On Materials Science and Engineering in Energy

Solar tower concentrates light reflected from surrounding panels.  (Source: Paul Langrock/Zenit/Laif/Redux)

A thoroughly interesting report [1] has recently been published regarding the future of materials science and engineering in energy and related fields.  The report is available on-line here; and it is also summarized in the latest issue of the Journal of Minerals, Metals, and Materials (JOM) [2].  The report is written well and with the general public in mind; for the hobby scientist, it also helps convey a thought-provoking state-of-the-art in materials science and engineering.  To summarize the already-summarized article in JOM, the topics in the report - and subjects which will be in the forefront of future materials study - are:

Functional Surface Technology (or: making the surfaces of materials perform in new/different/improved ways).  This includes:

• Catalysts with high selectivity and conversion efficiency.  When catalysts aren't efficient, energy is wasted.
• Smart coating / lubricant systems for lightweight alloys.  Lighter alloys such as aluminum and magnesium tend to wear down relatively quickly. 
• Coatings to inhibit galvanic corrosion.  Corroded materials' performance rapidly degrades.
• Solar photovoltaic materials utilizing a broader spectrum of light.  Current solar panels only collect a fraction of the light energy available.
• Treatment processes to rebuild or enhance surfaces.  Materials' recycle-ability, re-use, and service life can all extended.
• High flux membranes for selective separation of atmospheric gases.  Capture of carbon dioxide emissions, for example, can be made more efficient and scalable to industrial levels.    

Higher-Performance Materials for Extreme Environments.  This includes:

• High-temperature, phase-stable alloys.  Long-term properties degrade in industrial systems which operate using high-temperature and chemically-aggressive conditions.
• Thermoelectric materials with high conversion efficiency.  Thermoelectric materials convert waste heat into electricity, and can help recapture lost energy.
• Lightweight, high-strength ductile materials.  Trade-offs typically exist: strength at the expense of ductility; light weight at the expense of strength; and so on.
• Irradiation-resistant structural alloys for nuclear applications.  Nuclear irradiation degrades the mechanical properties of many materials. 
• High-pressure hydrogen-resistant materials.  Storage and handling of hydrogen is not an easy task.
• Collaborative, comprehensive materials database.  Materials development can be sped and cost reduced.
• Predictive materials performance code.  Computer modeling of materials' mechanical properties will enable rapid, inexpensive, and iterative development.

Multi-Materials Integration in Energy Systems (or: composites to provide what the individual components can't).  This includes:

• Low-cost carbon fibers and composites manufacturing processes.  Carbon fiber products are too expensive to manufacture for widespread use.
• Joining process for assembling multi-material structures. Some material pairs are incompatible (i.e. structurally or chemically) and can not form suitable joints or be brought into contact.
• High energy density, low-cost battery cathodes.  Improved battery longevity, storage, and discharge will enable new alternative energy technologies.
• Low-cost fuel cell catalyst.  A current benchmark catalyst, Platinum, rare and expensive, is not ideal.
• Integrated computational materials engineering modeling package.  Initial composite design and proof-of-concept can be performed first through computation, saving development time and costs.

Sustainable Manufacturing of Materials.  This includes:

• Net-shape processing of structural metals.  Scrap and waste (e.g. from machining a block of steel into its final shape) can be reduced.
• Additive manufacturing of components and systems.  Energy-intensive production methods and industrial systems as a whole can be made more efficient.
• Low-cost processing and energy reduction technology for metals.  Lightweight metals such as aluminum, titanium, and magnesium can benefit greatly from improved processing methods.
• Separation of materials for recycling.  Major efficiency barriers surround the screening and sorting of mixed materials.  Carbon fiber recycling is also expensive.
• Real-time sensor technology for gases and molten metals.  Enhanced detection methods are needed for identifying damage during processing of high-performance and energy-intensive products. 

This report covers a lot of ground regarding sustainability of materials science and engineering in energy and related fields.  But it also presents a good overview of the diversity and breadth of the meaning or interpretation of sustainability - an important point that should be considered alongside the sustainability design itself.  

[1] Linking Transformational Materials and Processing for an Energy-Efficient and Low-Carbon Economy: Creating the Vision and Accelerating Realization - Opportunity Analysis for Materials Science and Engineering.  The Mining, Metals, and Materials Society (2011).  (Available On-Line.)
[2] L. Robinson.  Opportunity analysis for MSE - Report defines pathway to a more sustainable energy future.  JOM, Vol. 63 (Issue 2) (2011), pp. 30-33.