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Abstract Lakes, ponds, and reservoirs (hereafter: “lakes”) are important sources of the greenhouse gases carbon dioxide (CO₂) and methane (CH₄). Emissions of CO₂and CH₄from lakes are regulated in part by in-lake processes, including the production and storage of gases in the lower parts of the water column (bottom waters). However, while substantial efforts have been made to improve estimates of greenhouse gas emissions from lakes, limited data on gas concentrations along depth profiles have prevented the incorporation of bottom-water processes in global emission estimates. Here, we present GHG-depths: the largest existing dataset of depth-profile CO₂and CH₄measurements worldwide, including 522 lakes across 38 countries and all seven continents. These data include contributions from 45 research teams and 56 published studies, totaling 2558 discrete sampling events. As global change continues to alter biogeochemical cycling in lakes, these data can help improve mechanistic models to better predict greenhouse gas production and emission from lakes worldwide. 

Metal–Organic Frameworks (MOFs) have emerged as advanced porous crystalline materials due to their highly ordered structures, ultra-high surface areas, fine-tunable pore sizes, and massive chemical diversity. These features, arising from the coordination between an almost unlimited number of metal ions/clusters and organic linkers, have resulted in significant interest in MOFs for applications in gas storage, catalysis, sensing, energy, and biomedicine. Beyond their stand-alone properties and applications, recent research has increasingly explored the integration of MOFs with other substrates, particularly electrodes, polymeric thin films, and glass surfaces, to create synergistic effects that enhance material performance and broaden application potential. Coating MOFs onto these substrates can yield significant benefits, including, but not limited to, improved sensitivity and selectivity in electrochemical sensors, enhanced mechanical and separation properties in membranes, and multifunctional coatings for optical and environmental applications. This review provides a comprehensive and up-to-date summary of recent advances (primarily from the past 3–5 years) in MOF coating techniques, including layer-by-layer assembly, in situ growth, and electrochemical deposition. This is followed by a discussion of the representative applications arising from MOF-substrate coating and an outline of key challenges and future directions in this rapidly evolving field. This article aims to serve as a focused reference point for researchers interested in both fundamental strategies and applied developments in MOF surface coatings. 

Enzymes are advanced biocatalysts, while immobilizing enzymes on solid supports, particularly metal–organic frameworks (MOFs), enhances enzyme stability, reusability, and substrate selectivity. One-pot cocrystallization (CC) of enzymes in MOFs in the aqueous phase avoids enzyme size limitation and leaching; our recent CC MOF “library” offers a collection of metal–ligand combinations for customizable enzyme immobilization [ACS Appl. Mater. Interfaces 2022, 14, 46, 51619–51629]. However, CC generally suffers from low yield and stability. Mechanochemical or liquid-assisted grinding (LAG) synthesis overcomes this issue, yet most current approaches use metals, ligands, and enzymes in powder states with organic solvents, limiting eco-friendliness and enzyme compatibility. Water as an eco-friendly LAG synthesis agent (eco-LAGent) offers a greener medium to preserve protein folding states, hydration shells, and conformational flexibility, essential for activity. However, only one MOF has been reported to be synthesized this way. Due to the different metal–ligand contact mechanisms, MOFs by CC or eco-LAGent synthesis may not have the same crystal structures either, yet there is a lack of data to compare. Here, we expand the “library” of enzyme@MOF biocatalysts synthesized in an eco-LAGent, water, using abundant, low-toxicity metal ions and ligands, achieving improved thermal and pH stability and significantly enhanced enzyme@MOF yields while proving the high chance of scaling up and eventually industrial applications. Grinding also impacted the interface of metal–ligand contact─compared to aqueous-phase CC, eco-LAGent synthesis increased the crystallinity in 3 MOFs, generated new MOF structures in another 3, and improved the thermal and pH stability across most resultant enzyme@MOF cocrystals. This study generalizes the eco-LAGent synthesis to more MOFs and opens a new avenue to encapsulate enzymes in high-quality crystals with a customized selection of metal ions and ligands (according to enzymes and applications) under green and scalable conditions. 

Abstract High-latitude and altitude cold regions are affected by climate warming and permafrost degradation. One of the major concerns associated with degrading permafrost is thaw subsidence (TS) due to melting of excess ground ice and associated thaw consolidation. Field observations, remote sensing, and numerical modeling are used to measure and estimate the extent and rates of TS across broad spatial and temporal scales. Our new data synthesis effort from diverse permafrost regions of North America and Eurasia, confirms widespread TS across the panarctic permafrost domain with rates of up to 2 cm yr⁻¹in the areas with low ice content and more than 3 cm yr⁻¹in regions with ice-rich permafrost. Areas with human activities or areas affected by wildfires exhibited higher subsidence rates. Our findings suggest that permafrost landscapes are undergoing geomorphic change that is impacting hydrology, ecosystems, and human infrastructure. The development of a systematic TS monitoring is urgently needed to deliver consistent and continuous exchange of data across different permafrost regions. Integration of coordinated field observations, remote sensing, and modeling of TS across a range of scales would contribute to better understanding of rapidly changing permafrost environments and resulting climate feedbacks.