Efficiency of high-loaded nickel catalysts modified by Mg in hydrogen storage/extraction using quinoline/decahydroquinoline pair as LOHC substrates

An effect of Mg introduction on efficiency of high-loaded nickel catalysts in dehydrogenation of decahydroquinoline(10HQ)was inves-tigated.10HQ dehydrogenation is key process for the liquid organic hydrogen carrier(LOHC)storage technology using the quinoline/10HQ pair as H_(2)-lean/H_(2)-rich substrates.An influence of synthesis technique of Ni/Mg/Al catalysts on their properties has been demonstrated.The catalysts were synthesized through coprecipitation of Ni,Mg,Al precursors to obtain layered double hydroxides(LDH)or via syn-thesis of(∼72 wt%)Ni-Al_(2)O_(3) system-also through coprecipitation,followed by modifying with a magnesium-containing precursor.For the catalysts of the first series,the inclusion of magnesium into LDH lattice led to a significant increase in catalytic activity in hydrogen extraction(10HQ dehydrogenation reaction).Despite the decrease in the content of catalytically active nickel,a significant increase in the yield of the dehydrogenation product was observed.This regularity is presumably associated with appearance of basic sites,that accelerates the dehydrogenation reaction.In the case of the second series,activity of pre-reduced(600°C,H_(2))catalysts in dehydrogenation of 10HQ also significantly depends on a MgO content and is maximal at Mg:Ni weight ratio 0.056.Using an in-depth study of structure of the original and reduced catalyst samples(Ni-Al_(2)O_(3) and Ni-MgNiOx-Al_(2)O_(3)),it was shown that this regularity is associated with the increased resistance of catalytically active Ni particles to agglomeration during the reductive activation.Also,using the Ni-MgNiOx-Al_(2)O_(3)catalyst for hydrogen storage process(hydrogenation reaction),the possibility of deep quinoline hydrogenation(up to 10HQ)in a flow-type reactor was demonstrated for the first time.

Integration of morphology and electronic structure modulation on cobalt phosphide nanosheets to boost photocatalytic hydrogen evolution from ammonia borane hydrolysis

The controllable and safe hydrogen storage technologies are widely recognized as the main bottleneck for the accomplishment of sustainable hydrogen energy.Ammonia borane(AB)has regarded as a competitive candidate for chemical hydrogen storage.However,developing efficient yet high-performance catalysts towards hydrogen evolution from AB hydrolysis remains an enormous challenge.Herein,cobalt phosphide nanosheets are synthesized by a facile salt-assisted along with low-temperature phosphidation strategy for simultaneously modulating its morphology and electronic structure,and function as hydrogen evolution photocatalysts.Impressively,the Co_(2)P nanosheets display extraordinary performance with a record high turnover frequency of 44.9 min^(-1),outperforming most of the noble-metal-free catalysts reported to date.This remarkable performance is attributed to its desired nanosheets structure,featuring with high specific surface area,abundant exposed active sites,and short charge diffusion paths.Our findings provide a novel strategy for regulating metal phosphides with desired phase structure and morphology for energy-related applications and beyond.

Enhanced nitrite electroreduction to ammonia via interfacial dual-site adsorption

The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving the NH_(3) selectivity is to facilitate adsorption and activation of NO_(2)^(−),which is generally undesirable in unitary species.In this work,an efficient NO_(2)^(−)RR catalyst is constructed by cooperating Pd with In2O3,in which NO_(2)^(−)could adsorb on interfacial dual-site through“Pd–N–O–In”linkage,leading to strengthened NO_(2)^(−)adsorption and easier N=O bond cleavage than that on unitary Pd or In2O3.Moreover,the Pd/In_(2)O_(3)composite exhibits moderate H^(*)adsorption,which may facilitate protonation kinetics while inhibiting competitive HER.As a result,it exhibits a fairly high NH_(3)yield rate of 622.76 mmol h^(−1)g^(−1)cat with a Faradaic efficiency(FE)of 95.72%,good selectivity of 91.96%,and cycling stability towards the NO_(2)^(−)RR,surpassing unitary In_(2)O_(3)and Pd/C electrocatalysts.Besides,computed results indicate that NH_(3)production on Pd/In_(2)O_(3)follows the deoxidation to hydrogenation pathway.This work highlights the significance of H^(*)and NO_(2)^(−)adsorption modulation and N=O activation in NO_(2)^(−)RR electrochemistry by creating synergy between a mediocre catalyst with an appropriate cooperator.

