查看更多>>摘要：Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid electrolyte interface(SEI),which induce low energy,short cycling life,and poor rate prop-erties.To address these drawbacks of SiO,we achieve in-situ construction of robust and fast-ion conduct-ing F,N-rich SEI layer on prelithiated micro-sized SiO(P-μSiO)via the simple and continuous treatment of μSiO in mild lithium 4,4'-dimethylbiphenyl solution and nonflammable hexafluorocyclotriphosp-hazene solution.Chemical prelithiation eliminates irreversible capacity through pre-forming inactive lithium silicates.Meanwhile,the symbiotic F,N-rich SEI with good mechanical stability and fast Li+per-meability is conductive to relieve volume expansion of μSiO and boost the Li+diffusion kinetics.Consequently,the P-μSiO realizes an impressive electrochemical performance with an elevated ICE of 99.57％and a capacity retention of 90.67％after 350 cycles.Additionally,the full cell with P-μSiO anode and commercial LiFePO4 cathode displays an ICE of 92.03％and a high reversible capacity of 144.97 mA h g-1.This work offers a general construction strategy of robust and ionically conductive SEI for advanced LIBs.
查看更多>>摘要：Urea oxidation reaction(UOR)is proposed as an exemplary half-reaction in renewable energy applica-tions because of its low thermodynamical potential.However,challenges persist due to sluggish reaction kinetics and complex by-products separation.To this end,we introduce the lattice oxygen oxidation mechanism(LOM),propelling a novel UOR route using a modified CoFe layered double hydroxide(LDH)catalyst termed CFRO-7.Theoretical calculations and in-situ characterizations highlight the acti-vated lattice oxygen(OL)within CFRO-7 as pivotal sites for UOR,optimizing the reaction pathway and accelerating the kinetics.For the urea overall electrolysis application,the LOM route only requires a low voltage of 1.54 V to offer a high current of 100 mA cm-2 for long-term utilization(＞48 h).Importantly,the by-product NCO-is significantly suppressed,while the CO2/N2 separation is efficiently achieved.This work proposed a pioneering paradigm,invoking the LOM pathway in urea electrolysis to expedite reaction dynamics and enhance product selectivity.
查看更多>>摘要：Rational design of photocatalyst to maximize the use of sunlight is one of the issues to be solved in pho-tocatalysis technology.In this study,the CuFe2O4@C/Cd0.9Zn0.1S(CFO@C/CZS)S-scheme photocatalyst with photothermal effect was synthesized by ultrasonic self-assembly combined with calcination.The dark CFO@C absorbed visible light and partly converted into heat to promote the hydrogen evolution reaction.The presence of heterojunctions inhibited the photogenerated electron-hole recombination.The graphite-carbon layer provided a stable channel for electron transfer,and the presence of magnetic CFO made recycle easier.Under the action of photothermal assistance and heterojunction,the hydrogen evolution rate of the optimal CFO@C/CZS was 80.79 mmol g-1 h-1,which was 2.55 times and 260.61 times of that of pure CZS and CFO@C,respectively.Notably,the composite samples also exhibit excellent stability and a wide range of environmental adaptability.Through experimental tests and first-principles simulation calculation methods,the plausible mechanism of photoactivity enhancement was proposed.This work provided a feasible strategy of photothermal assistance for the development of heterojunction photocatalysts with distinctive hydrogen evolution.
查看更多>>摘要：The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich lay-ered cathode(LLO)materials inherently excel.However,these materials face practical challenges,such as low initial Coulombic efficiency,inferior cycle/rate performance,and voltage decline during cycling,which limit practical application.Our study introduces a surface multi-component integration strategy that incorporates oxygen vacancies into the pristine LLO material Li1.2Mn0.6Ni0.2O2.This process involves a brief citric acid treatment followed by calcination,aiming to explore rate-dependent degradation behavior.The induced surface oxygen vacancies can reduce surface oxygen partial pressure and diminish the generation of O2 and other highly reactive oxygen species on the surface,thereby facilitating the acti-vation of Li ions trapped in tetrahedral sites while overcoming transport barriers.Additionally,the forma-tion of a spinel-like phase with 3D Li+diffusion channels significantly improves Li+diffusion kinetics and stabilizes the surface structure.The optimally modified sample boasts a discharge capacity of 299.5 mA h g-1 at a 0.1 C and 251.6 mA h g-1 at a 1 C during the initial activation cycle,with an impres-sive capacity of 222.1 mA h g-1 at a 5 C.Most notably,it retained nearly 70％of its capacity after 300 cycles at this elevated rate.This straightforward,effective,and highly viable modification strategy pro-vides a crucial resolution for overcoming challenges associated with LLO materials,making them more suitable for practical application.
