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Simultaneously increasing the activity and stability of the single-atom active sites of M–N–C catalysts is critical but remains a great challenge. Here, we report an Fe–N–C catalyst with nitrogen-coordinated iron clusters and closely surrounding Fe–N 4 active sites for oxygen reduction reaction in acidic fuel cells. A strong electronic interaction is built between iron clusters and satellite Fe–N 4 due to unblocked electron transfer pathways and very short interacting distances. The iron clusters optimize the adsorption strength of oxygen reduction intermediates on Fe–N 4 and also shorten the bond amplitude of Fe–N 4 with incoherent vibrations. As a result, both the activity and stability of Fe–N 4 sites are increased by about 60% in terms of turnover frequency and demetalation resistance. This work shows the great potential of strong electronic interactions between multiphase metal species for improvements of single-atom catalysts. It is challenging to break the activity–stability trade-off in Fe–N–C fuel cell catalysts. Here, the authors show that interactions between iron atoms and clusters accelerate reaction kinetics and suppress demetalation to improve fuel cell stability.

Studies in mice reveal that CREB regulated transcription coactivator 2 (CRTC2) acts as a mediator of mTOR signalling in the liver to regulate SREBP1-controlled lipid homeostasis during feeding and diabetes; overexpression of a CRTC2 mutant defective for mTOR regulation improves the lipogenic program and insulin sensitivity in obese mice. Hepatic control of lipid metabolism SREBP1 is an important transcriptional regulator of lipogenesis. Upon insulin stimulation, it is transported from the endoplasmic reticulum to the Golgi where it is processed, then shuttled to the nucleus to induce genes involved in cholesterol and fatty acid synthesis. From studies in mice, Yiguo Wang and colleagues show that the CREB regulated transcription coactivator 2 (CRTC2) acts as a mediator of mTOR signalling in the liver to regulate SREBP1-controlled lipid homeostasis during feeding and diabetes. CRTC2 can disrupt SREBP1 processing and transport by competing with binding to a subunit of COPII. During feeding, mTOR signalling inhibits the action of CRTC2 on SREBP1 processing. Overexpression of a CRTC2 mutant defective for mTOR regulation improves the lipogenic program and insulin sensitivity in obese mice. Abnormal accumulation of triglycerides in the liver, caused in part by increased de novo lipogenesis, results in non-alcoholic fatty liver disease and insulin resistance 1 , 2 . Sterol regulatory element-binding protein 1 (SREBP1), an important transcriptional regulator of lipogenesis, is synthesized as an inactive precursor that binds to the endoplasmic reticulum (ER). In response to insulin signalling, SREBP1 is transported from the ER to the Golgi in a COPII-dependent manner, processed by proteases in the Golgi, and then shuttled to the nucleus to induce lipogenic gene expression 3 , 4 , 5 ; however, the mechanisms underlying enhanced SREBP1 activity in insulin-resistant obesity and diabetes remain unclear. Here we show in mice that CREB regulated transcription coactivator 2 (CRTC2) 6 functions as a mediator of mTOR 7 signalling to modulate COPII-dependent SREBP1 processing. CRTC2 competes with Sec23A, a subunit of the COPII complex 8 , to interact with Sec31A, another COPII subunit, thus disrupting SREBP1 transport. During feeding, mTOR phosphorylates CRTC2 and attenuates its inhibitory effect on COPII-dependent SREBP1 maturation. As hepatic overexpression of an mTOR-defective CRTC2 mutant in obese mice improved the lipogenic program and insulin sensitivity, these results demonstrate how the transcriptional coactivator CRTC2 regulates mTOR-mediated lipid homeostasis in the fed state and in obesity.

