularly holes.

We use the reaction–diffusion framework (RDF) to study the kinetics of formation of hierarchical microstructures of cadmium–aluminum layered double hydroxide (CdAlCl LDH), its particle size distribution, and its polymorphic transformation to brucite-like cadmium hydroxide (β-Cd(OH)2). The system exhibits the evolution of two successive bands separated by a sharp interface, a leading one that constitutes the yellow CdAlCl LDH followed by the white brucite band. We show that by using the RDF we can manipulate the size distribution of the particles within the LDH band along the tubular reactor. The spatiotemporal dynamics of these bands provides a simple means to study the kinetics of formation of the LDH and its polymorphic transformation as a function of the cationic ratio, hence predicting its stability. Consequently, the relative rate constants and the Avrami exponents are calculated and are shown to exhibit a linear correlation with the cationic ratio. The collapse of the LDH microstructures into nano-spheroids of β-Cd(OH)2 is visualized using scanning electron microscopy at the LDH–brucite interface.

Herein, we report a novel high-dimensional I3O3 organic–inorganic hybrid framework, namely [Cd3(OH)2(tza)2]n (1) (H2tza = 1H-tetrazolate-5-acetic acid), where a rare pure ths inorganic connectivity of Cd–Ohydroxyl is observed. Meanwhile, 1 displays blue emission and high thermal stability up to 370 °C.

Cadmium hydroxide [Cd(OH)2] nanowires have been successfully synthesized by a simple chemical bath deposition method (CBD) on a stainless-steel (SS) substrate. By scanning electron microscopy (SEM), the surface architecture displays the formation of bundles of high-surface-area nanowires (NWs), which are beneficial for supercapacitor applications. Cd(OH)2 NWs on SS has been tested as an electrode material for supercapacitor applications via electrochemical studies by cyclic voltammetry, charge–discharge and electrochemical impedance spectroscopy techniques in an aqueous electrolyte. Electrochemical data confirm that Cd(OH)2 NWs thin-film electrode exhibits supercapacitor behavior, having a yield of 267 F g−1 specific capacitance at 5 mV s−1 scan rate with excellent cycling life (86% capacitance retention over 1000 cycles). A Cd(OH)2/Cd(OH)2 symmetric supercapacitor device provides a maximum energy density of 11.09 W h kg−1 and a power density of 799 W kg−1 at a current density of 0.84 A g−1. The present work demonstrates that Cd(OH)2 NWs thin film is a promising, low-cost alternative material prepared by a simple, binder-free chemical bath deposition method (CBD) for supercapacitor applications.

Treatment of the ebnpa (N-2-(ethylthio)ethyl-N,N-bis((6-neopentylamino-2-pyridyl)methyl)amine) ligand with a molar equivalent amount of Cd(ClO(4))(2).5H(2)O in CH(3)CN followed by the addition of [Me(4)N]OH.5H(2)O yielded the cadmium hydroxide complex [(ebnpaCd)(2)(mu-OH)(2)](ClO(4))(2) (1). Complex 1 has a binuclear cation in the solid-state with secondary hydrogen-bonding and CH/pi interactions involving the ebnpa ligand. In acetonitrile, 1 forms a binuclear/mononuclear equilibrium mixture. The formation of a mononuclear species has been confirmed by conductance measurements of 1 at low concentrations. Variable temperature studies of the binuclear/mononuclear equilibrium provided the standard enthalpy and entropy associated with the formation of the monomer as DeltaH degrees = +31(2) kJ mol(-1) and DeltaS degrees = +108(8) J mol(-1) K(-1), respectively. Enhanced secondary hydrogen-bonding interactions involving the terminal Cd-OH moiety may help to stabilize the mononuclear complex. Treatment of 1 with CO(2) in acetonitrile results in the formation of a binuclear cadmium carbonate complex, [(ebnpaCd)(2)(mu-CO(3))](ClO(4))(2) (2).

Cd(OH)2 nanowire anode materials without memory effect were prepared, which had also excellent capacity and stability and reduced at least 80% discharging of toxic heavy metal Cd pollutant to environment under identical capacity conditions.

The integration of fluorescent inorganic nanocrystals into hybrid thin films with desirable optoelectronic properties is strongly demanded for their applications. We prepared flexible free-standing ultrathin protein films containing fluorescent nanocrystals by means of a filtration technique assisted by metal hydroxide nanostrands with high aspect ratio and extremely high positive charges on the surfaces. First, negatively charged proteins (apoferritin), CdSxSe1−x/ZnS nanocrystals (and/or fluorescent dye) were assembled on the surfaces of cadmium hydroxide nanostrands in water through electrostatic interaction. The resultant dispersion of nanocomposite fibers was filtered on a porous membrane to give a thin filter cake. After cross-linking apoferritin, the nanostrands were removed, and the remaining protein/nanocrystal composite layer was peeled off from the substrate in ethanol as a free-standing fluorescent film. The film thickness could be as thin as 40 nm, without limitation in the diameter. The free-standing fluorescent films are robust enough to be transferred onto any solid substrate without rupturing. The fluorescent films with different colors were obtainable by choosing fluorescent nanocrystals (and/or fluorescent dye) to be immobilized into the protein matrix. The optical properties of these films were changed with the combination of the nanocrystals and fluorescent dye, and the fluorescent resonance energy transfer quenching (or enhancement) was clearly observed in certain conditions. The amount of CdSxSe1−x/ZnS nanocrystals in the film was as high as 41% in weight, and 13% in volume. The fluorescent film was transparent and without obvious segregation of the nanocrystals, as confirmed by high-resolution transmission electron microscope (HR-TEM). The fluorescent emission was bright, uniform, and as narrow as that in the original solution of the nanocrystals. This is remarkable for the application of fluorescent inorganic nanocrystals to flexible solid optical devices.

A novel binuclear cadmium hydroxide complex has been isolated, structurally and spectroscopically characterized, and has been shown to undergo reaction with CO2 to yield a binuclear cadmium carbonate complex.

Cadmium sulphate reacts at 440 °C in pure lithium nitrate–potassium nitrate eutectic, but at much lower temperatures when Lux–Flood bases (Na2O2, Na2O, and Na[OH]) are present, in accord with the relative availability of oxide ions. The product is cadmium oxide, except in the presence of moisture or hydroxide when cadmium hydroxide is formed preferentially. Cadmium oxide does not catalyse decomposition of the melt, and there is no evidence for the formation of anionic cadmate species.

Conditions of deposition of cadmium from cadmium perchlorate solutions on copper electrodes, leading to the appearance of granular deposit (boulders), have been investigated. It was found that this type of deposit appears in a limited pH range only (pH 3 to 6) in which colloidal cadmium hydroxide is found to appear. The probability of appearance of granules is different at different crystal planes of the copper substrate. The rate of growth of the granules has been determined microscopically. It was found that the size of the granules increases proportionally to the square root of time. This indicates that the rate of growth is controlled by the spherical diffusion of depositing ions from the bulk of solution.