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Abstract Hierarchically porous materials containing sub-nm ultramicropores with molecular sieving abilities and microcavities with high gas diffusivity may realize energy-efficient membranes for gas separations. However, rationally designing and constructing such pores into large-area membranes enabling efficient H2 separations remains challenging. Here, we report the synthesis and utilization of hybrid carbon molecular sieve membranes with well-controlled nano- and micro-pores and single zinc atoms and clusters well-dispersed inside the nanopores via the carbonization of supramolecular mixed matrix materials containing amorphous and crystalline zeolitic imidazolate frameworks. Carbonization temperature is used to fine-tune pore sizes, achieving ultrahigh selectivity for H2/CO2 (130), H2/CH4 (2900), H2/N2 (880), and H2/C2H6 (7900) with stability against water vapor and physical aging during a continuous 120-h test.

Based on the theoretical basis of Myers (1977) and Ohlson (1995), this study explored the effect of R&D expenses as a company's exploratory activities and advertising expenses as an activity that utilizes existing capabilities on corporate value. As a way for companies to explore new capabilities, the effect of R&D expenses on corporate value is examined, and as a method for strengthening existing capabilities and strengthening market competitiveness, the effect of advertising expenses on corporate value is considered. The empirical analysis subjects of this study are companies listed on the Korean stock market from 2011 to 2021. Ultimately, the number of sample data used in the empirical analysis of this study is 9,220 firm-year, and all are extracted from the KIS-VALUE DATABASE. In an empirical analysis using a regression model, the relationship between R&D and advertising R&D expenses on corporate value is investigated. The results of the regression analysis showed that both R&D expenses and advertising expenses had a positive effect on corporate value. An increase in R&D expenses increases corporate value by increasing future growth opportunities beyond a company's present value, and an increase in advertising expenses maximizes product or service value and enhances corporate value by strengthening market competitiveness. In addition, it is found that the impact of R&D expenses on corporate value is greater than that of advertising expenses, indicating the importance of R&D as a company's exploratory activities. These results provide important implications for corporate strategic management. Companies can achieve corporate value improvement through strategic investment and management of R&D and advertising expenses. Companies can strengthen their competitiveness through R&D as a future exploration activity and through advertising to create results in the existing market. [ABSTRACT FROM AUTHOR]