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The geological circle has been studying the South China Ocean for 40 years. Based on the existing studies, the geological features of the middle Neogene South China Ocean and related geological structures and mineralization issues have been further understood through the topics of Regional Geology of China: Jiangxi, Mineral Geology of China: Jiangxi, and Evolution and Mineralization in South China Ocean–Marginal Pacific. The Pingxiang–Shexian–Suzhou junction zone connects the Jinsha River–Red River junction zone to the north of Henei, which is the subduction zone of the South China Ocean in the middle Neogene. It formed the boundary between the Yangtse plate and the newly-defined China-Southeast Asia plate (referred to as the Jinsha River–Red River–Shexian–Suzhou junction zone), which is now a latitudinal tectonic belt bending southward. The South China Ocean is a Meso-Neoproterozoic ocean between the Yangzi Paleo-plate and the Cathaysia-Southeast Asia Paleo-plate, closed at about 820± Ma. The Jinning movement took place during the collision of the plates, resulting in a consolidation of the Yangtze Block and the Cathaysia-Southeast Asia Block, where they united into one. The region has been an essential part of the Eurasian plate since the Indo-Chinese period, and the South China Rift System had been formed from 815± Ma in the late Neogene to the early Paleozoic. The Tethys and Paleo-Pacific tectonic domains have formed the geological tectonic framework of southern China and plateaus, continents, seas, and island arcs of the neighboring areas since the late Paleozoic. The subduction zone of the South China Ocean has evolved into the “Jinsha River–Hong River–Qinzhou Bay–-Hangzhou Bay” mega metallogenic belt of tungsten-tin-copper-gold polymetallic precious and rare metals, featuring two major magmatic mineralization series of S and I types.

Direct‐ammonia proton ceramic fuel cell (DA‐PCFC) is a promising clean energy technology because ammonia (NH3) is easier to store, transport, and handle than hydrogen. However, NH3 decomposition efficiency is unsatisfactory, and the anti‐sintering resistance of conventional Ni‐based ceramic anodes has limited the large‐scale application of DA‐PCFC technology. Herein, Pr0.6Sr0.4(Co0.2Fe0.8)0.85Ru0.15O3‐δ (PSCFR15), a novel anode catalyst layer (ACL) material is developed. PSCFR15 is treated under a reducing atmosphere to form a composite with CoFeRu alloy nanoparticles. Density functional theory simulations reveal that Ru modification in the CoFe alloy promotes nitrogen desorption during ammonia decomposition reaction, thereby boosting ammonia decomposition efficiency. As a result, DA‐PCFC with PSCFR15 ACL can achieve superior peak power density compared to bare DA‐PCFC operated with H2 and NH3 fuels. Furthermore, the ACL also reduces the direct contact between the Ni‐based ceramic anode and the NH3 fuel, then suppressing Ni sintering, and enhancing the durability of the DA‐PCFC. [ABSTRACT FROM AUTHOR]

Solid oxide cells (SOCs) hold considerable promise as devices for efficient, reversible conversion between chemical and electrical energy, facilitating a global shift toward renewable energy. Electrode performance is critical for SOC efficiency and durability and composite materials are key to developing high‐performance electrode catalysts. However, conventional mechanical mixing and infiltration methods often lead to large particle sizes, uneven distribution, and weak interfacial interactions, thus limiting electrochemical activity and longevity. Recent advancements have produced powerful new strategies for creating composite materials. These include metal exsolution and oxide segregation for fuel electrodes and one‐pot synthesis, segregation, phase reaction, and dynamic cation exchange for air electrodes. These techniques yield highly active, uniform nano‐catalysts and robust multi–phase interfacial contacts, significantly improving electrochemical activity and durability. This work reviews these advanced strategies and their applications in SOCs. It provides valuable insights for designing and optimizing SOC catalyst materials, accelerating the development of this vital energy conversion technology. [ABSTRACT FROM AUTHOR]

Author(s): Yuan Zhang [sup.1] , Bin Chen [sup.2] [sup.3] , Daqin Guan [sup.1] , Meigui Xu [sup.1] , Ran Ran [sup.1] , Meng Ni [sup.2] , Wei Zhou [sup.1] , [...], One challenge for the commercial development of solid oxide fuel cells as efficient energy-conversion devices is thermo-mechanical instability. Large internal-strain gradients caused by the mismatch in thermal expansion behaviour between different fuel cell components are the main cause of this instability, which can lead to cell degradation, delamination or fracture.sup.1-4. Here we demonstrate an approach to realizing full thermo-mechanical compatibility between the cathode and other cell components by introducing a thermal-expansion offset. We use reactive sintering to combine a cobalt-based perovskite with high electrochemical activity and large thermal-expansion coefficient with a negative-thermal-expansion material, thus forming a composite electrode with a thermal-expansion behaviour that is well matched to that of the electrolyte. A new interphase is formed because of the limited reaction between the two materials in the composite during the calcination process, which also creates A-site deficiencies in the perovskite. As a result, the composite shows both high activity and excellent stability. The introduction of reactive negative-thermal-expansion components may provide a general strategy for the development of fully compatible and highly active electrodes for solid oxide fuel cells. Highly active but durable perovskite-based solid oxide fuel cell cathodes are realized using a thermal-expansion offset, achieving full thermo-mechanical compatibility between the cathode and other cell components.

