A Hydrogel Electrolyte with High Adaptability over a Wide Temperature Range and Mechanical Stress for Long-Life Flexible Zinc-Ion Batteries.

Flexible zinc-ion batteries have garnered significant attention in the realm of wearable technology. However, the instability of hydrogel electrolytes in a wide-temperature range and uncontrollable side reactions of the Zn electrode have become the main problems for practical applications. Herein, N,N-dimethylformamide (DMF) to design a binary solvent (H2 O-DMF) is introduced and combined it with polyacrylamide (PAM) and ZnSO4 to synthesize a hydrogel electrolyte (denoted as PZD). The synergistic effect of DMF and PAM not only guides Zn2+ deposition on Zn(002) crystal plane and isolates H2 O from the Zn anode, but also breaks the hydrogen bonding network between water to improve the wide-temperature range stability of hydrogel electrolytes. Consequently, the symmetric cell utilizing PZD can stably cycle over 5600 h at 0.5 mA cm- 2 @0.5 mAh cm-2 . Furthermore, the Zn//PZD//MnO2 full cell exhibits favorable wide-temperature range adaptability (for 16000 cycles at 3 A g-1 under 25 °C, 750 cycles with 98 mAh g-1 at 0.1 A g-1 under -20 °C) and outstanding mechanical properties (for lighting up the LEDs under conditions of pressure, bending, cutting, and puncture). This work proposes a useful modification for designing a high-performance hydrogel electrolyte, which provides a reference for investigating the practical flexible aqueous batteries.

Adaptive Ionization-Induced Tunable Electric Double Layer for Practical Zn Metal Batteries over Wide pH and Temperature Ranges.

The violent side reactions of Zn metal in aqueous electrolyte lead to sharp local-pH fluctuations at the interface, which accelerate Zn anode breakdown; thus, the development of an optimization strategy to accommodate a wide pH range is particularly critical for improving aqueous Zn metal batteries. Herein, we report a pH-adaptive electric double layer (EDL) tuned by glycine (Gly) additive with pH-dependent ionization, which exhibits excellent capability to stabilize Zn anodes in wide-pH aqueous electrolytes. It is discovered that a Gly-ionic EDL facilitates the directed migration of charge carriers in both mildly acidic and alkaline electrolytes, leading to the successful suppression of local saturation. It is worth mentioning that the regulation effect of the additive concentration on the inner Helmholtz plane (IHP) structure of Zn electrodes is clarified in depth. It is revealed that the Gly additives without dimerization can develop orderly and dense vertical adsorption within the IHP to effectively reduce the EDL repulsive force of Zn2+ and isolate H2O from the anode surface. Consequently, they Zn anode with tunable EDL exhibits superior electrochemical performance in a wide range of pH and temperature, involving the prodigious cycle reversibility of 7000 h at Zn symmetric cells with ZnSO4-Gly electrolytes and an extended lifespan of 50 times in Zn symmetric cells with KOH-Gly electrolytes. Moreover, acidic Zn powder||MnO2 pouch cells, and alkaline high-voltage Zn||Ni0.8Co0.1Mn0.1O2 cells, and Zn||NiCo-LDH cells also deliver excellent cycling reversibility. The tunable EDL enables the ultrahigh depth of discharge (DOD) of 93%. This work elucidates the design of electrolyte additives compatible in a wide range of pH and temperature, which might cause inspiration in the fields of practical multiapplication scenarios for Zn anodes.

Progressive activation of porous vanadium nitride microspheres with intercalation-conversion reactions toward high performance over a wide temperature range for zinc-ion batteries.

Rechargeable aqueous zinc-ion batteries have great promise for becoming next-generation storage systems, although the irreversible intercalation of Zn2+ and sluggish reaction kinetics impede their wide application. Therefore, it is urgent to develop highly reversible zinc-ion batteries. In this work, we modulate the morphology of vanadium nitride (VN) with different molar amounts of cetyltrimethylammonium bromide (CTAB). The optimal electrode has porous architecture and excellent electrical conductivity, which can alleviate volume expansion/contraction and allow for fast ion transmission during the Zn2+ storage process. Furthermore, the CTAB-modified VN cathode undergoes a phase transition that provides a better framework for vanadium oxide (VOx). With the same mass of VN and VOx, VN provides more active material after phase conversion due to the molar mass of the N atom being less than that of the O atom, thus increasing the capacity. As expected, the cathode displays an excellent electrochemical performance of 272 mAh g-1 at 5 A g-1, high cycling stability up to 7000 cycles, and excellent performance over a wide temperature range. This discovery creates new possibilities for the development of high-performance multivalent ion aqueous cathodes with rapid reaction mechanisms.

