With the rapidly increasing interests on wearable electronics over the past decades, the limited energy density and nondeformable configuration of conventional 2D lithium-ion batteries (LIBs) have already become the dominant obstacles that are hindering the roads of wearable consumer electronics toward ubiquity. [1][2][3][4][5] Hence, it is urgent to develop an alternative highperformance flexible energy storage device to break through the inherent restrictions of rigid LIBs. [6][7][8] The Li-CO 2 battery, a newly conceptual metal-gas battery, has been considered as a promising candidate for the next-generation high-performance electrochemical energy storage system recently. [9,10] It possesses a high theoretical energy density via the four-electrons transfer reaction (4Li + + 3CO 2 + 4e − → 2Li 2 CO 3 + C, E° = 2.80 V vs Li + /Li) and provides a novel environmentally friendly approach to CO 2 fixing which is of great benefit to alleviate global warming. [11][12][13] Interestingly, the Li-CO 2 battery is also very attractive for aerospace exploration; for example, it may be a possible energy system for providing electricity on Mars where the atmosphere consists of 96% CO 2 gas. [14] In spite of the aforementioned favorable factors, very few reports in the literature related to flexible Li-CO 2 battery devices for wearable electronics have been reported so far. After systematical investigations, it is found that the main challenges of fabricating high-performance flexible Li-CO 2 battery devices lie in the following three aspects: (1) carbon nanophases (e.g., Ketjenblack, [9,10,15] CNTs, [11,16] graphene [17,18] ), which dominate those known Li-CO 2 battery catalysts, induce the formation of Li 2 CO 3 , a wide-bandgap insulator. [19,20] It results in a sluggish kinetics for CO 2 evolution so that a high charge potential of 4.2-4.6 V was commonly required to drive the degradation of Li 2 CO 3 in most previous Li-CO 2 batteries. [10,11,17] Such high potential not only increases the risk of electrolyte decomposition but also accelerates the oxidation of electrodes. [21,22] Meanwhile, originated from the incomplete decomposition, more and more solid carbonate species accumulated in the surface of cathode during cycling, leading to a distinct decrease on catalytic performance and even the rapid extension of impedance up to a "sudden death" of the battery. [20,23,24] Consequently, the majority of those reported Li-CO 2 batteries showed a negligibleThe rapid development of wearable electronics requires a revolution of power accessories regarding flexibility and energy density. The Li-CO 2 battery was recently proposed as a novel and promising candidate for nextgeneration energy-storage systems. However, the current Li-CO 2 batteries usually suffer from the difficulties of poor stability, low energy efficiency, and leakage of liquid electrolyte, and few flexible Li-CO 2 batteries for wearable electronics have been reported so far. Herein, a quasi-solidstate flexible fiber-shaped Li-CO 2 battery with low overpotential and ...

The Li-CO 2 battery is a promising energy storage device for wearable electronics due to its long discharge plateau, high energy density, and environmental friendliness. However, its utilization is largely hindered by poor cyclability and mechanical rigidity due to the lack of a flexible and durable catalyst electrode. Herein, flexible fiber-shaped Li-CO 2 batteries with ultralong cycle-life, high rate capability, and large specific capacity are fabricated, employing bamboo-like N-doped carbon nanotube fiber (B-NCNT) as flexible, durable metal-free catalysts for both CO 2 reduction and evolution reactions. Benefiting from high N-doping with abundant pyridinic groups, rich defects, and active sites of the periodic bamboo-like nodes, the fabricated Li-CO 2 battery shows outstanding electrochemical performance with high fulldischarge capacity of 23 328 mAh g −1 , high rate capability with a low potential gap up to 1.96 V at a current density of 1000 mA g −1 , stability over 360 cycles, and good flexibility. Meanwhile, the bifunctional B-NCNT is used as the counter electrode for a fiber-shaped dye-sensitized solar cell to fabricate a self-powered fiber-shaped Li-CO 2 battery with overall photochemicalelectric energy conversion efficiency of up to 4.6%. Along with a stable voltage output, this design demonstrates great adaptability and application potentiality in wearable electronics with a breath monitor as an example.

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BackgroundAssessment and characterization of human colon microbiota is now a major research area in human diseases, including in patients with hepatitis B liver cirrhosis (HBLC).MethodsWe recruited 120 patients with HBLC and 120 healthy controls. The fecal microbial community and functions in the two groups were analyzed using high-throughput Solexa sequencing of the complete metagenomic DNA and bioinformatics methods.ResultsCommunity and metabolism-wide changes of the fecal microbiota in 20 HBLC patients and 20 healthy controls were observed and compared. A negative correlation was observed between the Child-Turcotte-Pugh scores and Bacteroidetes (P < 0.01), whereas a positive correlation was observed between the scores and Enterobacteriaceae and Veillonella (P < 0.01). Analysis of the additional 200 fecal microbiota samples demonstrated that these intestinal microbial markers might be useful for distinguishing liver cirrhosis microbiota samples from normal ones. The functional diversity was significantly reduced in the fecal microbiota of cirrhotic patients compared with in the controls. At the module or pathway levels, the fecal microbiota of the HBLC patients showed enrichment in the metabolism of glutathione, gluconeogenesis, branched-chain amino acid, nitrogen, and lipid (P < 0.05), whereas there was a decrease in the level of aromatic amino acid, bile acid and cell cycle related metabolism (P < 0.05).ConclusionsExtensive differences in the microbiota community and metabolic potential were detected in the fecal microbiota of cirrhotic patients. The intestinal microbial community may act as an independent organ to regulate the body’s metabolic balance, which may affect the prognosis for HBLC patients.