A photoinduced flexible Li‐CO2 battery with well‐designed, hierarchical porous, and free‐standing In2S3@CNT/SS (ICS) as a bifunctional photoelectrode to accelerate both the CO2 reduction and ...evolution reactions (CDRR and CDER) is presented. The photoinduced Li‐CO2 battery achieved a record‐high discharge voltage of 3.14 V, surpassing the thermodynamic limit of 2.80 V, and an ultra‐low charge voltage of 3.20 V, achieving a round trip efficiency of 98.1 %, which is the highest value ever reported (<80 %) so far. These excellent properties can be ascribed to the hierarchical porous and free‐standing structure of ICS, as well as the key role of photogenerated electrons and holes during discharging and charging processes. A mechanism is proposed for pre‐activating CO2 by reducing In3+ to In+ under light illumination. The mechanism of the bifunctional light‐assisted process provides insight into photoinduced Li‐CO2 batteries and contributes to resolving the major setbacks of the system.
Battery life on Mars: A photoinduced flexible Li‐CO2 battery with hierarchical, porous, and free‐standing In2S3@CNT/SS as a bifunctional photoelectrode to accelerate both CO2 reduction and evolution is presented. The Li‐CO2 battery achieved a record‐high discharge voltage of 3.14 V (thermodynamic limit: 2.80 V), and an ultra‐low charge voltage of 3.20 V, and a roundtrip efficiency of 98.1 %.
Single atoms catalysts’ (SACs) applications in the energy storage field are hindered by their insufficient stability and poor recyclability due to their oxidation and agglomeration. To address this ...challenge, herein, a Co‐CMS composite material is synthesized by confining Co SACs into the highly ordered pores of the carbon molecular sieve (CMS). Related theoretical and experimental methods prove that the microporous trapping and hydroxyl doping of CMS are favorable for synergistically stabilizing the precursor and contributing to the subsequent conversion of single atoms with strong interactions between Co, O, and N. The unique 3D spiral pore structure of CMS facilitates the mass transfer of reactants and the highly dispersed Co single atoms confined in CMS increase the active sites. These properties are ideal for oxygen reduction reaction catalysts. Benefiting from the above‐mentioned superiority, the Co‐CMS cathode exhibits superior performance in a rechargeable Zn–air battery with a lower charge–discharge voltage gap of 0.77 V and a power density of 219 mW cm−2. The applications of Co‐CMS catalysts are also extended to other metal–air batteries in this work, which further highlights the advantages of carbon molecular sieves in stabilizing SACs materials.
A new strategy for using the confinement effect of hierarchical carbon molecular sieves (CMS) to stabilize single atoms is deeply studied. This strategy enables the fabrication of a satisfactory oxygen reduction reaction catalyst. The synergistic effect of the micropore capture effect and the hydroxyl group of CMS produce excellent results. The Co‐CMS catalyst displays promising applications in the field of metal–air batteries.
The photoassisted lithium–oxygen (Li–O2) system has emerged as an important direction for future development by effectively reducing the large overpotential in Li–O2 batteries. However, the ...advancement is greatly hindered by the rapidly recombined photoexcited electrons and holes upon the discharging and charging processes. Herein, a breakthrough is made in overcoming these challenges by developing a new magnetic and optical field multi‐assisted Li–O2 battery with 3D porous NiO nanosheets on the Ni foam (NiO/FNi) as a photoelectrode. Under illumination, the photogenerated electrons and holes of the NiO/FNi photoelectrode play a key role in reducing the overpotential during discharging and charging, respectively. By introducing the external magnetic field, the Lorentz force acts oppositely on the photogenerated electrons and holes, thereby suppressing the recombination of charge carriers. The magnetic and optical field multi‐assisted Li–O2 battery achieves an ultralow charge potential of 2.73 V, a high energy efficiency of 96.7%, and good cycling stability. This external magnetic and optical field multi‐assisted technology paves a new way of developing high‐performance Li–O2 batteries and other energy storage systems.