Metabolic and Transcriptomic Profiling Reveals Etiolated Mechanism in Huangyu Tea (Camellia sinensis) Leaves.

Leaf color is one of the key factors involved in determining the processing suitability of tea. It relates to differential accumulation of flavor compounds due to the different metabolic mechanisms. In recent years, photosensitive etiolation or albefaction is an interesting direction in tea research field. However, the molecular mechanism of color formation remains unclear since albino or etiolated mutants have different genetic backgrounds. In this study, wide-target metabolomic and transcriptomic analyses were used to reveal the biological mechanism of leaf etiolation for 'Huangyu', a bud mutant of 'Yinghong 9'. The results indicated that the reduction in the content of chlorophyll and the ratio of chlorophyll to carotenoids might be the biochemical reasons for the etiolation of 'Huangyu' tea leaves, while the content of zeaxanthin was significantly higher. The differentially expressed genes (DEGs) involved in chlorophyll and chloroplast biogenesis were the biomolecular reasons for the formation of green or yellow color in tea leaves. In addition, our results also revealed that the changes of DEGs involved in light-induced proteins and circadian rhythm promoted the adaptation of etiolated tea leaves to light stress. Variant colors of tea leaves indicated different directions in metabolic flux and accumulation of flavor compounds.

A Comprehensive Review on Beneficial Effects of Catechins on Secondary Mitochondrial Diseases.

Mitochondria are the main sites for oxidative phosphorylation and synthesis of adenosine triphosphate in cells, and are known as cellular power factories. The phrase "secondary mitochondrial diseases" essentially refers to any abnormal mitochondrial function other than primary mitochondrial diseases, i.e., the process caused by the genes encoding the electron transport chain (ETC) proteins directly or impacting the production of the machinery needed for ETC. Mitochondrial diseases can cause adenosine triphosphate (ATP) synthesis disorder, an increase in oxygen free radicals, and intracellular redox imbalance. It can also induce apoptosis and, eventually, multi-system damage, which leads to neurodegenerative disease. The catechin compounds rich in tea have attracted much attention due to their effective antioxidant activity. Catechins, especially acetylated catechins such as epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), are able to protect mitochondria from reactive oxygen species. This review focuses on the role of catechins in regulating cell homeostasis, in which catechins act as a free radical scavenger and metal ion chelator, their protective mechanism on mitochondria, and the protective effect of catechins on mitochondrial deoxyribonucleic acid (DNA). This review highlights catechins and their effects on mitochondrial functional metabolic networks: regulating mitochondrial function and biogenesis, improving insulin resistance, regulating intracellular calcium homeostasis, and regulating epigenetic processes. Finally, the indirect beneficial effects of catechins on mitochondrial diseases are also illustrated by the warburg and the apoptosis effect. Some possible mechanisms are shown graphically. In addition, the bioavailability of catechins and peracetylated-catechins, free radical scavenging activity, mitochondrial activation ability of the high-molecular-weight polyphenol, and the mitochondrial activation factor were also discussed.

Sb-Doped metallic 1T-MoS2 nanosheets embedded in N-doped carbon as high-performance anode materials for half/full sodium/potassium-ion batteries.

Metal 1T phase molybdenum disulfide (1T-MoS2) is being actively considered as a promising anode due to its high conductivity, which can improve electron transfer. Herein, we elaborately designed stable Sb-doped metallic 1T phase molybdenum sulfide (1T-MoS2-Sb) with a few-layered nanosheet structure via a simple calcination technique. The N-doping of the carbon and Sb-doping induce the formation of T-phase MoS2, which not only effectively enhances the entire stability of the structure, but also improves its cycling performance and stability. When employed as an anode of sodium-ion batteries (SIBs), 1T-MoS2-Sb exhibits a reversible capacity of 493 mA h g-1 at 0.1 A g-1 after 100 cycles and delivers prominent long-term performance (253 mA h g-1 at 1 A g-1 after 2200 cycles) along with decent rate capability. Paired with a Na3V2(PO4)3 cathode, it displays a superior capacity of 242 mA h g-1 at 0.5 A g-1 over 100 cycles, which is one of the best performances of a MoS2-based full cell for SIBs. Employed as the anode for potassium-ion batteries (PIBs), it exhibits a satisfactory specific capacity of 343 mA h g-1 at 0.1 A g-1 after 100 cycles. This facile strategy will provide new insights for designing T-phase advanced anode materials for SIBs/PIBs.