Metal–organic frameworks (MOFs) are promising candidates for room‐temperature hydrogen storage materials after modification, thanks to their ability to chemisorb hydrogen. However, the hydrogen adsorption strength of these modified MOFs remains insufficient to meet the capacity and safety requirements of hydrogen storage systems. To address this challenge, a highly defective framework material known as de‐MgMOF is prepared by gently annealing Mg‐MOF‐74. This material retains some of the crystal properties of the original Mg‐MOF‐74 and exhibits exceptional hydrogen storage capacity at above‐ambient temperatures. The MgO5 knots around linker vacancies in de‐MgMOF can adsorb a significant amount of dissociated and nondissociated hydrogen, with adsorption enthalpies ranging from −22.7 to −43.6 kJ mol−1, indicating a strong chemisorption interaction. By leveraging a spillover catalyst of Pt, the material achieves a reversible hydrogen storage capacity of 2.55 wt.% at 160 °C and 81 bar. Additionally, this material offers rapid hydrogen uptake/release, stable cycling, and convenient storage capabilities. A comprehensive techno‐economic analysis demonstrates that this material outperforms many other hydrogen storage materials at the system level for on‐board applications. A novel, highly defective Mg‐MOF‐74 is reported, featuring linker vacancies that enhance hydrogen chemisorption strength at neighboring MgO5 nodes. Consequently, defective metal‐organic framework (MOF) demonstrates the capacity to absorb significant amounts of dissociated and undissociated hydrogen at temperatures up to 160 °C. This approach is anticipated to expedite the utilization of MOFs in hydrogen storage applications.

Reactive capture integrates CO 2 capture and electrochemical conversion into CO — a key building block in the synthesis of industrial chemicals and fuels — avoiding costly regeneration steps and improving efficiency. Amino acid salt solutions, which offer rapid CO 2 capture, facile CO 2 release, O 2 tolerance, and low toxicity, are promising sorbents for reactive capture. However, we find that amino acids can adsorb to common CO-producing catalysts, covering the active sites and deactivating the catalyst, and that they bind less to nickel phthalocyanine (NiPc). Still, when tested for reactive capture systems — where CO 2 supply is inherently limited — NiPc’s performance is constrained by its weak CO 2 adsorption and activation. Here we develop a nickel molecular catalyst supported on carbon nanotubes with a conjugated NiPc framework that resists amino acid adsorption and a coordinatively unsaturated Ni-N 3 structure that promotes CO 2 adsorption and enhances CO selectivity. As a result, we achieve 94% CO Faradaic efficiency at 100 mA cm –2 with an energy efficiency of 42% and an energy cost of 25 GJ t CO –1 . Reactive capture bypasses CO 2 regeneration, enabling efficient CO production but with low Faradaic efficiency. The authors report a Ni–N 3 molecular catalyst that resists amino acid adsorption and promotes efficient CO production in amino-acid systems.

Hydrogen storage materials are the key to hydrogen energy utilization. However, current materials can hardly meet the storage capacity and/or operability requirements of practical applications. Here we report an advancement in hydrogen storage performance and related mechanism based on a hydrofluoric acid incompletely etched MXene, namely, a multilayered Ti 2 CT x (T is a functional group) stack that shows an unprecedented hydrogen uptake of 8.8 wt% at room temperature and 60 bar H 2 . Even under completely ambient conditions (25 °C, 1 bar air), Ti 2 CT x is still able to retain ~4 wt% hydrogen. The hydrogen storage is stable and reversible in the material, and the hydrogen release is controllable by pressure and temperature below 95 °C. The storage mechanism is deduced to be a nanopump-effect-assisted weak chemisorption in the sub-nanoscale interlayer space of the material. Such a storage approach provides a promising strategy for designing practical hydrogen storage materials. An incompletely etched Ti 2 CT x stack exhibits highly reversible hydrogen storage under near-ambient conditions by nanopump-effect-assisted weak chemisorption.

Substantial evidence suggests that phenolic extracts of Castanea mollissima spiny burs (CMPE) increase pancreatic cell viability after STZ (streptozotocin) treatment as a result of their antioxidant properties. In the present study, the hypoglycemic and hypolipidemic activities of CMPE were studied in normal and STZ-induced diabetic rats CMPE were orally administrated at doses of 150 and 300 mg/kg twice a day for 12 consecutive days. Serum glucose, triglyceride, total cholesterol, HDL- and LDL-cholesterol levels, malondialdehyde (MDA) level and SOD activity in liver, kidney, spleen and heart tissues were measured spectrophotometrically. In normal rats, no significant changes were observed in serum glucose, lipid profiles and tissue MDA and GSH levels after orally administration of CMPE. In diabetic rats, oral administration of CMPE at a dose of 300 mg/kg caused significant decreases in serum glucose, triglyceride, total cholesterol, LDL-cholesterol levels, as well as MDA and GSH levels in spleen and liver tissues. However, the 300 mg/kg dosage caused a significant body weight loss in both normal and diabetic rats. The observed effects indicated that CMPE could be further developed as a drug to prevent abnormal changes in blood glucose and lipid profile and to attenuate lipid peroxidation in liver and spleen tissues.

