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For the direct pressure measurement method, the strict requirements for the selection of test locations and the quality of the sealing lead to a lower success rate of pressure measurement, high test cost and long cycle; while the indirect pressure measurement method has certain deficiencies in experimental operation, technical requirements, etc., a gas pressure measurement technology based on the principle of “state restoration” is proposed for non-sealing coal seams. Relying on the self-developed non-sealing coal seam gas pressure tester, six adsorption equilibrium pressures of 0.10 MPa, 0.31 MPa, 0.53 MPa, 0.74 MPa, 1.00 MPa and 1.50 MPa were set to simulate the occurrence conditions of coal. Through pressure unloading and atmospheric desorption to simulate the downhole sampling process, then carry out quantitative gas supplementation at atmospheric pressure, coal core volume restoration and temperature simulation of reservoir condition, so that the pressure test sample can be stabilized under the same conditions as the reservoir environment. Finally, the six pressure recovery values are 0.09 MPa, 0.30 MPa, 0.50 MPa, 0.73 MPa, 1.01 MPa and 1.61 MPa respectively; the errors of the corresponding initial adsorption equilibrium pressure are -10.00%, -3.23%, -5.66%, -1.35%, 1.00%, 7.33%. The overall error range is between -10.00% and 7.33%, which verifies the feasibility of the gas pressure measurement technology for the non-sealing coal seam.

The diversity in molecular structures and solution processability of non‐fullerene acceptors (NFAs), particularly those containing selenium (Se), plays a pivotal role in advancing organic solar cells (OSCs). Among various molecular design strategies, the introduction of selenium atoms, characterized by their large covalent radius, loose electron cloud, and strong polarization properties, can enhance intermolecular Se‐Se interactions and improve the electron‐donating capability of π‐cores. This approach is considered a significant avenue for optimizing the photovoltaic performance of active layer materials. In this review, we provide a comprehensive summary of recent advancements in selenium‐containing acceptor molecules. These include ITIC‐based fused ring NFAs, Y6‐based fused ring NFAs, Y6‐based polymer acceptors, non‐fused ring electron acceptors and their application in tandem and ternary OSCs. Additionally, we analyze the future prospects and development of selenium‐containing NFAs with the goal of achieving OSC efficiencies exceeding 20 %. [ABSTRACT FROM AUTHOR]

Achieving a more balanced charge transport by morphological control is crucial in reducing bimolecular and trap‐assisted recombination and enhancing the critical parameters for efficient organic solar cells (OSCs). Hence, a facile strategy is proposed to reduce the crystallinity difference between donor and acceptor by incorporating a novel multifunctional liquid crystal small molecule (LCSM) BDTPF4‐C6 into the binary blend. BDTPF4‐C6 is the first LCSM based on a tetrafluorobenzene unit and features a low liquid crystal phase transition temperature and strong self‐assembly ability, conducive to regulating the active layer morphology. When BDTPF4‐C6 is introduced as a guest molecule into the PM6 : Y6 binary, it exhibits better compatibility with the donor PM6 and primarily resides within the PM6 phase because of the similarity‐intermiscibility principle. Moreover, systematic studies revealed that BDTPF4‐C6 could be used as a seeding agent for PM6 to enhance its crystallinity, thereby forming a more balanced and favourable charge transport with suppressed charge recombination. Intriguingly, dual Förster resonance energy transfer was observed between the guest molecule and the host donor and acceptor, resulting in an improved current density. This study demonstrates a facile approach to balance the charge mobilities and offers new insights into boosting the efficiency of single‐junction OSCs beyond 20 %. [ABSTRACT FROM AUTHOR]