A renewable magnetic and optical field multi‐assisted Li–O2 battery is developed with porous NiO on the Ni foam as a photoelectrode. The battery achieves an ultralow charge potential of 2.73 V, a high energy efficiency of 96.7%, and good cycling stability. The effect mechanism of the improved battery performance with magnetic field and optical field is revealed.
Photoassisted electrochemical reaction is regarded as an effective approach to reduce the overpotential of lithium–oxygen (Li–O2) batteries. However, the achievement of both broadband absorption and ...long term battery cycling stability are still a formidable challenge. Herein, an oxygen vacancy‐mediated fast kinetics for a photoassisted Li–O2 system is developed with a silver/bismuth molybdate (Ag/Bi2MoO6) hybrid cathode. The cathode can offer both double advantages for light absorption covering UV to visible region and excellent electrochemical activity for O2. Upon discharging, the photoexcited electrons from Ag nanoplate based on the localized surface plasmon resonance (LSPR) are injected into the oxygen vacancy in Bi2MoO6. The fast oxygen reaction kinetics generate the amorphous Li2O2, and the discharge plateau is improved to 3.05 V. Upon charging, the photoexcited holes are capable to decompose amorphous Li2O2 promptly, yielding a very low charge plateau of 3.25 V. A first cycle round‐trip efficiency is 93.8% and retention of 70% over 500 h, which is the longest cycle life ever reported in photoassisted Li–O2 batteries. This work offers a general and reliable strategy for boosting the electrochemical kinetics by tailoring the crystalline of Li2O2 with wide‐band light.
A facile oxygen vacancy‐mediated fast kinetics for an ultrawide band photoassisted Li–O2 system is developed. The bifunctional Ag/Bi2MoO6 cathode is favorable to promoting the oxygen reduction reaction and oxygen evolution reaction kinetics due to the discharge products is amorphous Li2O2. The reaction mechanism is revealed by in situ X‐ray diffraction and Raman spectroscopy.
Directly converting and storing abundant solar energy in next‐generation energy storage devices is of central importance to build a sustainable society. Herein, a new prototype of a light‐promoted ...rechargeable and flexible Li‐CO2 battery with a TiO2/carbon cloth (CC) cathode is reported for the direct utilization of solar energy to promote the kinetics of the carbon dioxide reduction reaction and carbon dioxide evolution reaction (CO2ER). Under illumination, photoelectrons are generated in the conduction band of TiO2/CC, followed by the enhancing diffusion of electrons and lithium ions during the discharge process. The photoelectrons on the cathode surface can regulate the morphology of the discharge product Li2CO3, contributing to boosting the kinetics of the subsequent CO2ER process. In the reverse charge process, photogenerated holes can favor the decomposition of Li2CO3, leading to a negative charge potential of 2.88 V without increased polarization over ≈60 h of cycling. Owing to an ultralow overpotential of 0.06 V between the discharge and charge process, an ultrahigh energy efficiency of 97.9% is attained under illumination. The introduction of a light‐promoted flexible Li‐CO2 battery can pave the way toward developing the use of solar energy to address the charging overpotential of conventional Li‐CO2 batteries.
A renewable light‐promoted flexible Li‐CO2 battery is developed inspired by the photoenergy conversion and utilization concept. The utilization of solar light can effectively alleviate the charge polarization and promote the Li+ diffusion and mass transfer, resulting in considerable improvement of the kinetics of the carbon dioxide reduction reaction and carbon dioxide evolution reaction processes in the Li‐CO2 battery.
Li−CO2 batteries have received significant attention owing to their advantages of combining greenhouse gas utilization and energy storage. However, the high kinetic barrier between gaseous CO2 and ...the Li2CO3 product leads to a low operating voltage (<2.5 V) and poor energy efficiency. In addition, the reversibility of Li2CO3 has always been questioned owing to the introduction of more decomposition paths caused by its higher charging plateau. Here, a novel “trinity” Li−CO2 battery system was developed by synergizing CO2, soluble redox mediator (2,2,6,6‐tetramethylpiperidoxyl, as TEM RM), and reduced graphene oxide electrode to enable selective conversion of CO2 to Li2C2O4. The designed Li−CO2 battery exhibited an output plateau reaching up to 2.97 V, higher than the equilibrium potential of 2.80 V for Li2CO3, and an ultrahigh round‐trip efficiency of 97.1 %. The superior performance of Li−CO2 batteries is attributed to the TEM RM‐mediated preferential growth mechanism of Li2C2O4, which enhances the reaction kinetics and rechargeability. Such a unique design enables batteries to cope with sudden CO2‐deficient environments, which provides an avenue for the rationally design of CO2 conversion reactions and a feasible guide for next‐generation Li−CO2 batteries.