Non-precious metal catalysts (NPMCs) are promising low-cost alternatives of Pt/C for oxygen reduction reaction (ORR), which however suffer from serious stability challenge in the devices of proton-exchange-membrane fuel cells (PEMFC). Different from the traditional strategies of increasing the degree of graphitization of carbon substrates and using less Fenton-reactive metals, we prove here that proper regulation of coordination anions is also an effective way to improve the stability of NPMC. N/P co-coordinated Fe-Co dual-atomic-sites are constructed on ZIF-8 derived carbon support using a molecular precursor of C 34 H 28 Cl 2 CoFeP 2 and a “precursor-preselected” method. A composition of FeCoN 5 P 1 is infered for the dual-atom active site by microscopy and spectroscopy analysis. By comparing with N-coordinated references, we investigate the effect of P-coodination on the ORR catalysis of Fe-Co dual-atom catalysts in PEMFC. The metals in FeCoN 5 P 1 have the lower formation energy than those in the solo N-coordinated active sites of FeCoN 6 and FeN 4 , and exhibits a much better fuel cell stability. This anion approach provides a new way to improve the stability of dual-atom catalysts.

Divalent mercury ion (Hg 2+ ) is one of the most common pollutants in water with high toxicity and significant bioaccumulation, for which sensitive and selective detection methods are highly necessary to carry out its detection and quantification. Fluorescence detection by organic dyes is a simple and rapid method in pollutant analyses and is limited because of quenching caused by aggregation dye molecules. Hydrotalcite (LDH) is one of the most excellent carrier materials. In this study, an organic dye acridine orange (AO) was successfully loaded on the LDH layers, which significantly inhibited fluorescence quenching of AO. The composite AO/LDH reaches the highest fluorescence intensity when the AO initial concentration is 5 mg/L. With its enhanced fluorescent property, the composite powder was fabricated to fluorescence test papers. The maximal fluorescence intensity was achieved with a pulp to AO/LDH ratio of 1:5 which can be used to detect Hg 2+ in water by naked eyes. Hg 2+ in aqueous solution can be detected by instruments in the range of 0.5 to 150 mM. The novelty of this study lies on both the development of a new type of mineral-dye composite material, as well as its practical applications for fast detection.

Reactive capture integrates CO capture and electrochemical conversion into CO - a key building block in the synthesis of industrial chemicals and fuels - avoiding costly regeneration steps and improving efficiency. Amino acid salt solutions, which offer rapid CO capture, facile CO release, O tolerance, and low toxicity, are promising sorbents for reactive capture. However, we find that amino acids can adsorb to common CO-producing catalysts, covering the active sites and deactivating the catalyst, and that they bind less to nickel phthalocyanine (NiPc). Still, when tested for reactive capture systems - where CO supply is inherently limited - NiPc's performance is constrained by its weak CO adsorption and activation. Here we develop a nickel molecular catalyst supported on carbon nanotubes with a conjugated NiPc framework that resists amino acid adsorption and a coordinatively unsaturated Ni-N structure that promotes CO adsorption and enhances CO selectivity. As a result, we achieve 94% CO Faradaic efficiency at 100 mA cm with an energy efficiency of 42% and an energy cost of 25 GJ t .

Hydrogen storage materials are the key to hydrogen energy utilization. However, current materials can hardly meet the storage capacity and/or operability requirements of practical applications. Here we report an advancement in hydrogen storage performance and related mechanism based on a hydrofluoric acid incompletely etched MXene, namely, a multilayered Ti CT (T is a functional group) stack that shows an unprecedented hydrogen uptake of 8.8 wt% at room temperature and 60 bar H . Even under completely ambient conditions (25 °C, 1 bar air), Ti CT is still able to retain ~4 wt% hydrogen. The hydrogen storage is stable and reversible in the material, and the hydrogen release is controllable by pressure and temperature below 95 °C. The storage mechanism is deduced to be a nanopump-effect-assisted weak chemisorption in the sub-nanoscale interlayer space of the material. Such a storage approach provides a promising strategy for designing practical hydrogen storage materials.