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14.8% Quantum Efficient Gallium Phosphide Photocatalyst for Hydrogen Evolution
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Coupling Amorphization and Compositional Optimization of Ternary Metal Phosphides toward High-Performance Electrocatalytic Hydrogen Production
Amorphous materials, with abundant active sites and unique electronic configurations, have the potential to outperform their crystalline counterparts in high-performance catalysis for clean energy. However, their synthesis and compositional optimization remain underexplored due to the strict conditions required for their formation. Here, in this study, we report the synthesis of ternary platinum-nickel-phosphorus (PtNiP) amorphous nanoparticles (ANPs) within milliseconds by flash Joule heating, which features ultrafast cooling that enables the vitrification of metal precursors. Through compositional optimization, the Gibbs free energy of hydrogen adsorption for Pt 4 Ni 4 P 1 ANPs is optimized at 0.02 eV, an almost ideal value, even surpassing that of the benchmark metallic platinum catalyst. As a result, the PtNiP ANPs exhibited superior activity in electrocatalytic hydrogen evolution in acid electrolyte (η 10 ∼ 14 mV, Tafel slope ∼ 18 mV dec –1 , and mass activity 5× higher than state-of-the-art Pt/C). Life-cycle assessment and technoeconomic analysis suggest that, compared to existing processes, our approach enables notable reductions in greenhouse gas emission, energy consumption, and production cost for practical electrolyzer catalyst manufacturing.
Single Crystal Growth of Synthetic Sulfide- and Phosphide-Based Minerals for Physical Measurements
In this work, we review recent advances in the use of high-temperature solution growth that allow for the growth of single crystalline samples of synthetic minerals. We outline how low-melting binary or ternary solutions are attractive solvents for solution growth and provide examples of the growth of bismuthinite (Bi 2 S 3 ), galena (PbS) and parkerite (Ni 3 Bi 2 S 2 ). We then focus on the Rh-S, Pd-S and Ni-P phase spaces to discuss how the low-melting regions near transition metal-main group eutectic compositions make excellent solvents for crystal growth of several binary and ternary minerals containing both high melting and volatile elements as well as for the discovery of new materials. We end by discussing the growth of synthetic canfieldite (Ag 8 SnS 6 ) and argyrodite (Ag 8 GeS 6 ) from Ag 2 S–Sn-S-based solutions.
Efficiency of a gallium arsenide phosphide solar cell at high light intensities.
Conversion efficiency of GaAs solar cell at various light intensities
Fundamental studies of the metallurgical, electrical, and optical properties of gallium phosphide Quarterly progress report, 1 Jul. - 30 Sep. 1968
Schottky barrier diode performance tests, Be doping of GaP, and S, Se, and Te diffusion into GaAs
Absorption spectrum of nickel in gallium phosphide.
Optical absorption spectra of Ni impurity in GaP due to d shell transitions, measuring crystal field parameters, noting fine structure
Zinc diffusion into gallium phosphide under high and low phosphorus overpressure.
Depth and planarity of zinc diffused junctions in GaP using temperature, phosphorus overpressure and time as independent variables
Gallium phosphide devices for use at high temperatures.
Schottky barrier diodes for high temperature operation prepared on n type GaP single crystals, studying I-V and C-V characteristics
The formation of phosphides in iron meteorites.
Fe-Ni-P phase diagram studies applied to schreibersite and rhabdite formation in iron meteorites
High temperature gallium phosphide rectifiers
Development of high reverse breakdown voltage and low forward voltage drop stability in high power Schottky GaP rectifier for high temperature application is reported.
Development of high temperature gallium phosphide rectifiers
Large area high performance, GaP rectifiers were fabricated by means of Zn diffusion into vapor phase epitaxial GaP. Devices with an active area of 0.01 sq cm typically exhibit forward voltages of 3 volts for a bias current of 1 ampere and have reverse breakdown voltages of 300 volts for temperatures from 27 C to 400 C. Typical device reverse saturation current at a reverse bias of 150 volts is less than 10 to the minus 9th power amp at 27 C and less than 0.000050 amp at 400 C.
Photodetachment of electrons from phosphide ion - The electron affinity of PH2.
Measurement of the relative cross section for photodetachment of electrons from PH2(-) in the wavelength region 725 to 1020 nm (1.71 to 1.22 eV). An ion cyclotron resonance spectrometer was used to generate, trap, and detect the negative ions, and two light sources were employed to study photodetachment: a 1000-W xenon arc lamp with a grating monochromator and a continuously tunable laser. A single sharp threshold in the cross-section curve was observed, and a detailed analysis yielded an electron affinity value of 1.25 plus or minus 0.03 eV.
The growth and electrical characteristics of epitaxial layers of zinc sulphide and of zinc selenide on p-type gallium phosphide.
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Ohmic contact to p-type indium phosphide
Low-Series-resistance ohmic contact to p-type InP semiconductor material is achieved in technique utilizing Au-Ge-Zn eutectic alloy. Alloy sets and adheres well to semiconductor surface with higher acceptor concentration at metal semiconductor interface. Technique has provided satisfactory for pn junction LED's and lasers.
A study to investigate the chemical stability of gallium phosphate oxide/gallium arsenide phosphide
The elemental composition with depth into the oxide films was examined using secondary ion mass spectrometry. Results indicate that the layers are arsenic-deficient through the bulk of the oxide and arsenic-rich near both the oxide surface and the oxide-semiconductor interface region. Phosphorus is incorporated into the oxide in an approximately uniform manner. The MIS capacitor structures exhibited deep-depletion characteristics and hysteresis indicative of electron trapping at the oxide-semiconductor interface. Post-oxidation annealing of the films in argon or nitrogen generally results in slightly increased dielectric leakage currents and decreased C-V hysteresis effects, and is associated with arsenic loss at the oxide surface. The results of bias-temperature stress experiments indicate that the major instability effects are due to changes in the electron trapping behavior. No changes were observed in the elemental profiles following electrical stressing, indicating that the grown films are chemically stable under device operating conditions.
Characterization of n-type semiconducting indium phosphide photoelectrodes Stabilization to photoanodic dissolution in aqueous solutions of telluride and ditelluride ions
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