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The currently reported bottom water sealing materials and fracturing technologies can hardly simultaneously achieve the high production and low water cut of gas reservoirs due to the complexity of various formation conditions. Therefore, without controlling the fracturing scale and injection volume, a kind of polylactide polymer water plugging material with a density of 1.15–2.0 g/cm3 is developed, which can be used to seal the bottom water of a gas–water differential layer by contact solidification with water and automatic degradation with natural gas. This technology can not only fully release the production capacity of the gas reservoir but also effectively control water production and realize the efficient fracturing development of the target gas reservoir. Laboratory test results show that the smart plugging agent has a bottom water plugging rate of 100%, and the low-density plugging agent has a dissolution rate of 96.7% in methane gas at 90 °C for 4 h and a dissolution rate of 97.6% in methane gas at 60 °C for 6 h, showing remarkable gas degradation performance. In addition, settlement experiments show that the presence of a proppant can increase the settlement rate of a plugging agent up to many times (up to 21 times) in both water and guanidine gum solution. According to the actual conditions of well J66-8-3, a single-well water plugging fracturing scheme was prepared by optimizing the length of fracture, plugging agent dosage, and plugging agent sinking time, and a post-evaluation method was proposed. It has guiding significance to the development of similar gas reservoirs. [ABSTRACT FROM AUTHOR]

The excellent electrical conductivity of graphene is due to its highly‐conjugated structures. Manipulation of the electronic and mechanical properties of graphene can be achieved by controlling the destruction of its in‐sheet conjugation system. Herein, we report the preparation of CoCeSx−SA@BPMW@RGO through π‐π stacking interactions at the molecular level. In this study, sodium alginate was reacted with Co2+ and Ce3+, and the composite was loaded onto a graphene surface. The graphene sheets were prepared using a bi‐pyrene terminated molecular wire (BPMW) to avoid re‐stacking of the grapheme sheets, thereby forming nanoscale spaces between sheets. The angle between the BPMW coplanar pyrene group and the phenyl group was 33.2°, and the graphene layer is supported in an oblique direction. Finally, a three‐dimensional porous composite was obtained after annealing and vulcanization. The obtained CoCeSx−SA@BPMW@RGO exhibited excellent electrical conductivity and remarkable cycle stability. When the current density was 1 A g−1, its specific capacitance was as high as 1004 F g−1. BPMW modifies graphene through the synergistic effect of π‐π stacking interaction and special structure to obtain excellent electrochemical performance. Moreover, a solid‐state asymmetric supercapacitor device was fabricated based on the synthesized CoCeSx−SA@BPMW@RGO hybrid, which exhibited a power density of 979 W kg−1 at an energy density of 23.96 Wh kg−1. [ABSTRACT FROM AUTHOR]