The “trinity” strategy provides a new perspective for the development of Li−CO2 batteries. The addition of a soluble mediator, TEM RM, was used to modulate the three‐phase interface and facilitate the conversion of CO2 to Li2C2O4. This strategy avoids a series of issues associated with the Li2CO3 product, contributing to excellent cycling performance for Li−CO2 battery.
Applying solar energy into energy storage battery systems is challenging in achieving green and sustainable development, however, the efficient progress of photo‐assisted metal–air batteries is ...restricted by the rapid recombination of photogenerated electrons and holes upon the photocathode. Herein, a 1D‐ordered MoS2 nanotube (MoS2‐ONT) with confined mass transfer can be used to extend the lifetime of photogenerated carriers, which is capable of overcoming the challenge of rapid recombination of electron and holes. The tubular confined space cannot only promote the orderly separation and migration of charge carriers but also realize the accumulation of charge and the rapid activation of oxygen molecules. The concave surface of MoS2‐ONT can improve the carrier separation ability and prolong the carrier lifetime. Meanwhile, the ordered tubular confined space can effectively realize the rapid transfer of charge, ion, and oxygen. Under light irradiation, a fast oxygen reduction reaction kinetics of 70 mW cm−2 for photo‐assisted Zn–air battery is achieved, which is the highest value reported for photo‐assisted Zn–air batteries. Significantly, the photo‐assisted Li–O2 battery based on MoS2‐ONT also shows superior rate capability and other exciting battery performance. This work shows the universality of the confined carrier separation strategy in photo‐assisted metal–air batteries.
Benefiting from the high photogenerated electron–hole separation efficiency and the inherent mass transfer characteristics of MoS2 confined nanotubes, the photo‐assisted Zn–air battery delivers a high power density (70 mW cm−2), and obtains a Li–O2 battery with excellent rate performance, which fully proves the universality of this confined structure to achieve simple, efficient and fast photogenerated carrier separation dynamics.
•lncRNA NEAT1 protects BMEC from OGD induced injury.•lncRNA NEAT1 facilitates angiogenesis in OGD induced BMEC.•lncRNA exhibits protective effect via targeting miR-377 and uprelating VEGFA, SIRT1, ...BCL-XL.
The present study was designed to investigate the mechanism by which lncRNA NEAT1 regulates survival and angiogenesis in oxygen-glucose deprivation (OGD)-induced brain microvascular endothelial cells (BMECs).
OGD-treated BMECs were used to mimic cerebral ischaemia in vitro. The expression of lncRNA NEAT1 and miR-377 and proteins including VEGFA, SIRT1, and BCL-XL were measured by real-time quantitative PCR (qRT-PCR) and western blot, respectively. Cell viability and caspase 3 activity of BMECs under different conditions were determined using MTT and caspase activity assays, respectively. Matrigel-based angiogenesis assays were employed to evaluate the effect of lncRNA NEAT1 on angiogenesis. A dual-luciferase reporter assay was used to validate direct binding of miR-377 to putative targets.