Cu-based heterojunction catalysts for electrocatalytic nitrate reduction to ammonia

Copper-based catalysts have garnered wide attention in the field of electrocatalytic nitrate reduction for ammonia production due to their low hydrogen precipitation activity and high ammonia selectivity.However,they still face challenges pertaining of poor stability and low activity,which hinder their further application.Herein,we present a Cu_(2)O/Cu heterojunction catalyst supported on nitrogen-doped porous carbon for nitrate reduction.High resolution transmission electron microscopy(HRTEM)and X-ray Diffraction(XRD)results confirm the presence of Cu_(2)O/Cu heterojunctions,which serve as an active phase in catalysis.The nitrogen-doped porous carbon as a carrier not only enhances the catalyst’s stability,but also facilitates the exposure and dispersion of active sites.At-1.29 V(vs.RHE),the maximum production rate of ammonia reaches 8.8 mg/(mg·h)with a Faradaic efficiency of 92.8%.This study also elucidates the effect of Cu_(2)O-to-Cu ratio in the heterojunction on catalytic performance,thereby providing valuable insights for designing efficient nitrate reduction catalysts for ammonia production.

Promoting electroreduction of nitrite to ammonia over electron-deficient Pd modulated by rectifying Schottky contacts

Electrochemical nitrite reduction reaction(NO_(2)^(-)RR) is a potential sustainable route for regulating the nitrogen cycle and ambient ammonia(NH_(3)) synthesis.However,it remains a challenge to precisely regulate the reaction pathways and inhibit competing reactions(e.g.hydrogenolysis) for efficient and selective NH_(3) production in an aqueous solution environment.Here,we utilize the Schottky barrier-induced surface electric field to construct high-density electron-deficient Pd nanoparticles by modulating the N content in the carbon carrier to promote the enrichment and immobilization of NO_(2)^(-)on the electrode surface,which ensures the ultimate selectivity for NH_(3).With these properties,Pd@N_(0.14)C with the highest N content achieved excellent catalytic performance for the reduction of NO_(2)^(-)to NH_(3) with the 100% Faraday efficiency at-0.5 and-0.6 V vs,reversible hydrogen electrode(RHE) for NH_(3) production,which was significantly better than Pd/C and Pd@N_(x)C samples with lower N content.This study opens new avenues for rational construction of efficient electrocatalysts for nitrite removal and NH_(3) electrosynthesis.

A reduced combustion mechanism of ammonia/diesel optimized with multi-objective genetic algorithm

For the deep understanding on combustion of ammonia/diesel,this study develops a reduced mechanism of ammonia/diesel with 227 species and 937 reactions.The sub-mechanism on ammonia/interactions of N-based and C-based species(N—C)/NOx is optimized using the Non-dominated Sorting Genetic Algorithm II(NSGA-II)with 200 generations.The optimized mechanism(named as 937b)is validated against combustion characteristics of ammonia/methane(which is used to examine the accuracy of N—C interactions)and ammonia/diesel blends.The ignition delay times(IDTs),the laminar flame speeds and most of key intermediate species during the combustion of ammonia/methane blends can be accurately simulated by 937b under a wide range of conditions.As for ammonia/diesel blends with various diesel energy fractions,reasonable predictions on the IDTs under pressures from 1.0 MPa to5.0 MPa as well as the laminar flame speeds are also achieved by 937b.In particular,with regard to the IDT simulations of ammonia/diesel blends,937b makes progress in both aspects of overall accuracy and computational efficiency,compared to a detailed ammonia/diesel mechanism.Further kinetic analysis reveals that the reaction pathway of ammonia during the combustion of ammonia/diesel blend mainly differs in the tendencies of oxygen additions to NH_2 and NH with different equivalence ratios.

Environmental concentration of ammonia nitrogen induced marked changes in proteome of clam Ruditapes philippinarum in dose-and time-dependent manner

Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes philippinarum.However,knowledge is lacking regarding the related proteins involved in the toxicological responses,which is vital to elucidate the underlying mechanism of ammonia nitrogen.In this study,clams R.philippinarum were exposed to ammonia nitrogen for 21 d at two environmentally relevant concentrations.The tandem mass tags approach(TMT)was applied to assay the differentially expressed proteins(DEPs)in clam gill tissues on the 3 rd and 21 st day.Finally,a total of 7263 proteins were identified.Bioinformatics analyses revealed that clam protein profiles changed in dose-and time dependent manner after ammonia nitrogen exposure.We inferred that the clams may face heavy challenges after ammonia exposure,such as unbalanced gender ratio,lysosomal disease,energy lack,neurological disorders,altered glutamine metabolism,increased lipid synthesis,and impaired immunity.Variation profiles of enzyme activities of glutaminase and glutamine synthase provided direct evidence to verify the related inference from proteome data.Most of the inferred toxic effects merit further study.This study identified important proteins related to ammonia nitrogen toxicity in the clam and indicated the severe stress of marine ammonia pollution on the healthy development of mollusc aquaculture.