High-Rate, Large Capacity, and Long Life Dendrite-Free Zn Metal Anode Enabled by Trifunctional Electrolyte Additive with a Wide Temperature Range.

Aqueous Zn-ion batteries (AZIBs) have been recognized as promising energy storage devices due to their high theoretical energy density and cost-effectiveness. However, side reactions and Zn dendrite generation during cycling limit their practical application. Herein, ammonium acetate (CH3 COONH4 ) is selected as a trifunctional electrolyte additive to enhance the electrochemical performance of AZIBs. Research findings show that NH4 + (oxygen ligand) and CH3 COO- (hydrogenligand) with preferential adsorption on the Zn electrode surface can not only hinder Zn anode directly contact with active H2 O, but also regulate the pH value of the electrolyte, thus suppressing the parasitic reactions. Additionally, the formed SEI is mainly consisted of Zn5 (CO3 )2 (OH)6 with a high Zn2+ transference number, which could achieve a dendrite-free Zn anode by homogenizing Zn deposition. Consequently, the Zn||Zn symmetric batteries with CH3 COONH4 -based electrolyte can operate steadily at an ultrahigh current density of 40 mA cm-2 with a cumulative capacity of 6880 mAh cm-2 , especially stable cycling at -10 °C. The assembled Zn||MnO2 full cell and Zn||activated carbon capacitor also deliver prominent electrochemical reversibility. This work provides unique understanding of designing multi-functional electrolyte additive and promotes a long lifespan at ultrahigh current density for AZIBs.

Structure Engineering of BiSbSx Nanocrystals Embedded within Sulfurized Polyacrylonitrile Fibers for High Performance of Potassium-Ion Batteries.

Potassium-ion batteries (PIBs) are regarded as promising candidates in next-generation energy storage technology; however, the electrode materials in PIBs are usually restricted by the shortcomings of large volume expansion and poor cycling stability stemming from a high resistance towards diffusion and insertion of large-sized K ions. In this study, BiSbSx nanocrystals are rationally integrated with sulfurized polyacrylonitrile (SPAN) fibres through electrospinning technology with an annealing process. Such a unique structure, in which BiSbSx nanocrystals are embedded inside the SPAN fibre, affords multiple binding sites and a short diffusion length for K+ to realize fast kinetics. In addition, the molecular structure of SPAN features robust chemical interactions for stationary diffluent discharge products. Thus, the electrode demonstrates a superior potassium storage performance with an excellent reversible capacity of 790 mAh g-1 (at 0.1 A g-1 after 50 cycles) and 472 mAh g-1 (at 1 A g-1 after 2000 cycles). It's one of the best performances for metal dichalcogenides anodes for PIBs to date. The unusual performance of the BiSbSx @SPAN composite is attributed to the synergistic effects of the judicious nanostructure engineering of BiSbSx nanocrystals as well as the chemical interaction and confinement of SPAN fibers.

Integration of Metabolome and Transcriptome Reveals the Relationship of Benzenoid-Phenylpropanoid Pigment and Aroma in Purple Tea Flowers.

Tea (Camellia sinensis) flowers are normally white, even though the leaves could be purple. We previously discovered a specific variety with purple leaves and flowers. In the face of such a phenomenon, researchers usually focus on the mechanism of color formation but ignore the change of aroma. The purple tea flowers contain more anthocyanins, which belong to flavonoids. Meanwhile, phenylalanine (Phe), derived from the shikimate pathway, is a precursor for both flavonoids and volatile benzenoid-phenylpropanoids (BPs). Thus, it is not clear whether the BP aroma was attenuated for the appearance of purple color. In this study, we integrated metabolome and transcriptome of petals of two tea varieties, namely, Zijuan (ZJ) with white flowers and Baitang (BT) with purple flowers, to reveal the relationship between color (anthocyanins) and aroma (volatile BPs). The results indicated that in purple petals, the upstream shikimate pathway promoted for 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS) was elevated. Among the increased anthocyanins, delphinidin-3-O-glucoside (DpG) was extremely higher; volatile BPs, including benzyl aldehyde, benzyl alcohol, acetophenone (AP), 1-phenylethanol, and 2-phenylethanol, were also enhanced, and AP was largely elevated. The structural genes related to the biosynthesis of volatile BPs were induced, while the whole flavonoid biosynthesis pathway was downregulated, except for the genes flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H), which were highly expressed to shift the carbon flux to delphinidin, which was then conjugated to glucoside by increased bronze-1 (BZ1) (UDP-glucose: flavonoid 3-O-glucosyltransferase) to form DpG. Transcription factors (TFs) highly related to AP and DpG were selected to investigate their correlation with the differentially expressed structural genes. TFs, such as MYB, AP2/ERF, bZIP, TCP, and GATA, were dramatically expressed and focused on the regulation of genes in the upstream synthesis of Phe (DAHPS; arogenate dehydratase/prephenate dehydratase) and the synthesis of AP (phenylacetaldehyde reductase; short-chain dehydrogenase/reductase), Dp (F3'H; F3'5'H), and DpG (BZ1), but inhibited the formation of flavones (flavonol synthase) and catechins (leucoanthocyanidin reductase). These results discovered an unexpected promotion of volatile BPs in purple tea flowers and extended our understanding of the relationship between the BP-type color and aroma in the tea plant.

