Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socio-economic development. To that goal, hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting, if driven by green electricity, would provide hydrogen with minimal CO2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research, also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness first-principles calculations and machine learning. In addition, a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the ‘junctions’ between the field's physical chemists, materials scientists and engineers, as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains.

Water electrolysis: from textbook knowledge to the latest scientific strategies and industrial developments

Hydrogen gas obtained by the electrolysis of water has long been proposed as a clean and sustainable alternative to fossil fuels. Noble metals such as Pt are capable of splitting water at low overpotentials, but the implementation of inexpensive solar-driven water-splitting systems and electrolyzers could benefit from the development of robust, efficient, and abundant alternatives to noble metal catalysts. Transition metal phosphides (MxPy) have recently been identified as a promising family of Earth abundant electrocatalysts for the hydrogen-evolution reaction (HER) and are capable of operating with low overpotentials at operationally relevant current densities while exhibiting stability under strongly acidic conditions. In this review, we highlight the progress that has been made in this field and provide insights into the synthesis, characterization, and electrochemical behavior of transition metal phosphides as HER electrocatalysts. We also discuss strategies for the incorporation of metal phosphides ...

Synthesis, Characterization, and Properties of Metal Phosphide Catalysts for the Hydrogen-Evolution Reaction

Nickel phosphide, nickel selenide thin films and their heterostructure (Ni0.85Se/Ni2P) were deposited from a newly synthesized single source precursor {Ni[iPr2P(S)NP(Se)iPr2]2} just by altering the deposition temperature using CVD.

The chemical vapor deposition of nickel phosphide or selenide thin films from a single precursor

Nonalloyed ohmic contacts of Pt/Ti to 5×1018 cm−3 doped p‐InGaAsP (λg =1.3 μm) have been fabricated by rapid thermal processing of sputtered and e‐gun‐deposited metallizations. While the former as‐deposited had a rectifying characteristic, the latter showed ohmic behavior prior to any heat treatment, with a specific contact resistance of 4×10−3 Ω cm2. Rapid thermal processing at temperatures higher than 400 °C caused the formation of ohmic contacts for the sputtered metals also, but with the evaporated metals producing slightly lower contact resistance. The lowest specific contact resistance values of 3.6–5.5×10−4 Ω cm2 for evaporated and sputtered metallizations, respectively, were achieved in both cases as a result of heating at 450 °C for 30 s. These heating conditions produced only a limited reaction at the Ti/InGaAsP interface, which was sharper for the e‐gun‐deposited contact, but had a significant effect on the stresses in the Ti/Pt bilayer. In both the sputtered and electron gun evaporated samples...

Pt/Ti/p‐InGaAsP nonalloyed ohmic contact formed by rapid thermal processing

The relationship between the electrical properties and microstructure for annealed Au/Ge/Ni contacts to n-type InP, with an initial doping level of 1017 cm-3, have been studied. Metal layers were deposited by electron beam evaporation in the following sequence: 25 nm Ni, 50 nm Ge, and 40 nm Au. Annealing was done in a nitrogen atmosphere at 250-400‡C. The onset of ohmic behavior at 325‡C corresponded to the decomposition of a ternary Ni-In-P phase at the InP surface and the subsequent formation of Ni2P plus Au10In3, producing a lower barrier height at the InP interface. This reaction was driven by the inward diffusion of Au and outward diffusion of In. Further annealing, up to 400‡C, resulted in a decrease in contact resistance, which corresponded to the formation of NiP and Au9ln4 from Ni2P and Au10In3,respectively, with some Ge doping of InP also likely. A minimum contact resistance of 10-7 Ω-cm2 was achieved with a 10 s anneal at 400‡C.

Au/Ge/Ni ohmic contacts to n-type InP

Ni 2 P is a metallic conductor with a bulk resistivity of 32 µΩ . cm. Films of Ni 2 P can be sputter-deposited in both the amorphous and crystalline forms by varying the sputtering parameters. The amorphous to crystalline transition has been found to take place at about 250 °C and sufficient grain growth to exhibit X-ray reflections takes place by 400 °C. In both forms, films of Ni 2 P have been found to form ohmic contacts to n-InP (Sn doped 2 × 1018cm-3) p-InGaAs (Zn-doped 8 × 1018cm-3) with sufficiently low sheet resistivity and specific contact resistance to be useful as a metallization layer in most devices. It was also found that up to 400 °C, amorphous (as sputtered) films of Ni 2 P function as efficient diffusion barriers between an outer Au layer and the III-V substrate. It is possible, therefore, for amorphous (as sputtered) films of Ni 2 P to function simultaneously both as a metallization layer and diffusion barrier.

VIA-7 sputter Ni-P as an ohmic contact to n-InP, p-InGaAs and as a diffusion barrier

Structure of sputtered Ni2P films

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

F. Schrey

Author Tools

Chat about Author

Papers

VIA-7 sputter Ni-P as an ohmic contact to n-InP, p-InGaAs and as a diffusion barrier

Structure of sputtered Ni2P films