With the serious impact of fossil fuels on the environment and the rapid development of the global economy, the development of clean and usable energy storage devices has become one of the most important themes of sustainable development in the world today. Supercapacitors are a new type of green energy storage device, with high power density, long cycle life, wide temperature range, and both economic and environmental advantages. In many industries, they have enormous application prospects. Electrode materials are an important factor affecting the performance of supercapacitors. MnO -based materials are widely investigated for supercapacitors because of their high theoretical capacitance, good chemical stability, low cost, and environmental friendliness. To achieve high specific capacitance and high rate capability, the current best solution is to use MnO and carbon composite materials. Herein, MnO -carbon composite as supercapacitor electrode materials is reviewed including the synthesis method and research status in recent years. Finally, the challenges and future development directions of an MnO -carbon based supercapacitor are summarized.

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A pilot-scale process has been developed for green and scalable synthesis of (±)-β-(3,4-dihydroxy­phenyl) lactic acid ((±)-DSS) and their two important derivatives, namely, (±)-IDHP [(±)-iso­propyl 2-hydroxy-3-(3,4-di­hydroxy­phenyl)propano­ate] and (±)-DBZ [(±)-bornyl 2-hydroxy-3-(3,4-di­hydroxy­phenyl)propano­ate]. Subsequent hydrogenation has been carried out by employing Raney Ni as catalyst. The improved process results in higher yields of 47.5% for (±)-DBZ and 49.2% for (±)-IDHP compared to the initial process with a yield of 12% for (±)-DBZ and 18% for (±)-IDHP in our original medicinal chemistry route. Furthermore, kilograms of optical DBZ [(−)-S-DBZ and (+)-R-DBZ, >99% ee] and IDHP [(−)-S-IDHP and (+)-R-IDHP, >99% ee] have been produced by chiral high-performance liquid chromatography in good yield (>84%).

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Uncontrolled flow through different permeability zones in oil reservoirs remains a huge challenge during water flooding, which can significantly limit microbial-enhanced oil recovery (MEOR)) efficiency. The aim of the present work was to use polymer-based plugging to assist MEOR through laboratory simulation and field tests. An indigenous strain HB3 was evaluated under field-relevant conditions. A polymeric HPAM/Cr­(III) plugging system was optimized which was also compatible with the microorganism. Laboratory-based simulation demonstrated the selective plugging with HPAM/Cr­(III) resulting in enhanced oil recovery more significantly in the low-permeability core, increasing from 12.8% to 47.5%, compared to that in the high-permeability one, from 47.1% to 63.2%. A subsequent microbial injection enhanced the oil recovery further, also with more effective enhancement in the low-permeability core, increasing from 49.5% to 70.0% while from 67.5% to 78.0% in the high-permeability one. The field tests involving two water injection and nine oil production wells confirmed the improvement of deep profile control by polymer-based plugging, resulting in a more uniform distribution of water absorption. With subsequent microbial injection, oil recovery was significantly enhanced, achieving an ultimate recovery of 57.6% and a cumulative oil increment of 3486 t in nine wells over the 7 month field tests. It was demonstrated that the application of polymer-based plugging significantly improved MEOR efficiency, providing a new route for EOR, especially for heterogeneous reservoirs.