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Polymer‐derived ceramic (PDC) processing represents a versatile complement for the preparation of ceramic coatings. Filler‐loaded preceramic polymer layers can be deposited by methods such as dip coating even on substrates with a complex geometry, and subsequent thermal processing results in the formation of ceramic coatings. This specific polymer‐to‐ceramic processing route allows to tailor the coating's characteristics, e.g., surface‐structured coatings, thermal barrier coatings, and coatings for tribological applications. As coating systems polysilazanes and polysilsesquioxanes were combined in different approaches with PDC spheres, hexagonal, and cubic boron nitride.

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CO 2 emissions should be cut in half by 2050 compared to 2009 in order to limit the increase in the world average temperature to 2 °C. Despite the advances in renewable energy alternatives, their supply strongly depends on favorable weather conditions and their efficient storage is still difficult. Thus, the key factor for the transition towards a more sustainable future relies on decarbonizing power generation. Alone the substitution of heavy fossil fuels by natural gas can decrease the related emissions in ≈50%. [1][2][3][4] Nevertheless, a developing interest has been shown for carbon-free sources as ammonia and liquid hydrogen, which are potential fuel alternatives to produce energy with a cleaner emission profile. [5] Besides the compactness and low maintenance costs, gas turbines can operate with versatile fuel sources, which make them a natural choice for the efficient production of energy. For this reason, they have found increasing service in the past 40 years in the power industry both among utilities and industrial plants as well as for aviation. [6] In combined cycle operation and with inlet temperatures exceeding 1400 °C, efficiencies as high as 63% can be achieved. [2] Therefore, different strategies are adopted to protect the currently used Nibased superalloys such as the deposition of yttria-stabilized-zirconia thermal barrier coatings (TBC) and intensive film cooling. This standard is, however, not realistic when considering service for considerable amount of times (t > 10 000 h), since the rapid creep of the TBC at above 900 °C, associated with the great mismatch between its coefficient of thermal expansion (CTE) with the alloy, increase the risk of spallation and limit the use of metal-based components in turbine engines. [7][8][9][10] Especially envisioning the use of carbon-free fuel sources in future gas turbines like hydrogen or ammonia, water vapor is one of the main products of combustion, which intensifies the degradation of these alloys. [5,[11][12][13] Hence, advances towards reduced greenhouse gas emissions and more efficient gas turbines require their substitution by more robust materials resistant to oxidation and corrosion, which can endure service at higher temperatures.Due to their reduced density, lower CTE (3-5.5 × 10 −6 K −1 ), high temperature creep resistance and melting points, nonoxide silicon based ceramics as Si 3 N 4 , SiC, and SiC/SiC composites stand out for application in combustion environments. [14][15][16][17][18][19][20][21] In face of an accelerating climate change, the reduction and substitution of fossil fuels is crucial to decarbonize energy production. Gas turbines can operate with versatile fuel sources like natural gas and future fuels such as hydrogen and ammonia. Furthermore, thermal efficiencies above 60% can be achieved using non-oxide silicon-based ceramic components. However, water vapor is one of the main combustion products leading to rapid corrosion because of volatilization of the protective SiO 2 layer at 1200 °C. An in situ generated Yb 2 Si 2 ...