With the increasingly severe climate change situation and the trend of green energy transformation, the development and utilization of hydrogen energy has attracted extensive attention from government, industry, and academia in the past few decades. Renewable energy electrolysis stands out as one of the most promising hydrogen production routes, enabling the storage of intermittent renewable energy power generation and supplying green fuel to various sectors. This article reviews the evolution and development of green hydrogen policies in the United States, the European Union, Japan, and China, and then summarizes the key technological progress of renewable energy electrolysis while introducing the progress of hydrogen production from wind and photovoltaic power generation. Furthermore, the environmental, social, and economic benefits of different hydrogen production routes are analyzed and compared. Finally, it provides a prospective analysis of the potential impact of renewable energy electrolysis on the global energy landscape and outlines key areas for future research and development.

The dynamic adsorption characteristics of K₂CO₃-promoted layered double hydroxides (LDHs)-based adsorbent, with organic and inorganic anion intercalation, were studied. MgAl–LDH, K₂CO₃/MgAl–LDH, and K₂CO₃/MgAl–LDH(C16) with varying K₂CO₃ loads were prepared and used for intermediate-temperature CO₂ sequestration. The adsorbent was thoroughly characterized using X-ray diffraction, Brunauer–Emmett–Teller, scanning electron microscopy, and Fourier Transform Infrared Spectroscopy techniques, which revealed enhanced adsorption properties of MgAl–LDH, due to K₂CO₃ promotion. Thermogravimetric CO₂ adsorption tests on the constructed adsorbent materials showed that the 12.5 wt% K₂CO₃/MgAl–LDH(C16) adsorbent with organic anion intercalation exhibited optimal adsorption activity, achieving an adsorption capacity of 1.12 mmol/g at 100% CO₂ and 350 °C. However, fixed-bed dynamic adsorption tests yielded different results; the 25 wt% K₂CO₃/MgAl–LDH prepared through inorganic anion intercalation exhibited the best adsorption performance in low-concentration CO₂ penetration tests. The recorded penetration time was 93.1 s, accompanied by an adsorption capacity of 0.722 mmol/g. This can be attributed to the faster adsorption kinetics exhibited by the 25 wt% K₂CO₃/MgAl–LDH adsorbent during the early stages of adsorption, thereby facilitating efficient CO₂ capture in low-concentration CO₂ streams. This is a conclusion that differs from previous reports. Earlier reports indicated that LDHs with organic anion intercalation exhibited higher CO₂ adsorption activity in thermogravimetric analyzer tests. However, this study found that for the fixed-bed dynamic adsorption process, K₂CO₃-modified inorganic anion-intercalated LDHs perform better, indicating their greater potential in practical applications.

Amine-based CO₂ capture represents the most mature approach for large-scale carbon reduction, with systems implemented across multiple industrial demonstration projects globally. However, vast chemical spaces encompassing millions of potential formulations and complex multiscale coupling effects pose unprecedented challenges for traditional experimental methods. Machine learning applications have achieved revolutionary advances through differentiated strategies. In liquid amine systems, ensemble learning algorithms delivered breakthrough precision improvements from traditional 4–5% to below 0.93%, while interpretable models revealed that nitrogen atom charge distribution contributes 56% to reaction barriers, enabling rational biphasic solvent design (DETA/DEEA system) that achieved 34% regeneration energy reduction compared to benchmark MEA. For solid amine systems, differential descriptor methods overcame severe overfitting challenges, improving test set performance from R² = 0.5102 to 0.79. Virtual screening of 1.6 million binding sites from the GDB-17 database identified 11% of candidates with stronger CO₂ binding than the industrial benchmark BPEI (−0.04 eV). Among these high-performance candidates, 2642 molecules simultaneously satisfied synthesizability criteria (SAscore < 3.4, GDBscore > 0.64), demonstrating both favorable binding energetics and high experimental feasibility. Critically, mechanistic analysis revealed that support physical properties dominate adsorption performance over amine chemical characteristics, fundamentally transforming material design concepts. Industrial applications demonstrated 35.76% cost reductions through intelligent solvent selection and 15–25% profit improvements through dynamic capture-level optimization combined with market-responsive bidding strategies. Despite these breakthroughs, systematic limitations, including model generalization difficulties, cross-scale integration challenges, and data standardization, persist, requiring physics-constrained algorithms and unified modeling frameworks for laboratory-to-industrial translation. These developments establish machine learning as the core driving force transitioning amine-based CO₂ capture from empirical development toward intelligent design paradigms.

