Chemistry with its key targets of providing materials and processes for conversion of matter is at the center stage of the energy challenge. Most energy conversion systems work on (bio)chemical ...energy carriers and require for their use suitable process and material solutions. The enormous scale of their application demands optimization beyond the incremental improvement of empirical discoveries. Knowledge‐based systematic approaches are mandatory to arrive at scalable and sustainable solutions. Chemistry for energy, “ENERCHEM” contributes in many ways already today to the use of fossil energy carriers. Optimization of these processes exemplified by catalysis for fuels and chemicals production or by solid‐state lightning can contribute in the near future substantially to the dual challenge of energy use and climate protection being in fact two sides of the same challenge. The paper focuses on the even greater role that ENERCHEM will have to play in the era of renewable energy systems where the storage of solar energy in chemical carries and batteries is a key requirement. A multidisciplinary and diversified approach is suggested to arrive at a stable and sustainable system of energy conversion processes. The timescales for transformation of the present energy scenario will be decades and the resources will be of global economic dimensions. ENERCHEM will have to provide the reliable basis for such technologies based on deep functional understanding.
Renewable energy supply systems require knowledge‐based systemic chemical processes and optimized materials. This paper focuses on the even greater role that “ENERCHEM” will have to play in the era of renewable energy systems where the storage of solar energy in chemical carries and batteries is a key requirement. Energy is chemistry.
The design of heterogeneous selective oxidation catalysts based upon complex metal oxides is governed at present by a set of empirical rules known as “pillars of oxidation catalysis”. They serve as ...practical guidelines for catalyst development and guide the reasoning about the catalyst role in the process. These rules are, however, not based upon atomistic concepts and thus preclude their immediate application in for example computer-aided search strategies. The present work extends the ideas of the pillar rules and develops the concept of considering a selective oxidation catalyst as enabler for the execution of a reaction network. The enabling function is controlled by mutual interactions between catalyst and reactants. The electronic structure of the catalyst is defined as a bulk semiconductor with a surface state arising form a terminating over layer being different from the structure of the bulk. These components that can be identified by in situ analytical methods form a chemical system with feedback loops, which is responsible for generating selectivity during execution of the reaction network. This concept is based upon physical observables and could allow for a design strategy based upon a kinetic description that combines the processes between reactants with the processes between catalyst and reactants. Such kinetics is not available at present. Few of the constants required are known but many of them are accessible to experimental determination with in situ techniques.
Nitrogen atoms are essential for the function of biological molecules and thus are and important component of fertilizers and medicaments. Bonds to nitrogen also find nonbiological uses in dyes, ...explosives, and resins. The synthesis of all these materials requires ammonia as an activated nitrogen building block. This situation is true for natural processes and the chemical industry. Knowledge of the various techniques for the preparation of ammonia is thus of fundamental importance for chemistry. The Haber–Bosch synthesis was the first heterogeneous catalytic system employed in the chemical industry and is still in use today. Understanding the mechanism and the translation of the knowledge into technical perfection has become a fundamental criterion for scientific development in catalysis research.
A triumph over trial and error: The Haber–Bosch industrial synthesis of ammonia (the picture shows an industrial installation for this process) has reached such a level of refinement that, in the energy balance the only significant loss is the preparation of the highly pure starting materials. Iron, ruthenium, or molybdenum compounds serve as the catalyst. The development of new catalysts is becoming increasingly effective through a deeper understanding of the basic princi ples involved and less dependent on trial and error.
The intermetallic compounds Pd(3)Ga(7), PdGa, and Pd(2)Ga are found to be highly selective semihydrogenation catalysts for acetylene outperforming established systems. The stability of the crystal ...and electronic structure under reaction conditions allows the direct relation of structural and catalytic properties and a knowledge-based development of new intermetallic catalyst systems. In the crystal structure of PdGa palladium is exclusively surrounded by gallium atoms. The alteration of the Pd coordination in PdGa leads to a strong modification of the electronic structure around the Fermi level in comparison to elemental Pd. Electronic modification and isolation of active sites causes the excellent catalytic semihydrogenation properties.
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