Ba promoter effect on cobalt-catalyzed ammonia decomposition kinetics: A theoretical analysis

Ammonia decomposition is a key reaction in the context of hydrogen storage, transport, and release. This study combines density functional theory(DFT) calculations with microkinetic modeling to address the promotion mechanism of Ba species for ammonia decomposition on Co catalysts. The modified adsorption properties of Co upon the addition of metallic Ba or BaO suggest that the promoters play a role in alleviating the competitive adsorption of H. Calculating the full reaction pathway of ammonia decomposition shows that limiting the investigation to the N–N association step, as done previously, overlooks the effect of the promoter on the energy barriers of the NHxdehydrogenation steps. Challenges of modeling the ammonia decomposition reaction are addressed by understanding that the NH_(2) intermediate is stabilized on the step sites rather than the terrace sites. When the effect of H-coverage on the adsorption of NH_(3) is not considered in the microkinetic simulations, the results conflict with the experiments.However, accounting for the effect of H-coverage, as performed here, shows that BaO-doped Co has higher rates than pristine Co and Ba-doped Co at the reaction temperature of 723.15 K. When H is adsorbed on the Ba-doped Co, the adsorption of ammonia becomes significantly endergonic, which makes the rates relatively slow. The superiority of the BaO-promoted catalyst is attributed to a lower energy for the transition state of the rate-determining step, coupled with a reduced impact of the hydrogen coverage on weakening the ammonia adsorption. The kinetic analysis of the influence of Ba and BaO on the Co surface shows that BaO-doped Co aligns more closely with experimental observations than Badoped Co. This implies that Ba on the Co surface is likely to be in an oxide form under reaction conditions.Understanding the kinetics of the ammonia decomposition reaction provides a foundation for developing highly effective catalysts to accelerate the industrial utilization of ammonia as a sustainable hydrogen carrier.

Solar hydrogen production from electrochemical ammonia splitting powered by a single perovskite solar cell

For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize 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 N_(2) and H_(2) 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.

Comprehensive kinetic study on ammonia/ethylene counter-flow diffusion flames:influences of diluents

This study aimed to investigate the effects of ammonia addition on ethylene counter-flow diffusion flames with different diluents on the fuel or oxidizer side,using kinetic analyses.A special emphasis was put on assessing the coupled chemical effects of NH_(3) and CO_(2) on C2H4 combustion chemistry.The chemical effects could be evaluated by comparing fictitious inert NH_(3) or CO_(2) with normal active NH_(3) or CO_(2).The results revealed that the addition of NH_(3) decreased the mole fractions and production rates of key soot precursors,such as acetylene,propynyl,and benzene.When CO_(2) was used as the dilution gas,the coupled chemical effects of NH_(3) and CO_(2) were affected by the chemical effects of CO_(2) to varying degrees.With the oxidizer-side CO_(2) addition,the coupled chemical effects of NH_(3) and CO_(2) reduced the mole fractions of H,O,OH radicals,acetylene,propynyl,and benzene,while the effects differed from the fuel-side CO_(2) addition.The coupled chemical effects of NH_(3) and CO_(2) also promoted the formation of aldehyde contaminants,such as acetaldehyde,to some extent,particularly with CO_(2) addition on the oxidizer side.

Insights into Ru Crystal Phase Regulated by Reducing Agent for the Catalytic Activity of Ammonia Synthesis

Ru nanoparticles with fcc and hcp crystal phases were obtained by chemical reduction method using different precursors and reducing agents,and their catalytic properties in ammonia synthesis were compared.The catalytic reaction rate(666.4μmol·h^(−1)·g^(−1))of fcc Ru catalyst is higher than that of hcp Ru(378.9μmol·h^(−1)·g^(−1))at the reaction temperature(400℃)and pressure(1 MPa).The results indicate that the exposed crystal faces have a certain impact on the catalytic activity.The dissociation ability to N_(2) of fcc Ru exposed(111)and(200)is better than that of hcp Ru exposed(100).When the ruthenium catalyst was loaded on rod-like CeO_(2) support,the ammonia synthesis activity was further improved.The ammonia synthesis activity of fcc Ru/CeO_(2) is 1.4 times higher than that of hcp Ru/CeO_(2) under the test conditions.