The urgent need to mitigate rising global CO₂ emissions demands the development of efficient carbon capture technologies. This study addresses the persistent challenge of sintering-induced performance degradation in CaO-based sorbents during high-temperature CO₂ capture. A novel solvent/nonsolvent synthetic strategy to fabricate CaO/CaAl-layered double oxide (LDO) composites was developed, where CaAl-LDO serves as a nanostructural stabilizer. The CaAl-LDO precursor enables atomic-level dispersion of components, which upon calcination forms a Ca₁₂Al₁₄O₃₃ “rigid scaffold” that spatially confines CaO nanoparticles and effectively mitigates sintering. Thermogravimetric analysis results demonstrate exceptional cyclic stability; the composite achieves an initial CO₂ uptake of 14.5 mmol/g (81.5% of theoretical capacity) and retains 87% of its capacity after 30 cycles. This performance significantly outperforms pure CaO and CaO/MgAl-LDO composites. Physicochemical characterization confirms that structural confinement preserves mesoporous channels, ensuring efficient CO₂ diffusion. This work establishes a scalable, instrumentally simple route to high-performance sorbents, offering an efficient solution for carbon capture in energy-intensive industries such as power generation and steel manufacturing.

Converting CO₂ to methane via catalytic routes is an effective way to control the CO₂ content released in the atmosphere while producing value-added fuels and chemicals. In this study, the CO₂ methanation performance of highly dispersed Ni-based catalysts derived from aqueous miscible organic layered double hydroxides (AMO-LDHs) was investigated. The activity of the catalyst was found to be largely influenced by the chemical composition of Ni metal precursor and loading. A Ni-based catalyst derived from AMO-Ni₃Al₁-CO₃ LDH exhibited a maximum CO₂ conversion of 87.9% and 100% CH₄ selectivity ascribed to both the lamellar catalyst structure and the high Ni metal dispersion achieved. Moreover, due to the strong Ni metal–support interactions and abundant oxygen vacancy concentration developed, this catalyst also showed excellent resistance to carbon deposition and metal sintering. In particular, high stability was observed after 19 h in CO₂/H₂ reaction at 360 °C.

Carbon capture, utilization and storage (CCUS) is indispensable for achieving global carbon neutrality, and amine-based chemical absorption remains the most mature and widely deployed technology. However, amine emissions during operation result in absorbent loss, secondary pollution and potential public health risks, while conventional offline detection methods are unable to satisfy the requirements of real-time monitoring. This review systematically summarizes recent progress in metal oxide semiconductor (MOS) gas sensors for monoethanolamine (MEA) detection, with particular emphasis on AOx-based systems. The effects of the base material, microstructure and modification strategies, including noble metal decoration and heterojunction construction, on sensing performance are critically compared. Through such modifications, AOx-based sensors have achieved markedly improved sensing performance, and several are capable of detecting MEA at room temperature. The feasibility of existing sensing materials is further evaluated in the context of post-combustion amine capture. Among the reported systems, SnO₂-based sensors exhibit clear advantages for MEA detection, including high sensitivity, favorable selectivity, rapid response and recovery, and satisfactory stability and repeatability. In contrast, studies on ABO₃ perovskite-based sensors remain limited; although these materials show fast response, they continue to suffer from poor stability and insufficient humidity resistance. Future research should therefore focus on low-temperature operation, enhanced humidity tolerance and long-term durability, so as to accelerate the industrial translation of MOS gas sensors and support the sustainable development of CCUS.