A Comparative Metabolomic Analysis Reveals Difference Manufacture Suitability in "Yinghong 9" and "Huangyu" Teas (Camellia sinensis).

"Yinghong 9" is a widely cultivated large-leaf variety in South China, and the black tea made from it has a high aroma and strong sweet flavor. "Huangyu" is a light-sensitive tea variety with yellow leaves. It was cultivated from the bud-mutation of "Yinghong 9" and has a very low level of chlorophyll during young shoot development. Due to chlorophyll being involved in carbon fixation and assimilation, the changes in photosynthesis might potentially affect the accumulation of flavor metabolites, as well as the quality of "Huangyu" tea. Although "Huangyu" has a golden yellow color and high amino acid content, the mechanism underlying the formation of leaf color and drinking value remains unclear. The widely targeted metabolomics and GC-MS analysis were performed to reveal the differences of key metabolites in fresh and fermented leaves between "Yinghong 9" and "Huangyu." The results showed that tea polyphenols, total chlorophyll, and carotenoids were more abundant in "Yinghong 9." Targeted metabolomics analysis indicated that kaempferol-3-glycoside was more abundant in "Yinghong 9," while "Huangyu" had a higher ratio of kaempferol-3-glucoside to kaempferol-3-galactoside. Compared with "Yinghong 9" fresh leaves, the contents of zeaxanthin and zeaxanthin palmitate were significantly higher in "Huangyu." The contents of α-farnesene, ß-cyclocitral, nerolidol, and trans-geranylacetone, which were from carotenoid degradation and involved in flowery-fruity-like flavor in "Huangyu" fermented leaves, were higher than those of "Yinghong 9." Our results indicated that "Huangyu" was suitable for manufacturing non-fermented tea because of its yellow leaf and flowery-fruity-like compounds from carotenoid degradation.

Facile fabrication of WS2 nanocrystals confined in chlorella-derived N, P co-doped bio-carbon for sodium-ion batteries with ultra-long lifespan.

Sodium-ion batteries (SIBs) have been regarded as a promising substitute for lithium-ion batteries but there are still formidable challenges in developing an anode material with adequate lifespan and outstanding rate performance. Transition metal dichalcogenides (TMDs) are promising anode materials for SIBs due to their high theoretical capacities. However, their severe volume expansions and low electronic conductivity impede their practical developments. In addition, the synthesis of energy storage materials from waste biomass has aroused extensive attention. Herein, we synthesize WS2 nanocrystals embedded in N and P co-doped biochar via a facile bio-sorption followed by sulphurization, employing waste chlorella as the adsorbent and bio-reactor. The WS2 nanocrystals are beneficial for storing more sodium ions and expediting the transportation of sodium ions, thus improving the capacity and reaction kinetics. Chlorella acts as a reactor and not only inhibits the stacking of WS2 nanocrystals during the synthesis process but also alleviates the mechanical pressure of composite during the charge/discharge process. As a result, the WS2/NPC-2 electrode delivers a high specific capacity (436 mA h g-1 at 0.1 A g-1) and superior rate performance of 311 mA h g-1 at 3 A g-1 for SIBs. It also exhibits excellent stability even up to 6000 cycles at 5 A g-1, which is one of the optimal long-cycle properties reported for WS2-based materials to date.

Silver-mediated three-component cycloaddition reaction for direct synthesis of 1-N-vinyl-substituted 1,2,3-triazoles.

Herein, we report direct synthesis of 1-N-vinyl-1,2,3-triazoles via silver-mediated three-component cycloaddition reaction of phenylacetylenes, trimethylsilylazide, and 1,3-dicarbonyl compounds. The synthetic protocol proceeds with operational simplicity, good substrate and functional group compatibility, and easily available feedstocks, and without the need for pre-installation of vinylazide precursors, and offers a practical method for the efficient elaboration of triazole derivatives.