查看更多>>摘要：In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic perfor-mance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb2+ions through host-guest complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved excep-tional power conversion efficiency(PCE),notably 21.7％for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photolumines-cence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb2+ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85％relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications.
查看更多>>摘要：The earth-abundant and high-performance catalysts are crucial for commercial implementation of hydro-gen evolution reaction(HER).Herein,a multifunctional site strategy to construct excellent HER catalysts by incorporating iridium(Ir)ions on the atomic scale into orthorhombic-CoSe2(lr-CoSe2)was reported.Outstanding hydrogen evolution activity in alkaline media such as a low overpotential of 48.7 mV at a current density of 10 mA cm-2 and better performance than commercial Pt/C catalysts at high current densities were found in the Ir-CoSe2 samples.In the experiments and theoretical calculations,it was revealed that Ir enabled CoSe2 to form multifunctional sites to synergistically catalyze alkaline HER by promoting the adsorption and dissociation of H2O(Ir sites)and optimizing the binding energy for H*on Co sites.It was noticeable that the electrolytic system comprising the Ir-CoSe2 electrode not only pro-duced hydrogen efficiently via HER,but also degraded organic pollutants(Methylene blue).The cell volt-age of the dual-function electrolytic system was 1.58 V at the benchmark current density of 50 mA cm-2,which was significantly lower than the conventional water splitting voltage.It was indicated that this method was a novel strategy for designing advanced HER electrocatalysts by constructing multifunc-tional catalytic sites for hydrogen production and organic degradation.
查看更多>>摘要：Photocatalytic reduction of CO2 into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate and retarded desorption of target products.Engineering the interface microenvironment of catalysts has been proposed as a strategy to exert a significant influence on reaction outcomes,yet it remains a signif-icant challenge.In this study,amino alkylation was successfully integrated into the melem unit of poly-meric carbon nitrides(PCN),which could efficiently drive the photocatalytic CO2 reduction.Experimental characterization and theoretical calculations revealed that the introduction of amino alkylation lowers the energy barrier for CO2 reduction into*COOH intermediate,transforming the adsorption of*COOH intermediate from the endothermic to an exothermic process.Notably,the as-prepared materials demon-strated outstanding performance in photocatalytic CO2 reduction,yielding CO at a rate of 152.8 μmol h-1 with a high selectivity of 95.4％and a quantum efficiency of 6.6％.
Anna M.BeilerWenhui LiAlisa DenisiukEmilio Palomares...
292-295页
查看更多>>摘要：For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H2 fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxi-dize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N2 and H2 in a 1:2.9 ratio with 89％faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.
Benjamin Flei?Juraj PriscakMartin HammerschmidJosef Fuchs...
296-310页
查看更多>>摘要：Chemical looping combustion has the potential to be an efficient and low-cost technology capable of con-tributing to the reduction of the atmospheric concentration of CO2 in order to reach the 1.5/2 ℃ goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO2 via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic compar-ison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was con-ducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4％and carbon capture rates up to 98.5％were reached.The techno-economic assessment resulted in CO2 capture costs of 75 and 40 6/tCO2 for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the produc-tion process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO2 could be reduced by implementing the chemical looping combustion technology.
查看更多>>摘要：Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associ-ated with low efficiency and harsh reaction conditions.Here,we have successfully synthesized a novel bifunctional Ru-WOx-MgOy catalyst through a facile'one-pot'solvothermal method.Remarkably,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction conditions.The yield of 1,2-PDO is up to 56.2％at 140 ℃ for 4 h under an ultra-low hydrogen pressure of only 0.2 MPa,surpassing the reported results in recent literature(below 51％).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the pres-ence of oxygen vacancies in the Ru-WOx-MgOy catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO.
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