on the redox chemistry of CO 2 , ideally following the equation 4Li + 3CO 2 ↔ 2Li 2 CO 3 + C with a theoretical energy density of 1876 Wh kg −1 . Li-CO 2 batteries represent a novel approach for the utilization of atmospheric CO 2 , and may potentially find applications where the CO 2 concentration is high, for example, in submarines or on Mars.Despite their great potential, many challenges would have to be overcome before Li-CO 2 batteries become a practical reality. The most serious one is the reversible electrochemical decomposition of Li 2 CO 3 at charge. It has been widely recognized from earlier Li-O 2 researches that the accumulation of Li 2 CO 3 on cathode from the parasitic reaction between CO 2 and Li 2 O 2 would passivate the electrode surface and gradually degrade the battery performance. [19][20][21][22] A high voltage (sometimes > 4.3 V versus Li/Li + ) is often required in order to decompose Li 2 CO 3 . Under such anodic potential, the electrolyte oxidation becomes significant. This problem escalates when it comes to Li-CO 2 batteries. We are in urgent need of efficient and robust cathode catalysts to facilitate the reversible Li 2 CO 3 formation and decomposition, promote the energy efficiency and enhance the cycle life. [14,15] Carbonaceous materials including pristine or doped graphene and carbon nanotubes were the first type of catalysts investigated for the Li-CO 2 application. [17,23,24] Despite the relative abundance and low cost, they generally fell short of expectations in terms of activity and stability. The charging overpotential was often observed to quickly rise with cycling. Very recently, Ru nanoparticles were revealed to promote Li 2 CO 3 decomposition: they lowered the charge voltage to 3.9 V and enabled an impressive cycle life. [16] Nevertheless, the high cost of Ru would obviously prohibit its large-scale application. It is therefore imperative to develop high-performance nonprecious metal-based cathode catalysts for Li-CO 2 batteries.One possible strategy is to search within the existing pool of catalyst materials for CO 2 reduction reaction (CO 2 RR) in aqueous solution. Even though the reaction pathways of CO 2 reduction in aqueous and aprotic media differ substantially, we believe that the knowledge accumulated on aqueous CO 2 RR can be used to inspire the Li-CO 2 research. Transition metal porphyrins and phthalocyanines have long been known for their CO 2 RR activities. [25,26] However, they are not naturally suited as the cathode catalyst of Li-CO 2 batteries owing to their Li-CO 2 batteries represent an attractive solution for electrochemical energy storage by utilizing atmospheric CO 2 as the energy carrier. However, their practical viability critically depends on the development of efficient and low-cost cathode catalysts for the reversible formation and decomposition of Li 2 CO 3 . Here, the great potential of a structurally engineered polymer is demonstrated as the cathode catalyst for rechargeable Li-CO 2 batteries. Conjugated cobalt polyphthalocyanine is prepared vi...

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Background Long-term incidences and baseline determinants of functional cure (HBsAg seroclearance) during entecavir (ETV) or tenofovir disoproxil fumarate (TDF) treatment are incompletely understood. Methods This is an international multicenter cohort study of treatment-naïve chronic hepatitis B (CHB) patients who initiated on ETV or TDF without baseline malignancy. Patients were observed for HBsAg seroclearance until death or loss to follow-up. We calculated the incidences and explored the baseline determinants of HBsAg seroclearance using competing risk regression. Results The analysis included 4,769 patients (median age, 50 years; 69.05% male), with a median follow-up of 5.16 years (26,614.47 person-years). HBsAg clearance occurred in 58 patients, yielding a 10-year cumulative incidence of 2.11% (95% CI, 1.54 -- 2.88%) and an annual rate of 0.22% (95% CI, 0.17--0.28%). Baseline predictors included low-level viremia with HBV DNA <2,000 IU/mL (adjusted sub-distribution HR [aSHR], 3.14; 95% CI, 1.80--5.49), elevated serum alanine aminotransferase (ALT) >200 U/L (aSHR, 3.68; 95% CI, 2.07--6.53), serum bilirubin (aSHR, 1.11 per mg/dL; 95% CI, 1.06--1.17), and fatty liver (aSHR, 1.84; 95% CI, 1.03--3.29). Conclusion HBsAg seroclearance rarely occurs in CHB patients treated with ETV or TDF and is associated with low-level viremia, ALT flare, bilirubin level, and fatty liver.

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