Exploring nitrogen reduction reaction mechanisms in electrocatalytic ammonia synthesis:A comprehensive review

The electrochemical nitrogen reduction reaction(eNRR)holds significant promise as a sustainable alternative to the conventional large-scale Haber Bosch process,offering a carbon footprint-free approach for ammonia synthesis.While the process is thermodynamically feasible at ambient temperature and pressure,challenges such as the competing hydrogen evolution reaction,low nitrogen solubility in electrolytes,and the activation of inert dinitrogen(N_(2))gas adversely affect the performance of ammonia production.These hurdles result in low Faradaic efficiency and low ammonia production rate,which pose obstacles to the commercialisation of the process.Researchers have been actively designing and proposing various electrocatalysts to address these issues,but challenges still need to be resolved.A key strategy in electrocatalyst design lies in understanding the underlying mechanisms that govern the success or failure of the electrocatalyst in driving the electrochemical reaction.Through mechanistic studies,we gain valuable insights into the factors affecting the reaction,enabling us to propose optimised designs to overcome the barriers.This review aims to provide a comprehensive understanding of the various mechanisms involved in eNRR on the electrocatalyst surface.It delves into the various mechanisms such as dissociative,associative,Mars-van Krevelen,lithium-mediated nitrogen reduction and surface hydrogenation mechanisms of nitrogen reduction.By unravelling the intricacies of eNRR mechanisms and exploring promising avenues,we can pave the way for more efficient and commercially viable ammonia synthesis through this sustainable electrochemical process by designing an efficient electrocatalyst.

100 W-class green hydrogen production from ammonia at a dual-layer electrode containing a Pt-Ir catalyst for an alkaline electrolytic process

Ammonia allows storage and transport of hydrogen over long distances and is an attractive potential hydrogen carrier.Electrochemical decomposition has recently been used for the conversion of ammonia to hydrogen and is regarded as a future technology for production of CO_(2)-free pure hydrogen.Herein,a heterostructural Pt-Ir dual-layer electrode is developed and shown to achieve successful long-term operation in an ammonia electrolyzer with an anion exchange membrane(AEM).This electrolyzer consisted of eight membra ne electrode assemblies(MEAs)with a total geometric area of 200 cm~2 on the anode side,which resulted in a hydrogen production rate of 25 L h~(-1).We observed the degradation in MEA performance attributed to changes in the anode catalyst layer during hydrogen production via ammonia electrolysis.Furthermore,we demonstrated the relationship between the ammonia oxidation reaction(AOR)and the oxygen evolution reaction(OER).

Comprehensive understanding of the thriving electrocatalytic nitrate/nitrite reduction to ammonia under ambient conditions

Ammonia(NH_(3))is a multifunctional compound that is an important feedstock for the agricultural and pharmaceutical industries and attractive energy storage medium.At present,NH_(3)synthesis is highly dependent on the conventional Haber–Bosch process that operates under harsh conditions,which consumes large quantities of fossil fuels and releases a large amount of carbon dioxide.As an alternative,electrosynthesis is a prospective method for producing NH_(3)under normal temperature and pressure conditions.Although electrocatalytic nitrogen reduction to ammonia has attracted considerable attentions,the low solubility of N_(2)and high N≡N cracking energy render the achievements of high NH_(3) yield rate and Faradaic efficiency difficult.Nitrate and nitrite(NO_(x)^(-))are common N-containing pollutants.Due to their high solubilities and low dissociation energy of N=O,NO_(x)^(-)−are ideal raw materials for NH_(3) production.Therefore,electrocatalytic NO_(x)^(-)−reduction to NH_(3)(eNO_(x)RR)is a prospective strategy to simultaneously realise environmental protection and NH_(3) synthesis.This review offers a comprehensive understanding of the thriving eNO_(x)RR under ambient conditions.At first,the popular theory and mechanism of eNO_(x)RR and a summary of the measurement system and evaluation criteria are introduced.Thereafter,various strategies for developing NO_(x)−reduction catalysts are systematically presented and discussed.Finally,the challenges and possible prospects of electrocatalytic NO_(x)^(-1) reduction are outlined to facilitate energy-saving and environmentally friendly large-scale synthesis of NH_(3) in the future.