OGD exposure reduced the cell viability of BMECs. Upregulation of lncRNA NEAT1 and downregulation of miR-377 were also observed under OGD conditions. Knockdown of lncRNA NEAT1 inhibited angiogenesis and aggravated apoptosis in OGD-induced BMECs. Meanwhile, the expression level of miR-377 was upregulated while its downstream targets (VEGFA, SIRT1, and BCL-XL) were downregulated after lncRNA NEAT1 knockdown. Furthermore, miR-377 inhibited the angiogenesis and survival of OGD-induced BMECs. The expression of VEGFA, SIRT1, and BCL-XL were all attenuated by miR-377 overexpression. The dual-luciferase reporter assay proved miR-377 targeted the 3′ UTR sequences of lncRNA NEAT1, VEGFA, SIRT1, and BCL-XL.
lncRNA NEAT1 facilitated the survival and angiogenesis of OGD-induced BMECs via targeting miR-377 and promoting the expression of VEGFA, SIRT1, and BCL-XL, suggesting that lncRNA NEAT1 could be a promising target for cerebral ischaemia treatment.
Abstract
Rechargeable lithium−oxygen (Li−O
2
) batteries with high theoretical energy density are considered as promising candidates for portable electronic devices and electric vehicles, whereas ...their commercial application is hindered due to poor cyclic stability caused by the sluggish kinetics and cathode passivation. Herein, the intrinsic stress originated from the growth and decomposition of the discharge product (lithium peroxide, Li
2
O
2
) is employed as a microscopic pressure resource to induce the built‐in electric field, further improving the reaction kinetics and interfacial Lithium ion (Li
+
) transport during cycling. Piezopotential caused by the intrinsic stress‐strain of solid Li
2
O
2
is capable of providing the driving force for the separation and transport of carriers, enhancing the Li
+
transfer, and thus improving the redox reaction kinetics of Li−O
2
batteries. Combined with a variety of in situ characterizations, the catalytic mechanism of barium titanate (BTO), a typical piezoelectric material, was systematically investigated, and the effect of stress‐strain transformation on the electrochemical reaction kinetics and Li
+
interface transport for the Li−O
2
batteries is clearly established. The findings provide deep insight into the surface coupling strategy between intrinsic stress and electric fields to regulate the electrochemical reaction kinetics behavior and enhance the interfacial Li
+
transport for battery system.
High production cost of bioplastics polyhydroxyalkanoates (PHA) is a major obstacle to replace traditional petro-based plastics. To address the challenges, strategies towards upstream metabolic ...engineering and downstream fermentation optimizations have been continuously pursued. Given that the feedstocks especially carbon sources account up to a large portion of the production cost, it is of great importance to explore low cost substrates to manufacture PHA economically.
Escherichia coli was metabolically engineered to synthesize poly-3-hydroxybutyrate (P3HB), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB), and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) using acetate as a main carbon source. Overexpression of phosphotransacetylase/acetate kinase pathway was shown to be an effective strategy for improving acetate assimilation and biopolymer production. The recombinant strain overexpressing phosphotransacetylase/acetate kinase and P3HB synthesis operon produced 1.27 g/L P3HB when grown on minimal medium supplemented with 10 g/L yeast extract and 5 g/L acetate in shake flask cultures. Further introduction succinate semialdehyde dehydrogenase, 4-hydroxybutyrate dehydrogenase, and CoA transferase lead to the accumulation of P3HB4HB, reaching a titer of 1.71 g/L with a 4-hydroxybutyrate monomer content of 5.79 mol%. When 1 g/L of α-ketoglutarate or citrate was added to the medium, P3HB4HB titer increased to 1.99 and 2.15 g/L, respectively. To achieve PHBV synthesis, acetate and propionate were simultaneously supplied and propionyl-CoA transferase was overexpressed to provide 3-hydroxyvalerate precursor. The resulting strain produced 0.33 g/L PHBV with a 3-hydroxyvalerate monomer content of 6.58 mol%. Further overexpression of propionate permease improved PHBV titer and 3-hydroxyvalerate monomer content to 1.09 g/L and 10.37 mol%, respectively.
The application of acetate as carbon source for microbial fermentation could reduce the consumption of food and agro-based renewable bioresources for biorefineries. Our proposed metabolic engineering strategies illustrate the feasibility for producing polyhydroxyalkanoates using acetate as a main carbon source. Overall, as an abundant and renewable resource, acetate would be developed into a cost-effective feedstock to achieve low cost production of chemicals, materials, and biofuels.
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