Sustainable high-entropy materials?

Area of Science:

• Materials Science
• Sustainable Engineering
• Solid-State Chemistry

Background:

• High-entropy materials (HEMs) exhibit remarkable properties owing to their complex multi-elemental compositions.
• Current HEM production methods are often energy-intensive, costly, and environmentally burdensome.
• Recycling HEMs is difficult due to their reliance on expensive, limited elements in precise compositions.

Purpose of the Study:

• To review the fundamental sustainability challenges associated with high-entropy materials.
• To propose viable strategies for enhancing the environmental compatibility of HEMs throughout their lifecycle.
• To identify pathways for reconciling desirable material properties with sustainable manufacturing and recycling.

Main Methods:

• Literature review focusing on sustainability aspects of HEMs.
• Analysis of alternative feedstock sources, including minerals and waste materials.
• Exploration of thermodynamic and kinetic design principles for impurity tolerance.

Main Results:

• HEMs' inherent properties like high solubility and compositional flexibility facilitate the use of lower-grade and mixed-waste feedstocks.
• Sustainable synthesis routes from minerals and adaptation of the equimolar rule are viable alternatives.
• Design strategies can enable the use of contaminated scrap and waste for secondary and tertiary synthesis.

Conclusions:

• Adopting sustainable feedstock and synthesis routes is crucial for the widespread adoption of HEMs.
• HEMs' unique characteristics provide opportunities for circular economy approaches, utilizing waste streams effectively.
• Further research into thermodynamic and kinetic design can optimize HEMs for both performance and sustainability.