Dielectric barrier discharge plasma-assisted catalytic ammonia synthesis:synergistic effect of Ni-MOF-74 catalyst and nanosecond pulsed plasma

Ammonia is one of the most important chemical raw materials in both manufacture and life of human.Traditionally Haber-Bosch method for ammonia synthesis involves high temperature and high pressure conditions,leading to significant energy consumption and environmental pollution.Non-thermal plasma(NTP) is a promising alternative approach to ammonia synthesis at low temperature and atmospheric pressure.In this study,the synergistic effect of nanosecond pulsed dielectric barrier discharge(np-DBD) and Ni-MOF-74 catalyst was investigated in ammonia synthesis by utilizing nitrogen and hydrogen as feedstock.The results demonstrated that the plasma catalytic-synthesis process parameters play a crucial role in the synthesis process of ammonia.The highest ammonia synthesis rate of 5145.16 μmol·g^(-1)·h^(-1)with an energy efficiency of 1.27 g·kWh^(-1)was observed in the presence of the Ni-MOF-74 catalyst,which was3.7 times higher than that without Ni-MOF-74 catalyst.The synergistic effect of Ni-MOF-74catalyst and nanosecond pulsed plasma was explored by in-situ plasma discharge diagnostics.

Sustainable ammonia synthesis:An in-depth review of non-thermal plasma technologies

Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free combustion.Additionally,it offers convenient transportation and storage as a hydrogen carrier.The dominant method used for large-scale ammonia production is the Haber-Bosch process,which requires high temperatures and pressures and is energy-intensive.However,non-thermal plasma offers an eco-friendly alternative for ammonia synthesis,gaining significant attention.It enables ammonia production at lower temperatures and pressures using plasma technology.This review provides insights into the catalyst and reactor developments,which are pivotal for promoting ammonia efficiency and addressing existing challenges.At first,the reaction kinetics and mechanisms are introduced to gain a comprehensive understanding of the reaction pathways involved in plasma-assisted ammonia synthesis.Thereafter,the enhancement of ammonia synthesis efficiency is discussed by developing and optimizing plasma reactors and effective catalysts.The effect of other feeding sources,such as water and methane,instead of hydrogen is also presented.Finally,the challenges and possible solutions are outlined to facilitate energy-saving and enhance ammonia efficiency in the future.

Low-temperature chemistry in plasma-driven ammonia oxidative pyrolysis

Ammonia is gaining increasing attention as a green alternative fuel for achieving large-scale carbon emission reduction. Despite its potential technical prospects, the harsh ignition conditions and slow flame propagation speed of ammonia pose significant challenges to its application in engines. Non-equilibrium plasma has been identified as a promising method, but current research on plasma-enhanced ammonia combustion is limited and primarily focuses on ignition characteristics revealed by kinetic models. In this study, low-temperature and low-pressure chemistry in plasma-assisted ammonia oxidative pyrolysis is investigated by integrated studies of steady-state GC measurements and mathematical simulation. The detailed kinetic mechanism of NH_(3) decomposition in plasma-driven Ar/NH_(3) and Ar/NH_(3)/O_(2) mixtures has been developed. The numerical model has good agreements with the experimental measurements in NH_(3)/O_(2) consumption and N_(2)/H_(2) generation, which demonstrates the rationality of modelling. Based on the modelling results, species density profiles, path flux and sensitivity analysis for the key plasmaproduced species such as NH_(2), NH, H_(2), OH, H, O, O(^(1)D), O_(2)(a^(1)△_(g)), O_(2)(b^(1)∑_(g)^(+)), Ar^(*), H^(-), Ar^(+), NH_(3)^(+), O_(2)^(-) in the discharge and afterglow are analyzed in detail to illustrate the effectiveness of the active species on NH_(3) excitation and decomposition at low temperature and relatively higher E/N values. The results revealed that NH_(2), NH, H as well as H_(2) are primarily generated through the electron collision reactions e + NH_(3)→ e + NH_(2)+ H, e + NH_(3)→ e + NH + H_(2) and the excited-argon collision reaction Ar^(*) + NH_(3)+ H → Ar + NH_(2)+ 2H, which will then react with highly reactive oxidative species such as O_(2)^(*), O^(*), O, OH, and O_(2) to produce stable products of NOx and H_(2)O. NH_(3)→ NH is found a specific pathway for NH_(3) consumption with plasma assistance, which further highlights the enhanced kinetic effects.