Due to the high energy density, mature production technology, ease of storage and transportation, and the no carbon/sulfur nature of ammonia fuel, direct-ammonia solid oxide fuel cells (DA-SOFCs) have received rapidly increasing attention, showing distinct advantages over H2-fueled SOFCs and low-temperature fuel cells. However, DA-SOFCs with conventional Ni-based cermet anodes still suffer from several drawbacks, including serious sintering and inferior activity for ammonia decomposition, strongly limiting the large-scale applications. To tackle the above-mentioned issues, exsolved NiCo nanoparticles decorated double perovskite oxides are fabricated and employed as high-performance anodes for DA-SOFCs in this work. By optimizing the Ni doping amount in Sr2CoMo1−xNixO6−δ (x = 0.1, 0.2 and 0.3), the reduced Sr2CoMo0.8Ni0.2O6−δ (r-SCMN2) anode exhibits superb catalytic activity for ammonia cracking reaction and high anti-sintering capability. More specifically, the electrolyte-supported single cell with r-SCMN2 nanocomposite anode delivers superior power outputs and operational durability in ammonia fuel as compared with other r-SCMN anodes owing to the significantly promoted nanoparticle exsolution and stronger interaction between alloy nanoparticles and the support. In summary, this study presents an effective strategy for the design of efficient and stable nanocomposite anodes for DA-SOFCs. [ABSTRACT FROM AUTHOR]

Compared with conventional oxygen-ion-conducting solid oxide fuel cells (O–SOFCs), proton ceramic fuel cells (PCFCs) are more attractive for low-temperature operation due to their smaller activation energy and higher ionic conductivity at reduced temperatures. However, most of the PCFCs still exhibit lower power outputs than O–SOFCs until now due to the lack of suitable and high-performance cathode materials. Cobalt (Co)-based perovskite oxides have been widely employed as cathodes for PCFCs, and suffer from poor thermo-mechanical compatibility with the electrolyte and inferior structural stability. Herein, Co-free triple-conducting perovskite-based nanocomposites are reported as highly active and stable cathodes for PCFCs. By tailoring the Ce/Y co-doping amounts in BaFeO3−δ, Ba(Ce0.8Y0.2)xFe1−xO3−δ (x = 0.1, 0.2 and 0.3) perovskites experience a phase transformation from a single-phase (x = 0.1, O2−/e− conducting) into a composite (x = 0.2 and 0.3, O2−/e− and H+/e− conducting) to achieve triple-conducting capability. The optimized BaCe0.16Y0.04Fe0.8O3−δ nanocomposite cathode displays superior activity for the oxygen reduction reaction (ORR) with low area-specific resistances of 0.27 and 1.49 Ω cm2 at 600 and 500 °C, respectively, surpassing most of the reported Co-free PCFC cathodes. The BaCe0.16Y0.04Fe0.8O3−δ cathode also exhibits superior thermo-mechanical compatibility with BaZr0.1Ce0.7Y0.1Yb0.1O3−δ electrolyte and improved CO2 tolerance due to the strong interaction between O2−/e− and H+/e− conducting phases and the optimized dual-phase composition. Consequently, an anode-supported single cell with the BaCe0.16Y0.04Fe0.8O3−δ cathode delivers a high peak power density of 829 mW cm−2 at 650 °C and a durable operation for ∼450 h at 550 °C. This work provides a highly promising Co-free cathode for PCFCs, which may accelerate the commercialization of this technology. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) water splitting is an attractive strategy for the large‐scale production of renewable hydrogen from water. Developing cost‐effective, active and stable semiconducting photoelectrodes is extremely important for achieving PEC water splitting with high solar‐to‐hydrogen efficiency. Perovskite oxides as a large family of semiconducting metal oxides are extensively investigated as electrodes in PEC water splitting owing to their abundance, high (photo)electrochemical stability, compositional and structural flexibility allowing the achievement of high electrocatalytic activity, superior sunlight absorption capability and precise control and tuning of band gaps and band edges. In this review, the research progress in the design, development, and application of perovskite oxides in PEC water splitting is summarized, with a special emphasis placed on understanding the relationship between the composition/structure and (photo)electrochemical activity. [ABSTRACT FROM AUTHOR]

Photoelektrochemische (PEC‐)Wasserspaltung bietet eine vielversprechende Möglichkeit zur Massenproduktion von erneuerbarem Wasserstoff aus Wasser. Zum Erzielen einer PEC‐Wasserspaltung mit hoher Effizienz für die Umwandlung von Solarenergie in Wasserstoff ist die Entwicklung kostengünstiger, aktiver und beständiger Halbleiter‐Photoelektroden von großer Bedeutung. Perowskitoxide als eine große Familie von Halbleiter‐Metalloxiden sind als Elektroden für die PEC‐Wasserspaltung intensiv untersucht worden; die Gründe hierfür sind ihre Häufigkeit, ihre hohe (photo)elektrochemische Stabilität, ihre Flexibilität bezüglich Zusammensetzung und Struktur, die eine Optimierung der elektrokatalytischen Aktivität ermöglicht, das überlegene Sonnenlichtabsorptionsvermögen sowie die präzise Steuer‐ und Abstimmbarkeit von Bandlücken und ‐kanten. In diesem Aufsatz werden die Fortschritte bei der Gestaltung, Entwicklung und Anwendung von Perowskitoxiden für die PEC‐Wasserspaltung zusammengefasst, mit besonderem Schwerpunkt auf dem Verständnis der Beziehung zwischen Zusammensetzung/Struktur und (photo)elektrochemischer Aktivität. [ABSTRACT FROM AUTHOR]