Producing white light using near-UV LEDs requires the development of new phosphors, as well as the modification of certain existing ones. In this review, we discuss the luminescent properties of potential phosphors: oxides, silicates, phosphates and nitrides. We evaluate phosphors that employ 4f-5d transitions, line emission, the use of sensitizers and transition metal elements. We include information on the optical transitions and how these can limit the selection of a composition.

Thin films of normalNiCo and normalCoFe have been galvanostatically electroplated onto a platinum rotating disk electrode from simple sulfate baths containing 0.5M of the more noble metal sulfate and 0.1M of the less noble metal sulfate. The experimental results are compared to those of previous studies of normalNiFe codeposition in order to study the anomalous codeposition behavior of the binary iron‐group alloys. Comparison of the electrodeposition results indicates that codeposition of these binary alloys is not totally analogous. It was found that codepositions of normalNiCo and normalNiFe show more mass‐transfer effects than does normalCoFe deposition within the range of current densities studied. A model of anomalous codeposition put forth previously for normalNiFe was applied to the electrodeposition of normalNiCo and normalCoFe to determine the extensibility of the model, which assumes metal monohydroxides, MOH+ , are the important charge‐transfer species. This model was unable to characterize fully either normalNiCo or normalCoFe electrodeposition. However, with minor changes to the hydrolysis constants used in the model, the model predictions were found to agree with the data for normalCoFe codeposition and greatly improve the fit for the normalNiCo results.

A mathematical model is developed to simulate the electrodeposition of the nickel‐iron alloy from simple sulfate solutions. Equilibrium calculations indicate the importance of the metal monohydroxide species in the codeposition mechanism. A one‐dimensional diffusion model of the codeposition is developed and agrees well with experimental results for different bath compositions and operating conditions. The sensitivity of the model is evaluated and a mechanism for the anomalous codeposition of nickel‐iron is proposed.

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