Rare Earth Elements(La,Ce,Pr)Modified Co/NC Catalyst for Efficient and Stable Ammonia Decomposition to Hydrogen Production

Co/NC catalysts modified with rare earth elements(La,Ce,Pr)were prepared by pyrolysis of rare earth elements doped ZIF-67.The experimental results show that the modification of rare earth elements significantly improves the ammonia decomposition activity and stability of the Co/NC catalyst.The La-Co/NC catalyst can achieve an 82.3%ammonia decomposition and 18.4 mmol hydrogen production rate at 550℃with a GHSV of 20000 cm^(3)·h^(-1).Furthermore,no obvious performance degradation is observed after 72 hours of reaction for all rare earth elements modified catalysts.It is shown that the modification of rare earth elements significantly improves the surface alkalinity and surface chemical state of the catalyst,and thus improves the ammonia decomposition activity of the catalyst.A new type of high-performance ammonia decomposition Co-based catalyst is proposed,and the promoting effect of rare earth elements on the activity of ammonia decomposition is revealed.

Removal of ammonia nitrogen from inorganic wastewater by AgBr/C_(3)N_(5)heterojunction under visible light irradiation

AgBr/C_(3)N_(5)composite was prepared by in-situ precipitation of AgBr on the surface of nitrogen-rich carbon nitride(C_(3)N_(5)).The crystal phase,chemical composition,elemental composition,spectral absorption and photoelectron-hole separation of the composite were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectroscopy(UV-vis DRS)and photoluminescence spectroscopy(PL).The construction of AgBr and C_(3)N_(5)heterojunction could broaden the spectral response range,realize the efficient separation of photoelectrons and holes,and thus improve the photocatalytic performance.The photocatalytic performance of the composite material was studied by simulating inorganic ammonia nitrogen wastewater with NH_(4)Cl solution.The dosage of the composite material was 0.10 g,the initial mass concentration of NH_(4)Cl solution was 100 mg/L,and the initial pH was 10.0.The removal rate of ammonia nitrogen by the composite material reached 90.27%after 60 min of simulated visible light irradiation.After 5 cycles,the removal rate of ammonia nitrogen only declined by 0.12%.The composite material showed good photocatalytic performance and stability.The Z-scheme mechanism effectively retained the reduction and oxidation activities of photoelectrons and holes,which could change O_(2)and H2O to active groups such as superoxide radicals(·O_(2)-)and hydroxyl radicals(·OH),respectively,achieving efficient removal of inorganic ammonia nitrogen.

In Situ-Constructed Li_(x)MoS_(2)with Highly Exposed Interface Boosting High-Loading and Long-Life Cathode for All-Solid-State Li-S Batteries

As the persistent concerns regarding sluggish reaction kinetics and insufficient conductivities of sulfur cathodes in all-solid-state Li-S batteries(ASSLSBs),numerous carbon additives and solid-state electrolytes(SSEs)have been incorporated into the cathode to facilitate ion/electron pathways around sulfur.However,this has resulted in a reduced capacity and decomposition of SSEs.Therefore,it is worth exploring neotype sulfur hosts with electronic/ionic conductivity in the cathode.Herein,we present a hybrid cathode composed of few-layered S/MoS_(2)/C nanosheets(<5 layers)that exhibits high-loading and long-life performance without the need of additional carbon additives in advanced ASSLSBs.The multifunctional MoS_(2)/C host exposes the abundant surface for intimate contacting sites,in situ-formed LixMoS_(2)during discharging as mixed ion/electron conductive network improves the S/Li2S conversion,and contributes extra capacity for the part of active materials.With a high active material content(S+MoS_(2)/C)of 60 wt%in the S/MoS_(2)/C/Li_(6)PS_(5)Cl cathode composite(the carbon content is only~3.97 wt%),the S/MoS_(2)/C electrode delivers excellent electrochemical performance,with a high reversible discharge capacity of 980.3 mAh g^(-1)(588.2 mAh g^(-1)based on the whole cathode weight)after 100 cycles at 100 mA g^(-1).The stable cycling performance is observed over 3500 cycles with a Coulombic efficiency of 98.5%at 600 mA g^(-1),while a high areal capacity of 10.4 mAh cm^(-2)is achieved with active material loading of 12.8 mg cm^(-2).