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As one of the important minerals in marine shale reservoirs, the development characteristics of pyrite can provide guidance for the exploration of deep shale gas resources and the study of high-quality reservoir development mechanisms. In this study, samples of the Wufeng and Longmaxi Formation in the southeast Chongqing area were selected, and the development characteristics of framboidal pyrite were revealed through a combination of qualitative and quantitative method. High-quality reservoirs of the upper Wufeng Formation and the bottom of the Longmaxi Formation are developed with smaller sizes, weaker variation and a narrower size distribution of pyrite framboids compared with other units of the strata, suggesting relatively stable euxinic conditions during deposition. The development characteristics of framboidal pyrite and some of the key reservoir evaluation parameters such as organic matter content and brittle mineral content, etc., are controlled by similar factors. Therefore, pyrite morphological evidence can be used as a potential indicator of high-quality shale reservoirs. [ABSTRACT FROM AUTHOR]

The advancement of CO2 electrolysis has reached a stage where practical CO2 electrolysers show promise for high conversion rate, low manufacturing cost, and extended system durability. While gas diffusion electrodes (GDEs) as flexible cathodes play a pivotal role in flow cell electrolysers, a prevalent issue arises with the implemented GDEs. Electrolyte flooding refers to the infiltration of bulk liquid electrolyte into the GDEs' gas diffusion channels. This typically occurs when the hydrophobicity of the GDEs towards the electrolyte diminishes, and then lowers the conversion efficiency and hence forecloses the durability of CO2 electrolysis. Compared to a proven track record of reporting substantial advancements in various novel catalysts, there is a scarcity of publications addressing the fundamental challenge of electrolyte flooding. In this review, the recent advancements in flexible GDEs for CO2 electrolysis are summarized, covering the evolution of different GDE types used in CO2 electrolysis and the current design trends in various flow cell electrolysers. In addressing the critical challenge, valuable insights into the fundamental mechanisms of triggering electrolyte flooding and in situ or ex situ approaches to observe flooding are discussed. A key segment of this review covers a comprehensive summary and evaluation of state-of-the-art methods of mitigating electrolyte flooding in flexible GDEs for CO2 electrolysis, considering three distinct perspectives within flow cell electrolysers: each layer of GDEs, properties of the membrane, and operating conditions. Finally, we discuss the remaining challenges and propose prospective research directions for alleviating the persistent issue of electrolyte flooding. [ABSTRACT FROM AUTHOR]

The study of deep shale gas (>3500 m) has become a new research hotspot in the field of shale gas research in China. In this study, 16 representative deep shale samples were selected from different layers of the Wufeng–Longmaxi Formation in the Z-3 well in the western Chongqing area to conduct low-field nuclear magnetic resonance (NMR) tests, field-emission scanning electron microscopy (FE-SEM) observation, and fractal modeling. By comparing the differences in pore structure and their influencing factors in representative samples from different layers, the particularities of high-quality reservoirs have been revealed. The results show that the Z-3 well shales mainly develop micropores and mesopores, with pore sizes of 1 nm–200 nm. The fractal dimensions of bound fluid pores D1 (1.6895–2.3821) and fractal dimension of movable fluid pores D2 (2.9914–2.9996) were obtained from T2 spectra and linear fitting, and the pores were divided into three sections based on the NMR fractal characteristics. TOC content was one of the major factors affecting the gas content in the study area. The shale samples in the bottom S1l1-1 sub-layer with a higher TOC content have larger porosity and permeability, leading to enhanced homogeneity of the pore structure and favorable conditions for shale gas adsorption. A comparative understanding of the particularities of pore structure and influencing factors in high-quality reservoirs with higher gas content will provide the scientific basis for further exploration and exploitation of the Wufeng–Longmaxi Formation deep shale reservoirs in the western Chongqing area. [ABSTRACT FROM AUTHOR]

New solvents are considered to be one of the effective methods to facilitate the reaction rate and lower the reaction energy barrier. However, the common method to develop a new solvent has come to a dead end. Thus, a single atom in solvent to produce a single atom solution is designed to create the breakthrough. Eight kinds of single atom solutions are prepared as new absorbents. Experiments prove the single atom in the solutions and their charge-producing effects. A density functional theory model is developed to analyze the microscale characteristics. Meanwhile, it has been applied in carbon dioxide capture. The CO2 desorption rate is intensified in the single atom solution system due to the controlled reaction energy barrier. The results show that single atom solutions produce a maximum voltage of 2.12 V and, thus, contribute to near zero energy consumption by effectively harvesting the substantial waste heat below 373 K. [ABSTRACT FROM AUTHOR]