Acid Leaching Method Research Articles

A sustainable process for selective recovery of metals from gallium-bearing waste generated from LED industry

With the rapid development of the LED industry, gallium (Ga)-bearing waste generated is regarded as one of the most hazardous as it typically contains heavy metals and combustible organics. Traditional technologies are characterized by long processing routes, complex metal separation processes and significant secondary pollution emission. In this study, we proposed an innovative and green strategy to selectively recovery Ga from Ga-bearing waste by using a quantitative phase-controlling transition process. In the phase-controlling transition process, the gallium nitride (GaN) and indium (In) are converted to alkali-soluble gallium (III) oxide (Ga2O3) and alkali-insoluble indium oxides (In2O3) by oxidation calcination, while nitrogen is converted into diatomic nitrogen gas instead of ammonia/ammonium (NH3/NH4+). By selective leaching with NaOH solution, nearly 92.65% of Ga can be recycled with a leaching selectivity of 99.3%, while little emissions of NH3/NH4+. Ga2O3 with a purity of 99.97% was obtained from the leachate which is also economy promising by economic assessment. Therefore, the proposed methodology compared to the conventional acid and alkali leaching methods is potentially greener and more efficient process for extracting valuable metals from nitrogen-bearing solid waste.

Comparative study on removal of metallurgical silicon impurities by different acid leaching methods

Hydrometallurgy is considered a promising method to produce solar-grade silicon (SOG-Si) from metallurgical-grade silicon (MG-Si) due to its advantages of low cost, simple operation, and easy control. In this paper, the effects of particle size of MG-Si, type of acid, leaching time, temperature, and liquid-to-solid ratio on the purification efficiency were investigated in an external field environment with the addition of ultrasound. The purification efficiencies of the two acid-leaching methods were compared. It was found that the simultaneous use of HCl + HNO3 was more effective than using only HCl for impurity removal in MG-Si: the extraction efficiencies of impurities Fe and Al were increased by 2.2% and 13.4%, respectively. The impurity contents in MG-Si before and after calcination pretreatment were also compared. This paper is expected to help researchers select the appropriate hydrometallurgical technique to reduce the impurity content in MG-Si.

Kaolinite clay as a raw material for erbium extraction

Currently, due to the high rate of development of the rare-earth industry, new sources of raw materials are being mastered and new technologies for obtaining rare-earth metals (REM) are being developed. Studies have shown that REM in kaolinite clays of Alexeevskoe deposit in Kazakhstan and Egypt deposits in Sinai Peninsula (K-Watt, K-Tech) and in Aswan region (KB,KPL) are mainly represented by erbium (Er). Production of Er concentrate is considered as a by-product in a comprehensive middlings processing of kaolinite clays to produce alumina and building materials. The possibility of obtaining Er concentrate by sulfuric acid leaching and sorption concentration methods has been determined. Optimal technological conditions of kaolinite clays leaching is the use of 5% solution of H2SO4, at temperature 50 °C, duration 60 min and L:S ratio = 5. Under these conditions the separation of REM from the main components Fe2O3, Al2O3, SiO2 is achieved. Concentrates were obtained with the content of the sum of REM oxides from 91.3 to 93.4%, in which the relative content of Er was from 64.89 to 90.82%. The results showed that the developed technology can be used for processing of erbium-containing kaolinite clays of various deposits.

The study of acid leaching and electrodeposition method to enhance Pb recovery from galena concentrate

Galena is a potential source of lead (Pb), which has many used for lead batteries. Indonesia is a country with potential sources of galena mineral. This investigation showed Pb extraction of 0.274 % using acetic acid leaching method with 1.0 M acetic acid at 50oC from galena concentrate. This study showed remarkable enhancement of Pb extraction until 8.96 % applying electrodeposition method using 1.0 M acetic acid at 50oC. Varied acetic acid concentrations were applied for 1.0 M, 3.0 M, 5.0 M, and 7.0 M and varied temperatures were applied in this study for 50 °C, 65 °C, and 80 °C. The percentage of Pb extraction showed a consistency with the reduction of % Pb extraction with increasing acid concentrations and increasing temperatures. This findings is assumed to be related to exothermic PbS dissolution shifted to decreasing Pb(II) ion concentration and ion pair formation retarding Pb dissolution. The percentage of Pb from leaching process was determined by AAS (Atomic Absorption Spectrophotometer), while the percentage of Pb by electrodeposition method was determined from quantity of Pb deposit on cathode of an electrochemical cell. This investigation shows a significant breakthrough for enhancement of Pb recovery from galena mineral.

Development of ceramic grade red iron oxide pigment from waste iron source

Ceramic grade red iron oxide (α-Fe2O3) nanoparticles pigments have been synthesized from waste condensed milk containers which contain a prominent amount of iron (93.2%). The synthesis method comprised of two steps: in the first step ferrous sulfate was prepared following an acid leaching method; while the second step was oxidation and calcination of ferrous sulfate to produce desired α-Fe2O3 in nano form. The structure, functional groups, chemical state, morphology, particle size, surface area, elemental, thermal analysis and magnetic properties of the samples were investigated using XRD, FTIR, XPS, SEM, BET, EDS, TG-DT and VSM respectively. Pure hematite (α-Fe2O3) phase was confirmed by XRD and the average crystal sizes were in the range 34–126 nm have been performed by Debye-Scherer's formula, which are consistent with the results as achieved from SEM images. Agglomerated irregular spherical nanoparticles (45–149 nm) were found in SEM image. The surface chemistry and the chemical state (Fe3+) of the hematite nanoparticles was also confirmed by XPS. The mesoporous nature of the nanoparticles with high surface area were measured by BET and it has been revealed that the BET specific surface area (33.55 m2/g) was marginally higher than the commercial one. The magnetic nature of the nanoparticles was portrayed by VSM and the nanoparticles showed the ferromagnetic behavior. Moreover, particle size distributions and zeta potential values have been also measured by DLS.

Effect of graphene on self-healing performance of hydroxyapatite/polydimethysiloxane composites

ABSTRACT Recently, polymeric self-healing materials are tremendously being exploited in the fields of biomedical and other advanced engineering applications. However, mechanism of the self-healing materials is not very clear and the healing performance is very poor for the existed materials. Therefore in our present investigation, hydroxyapatite (HA) bioceramic, graphene (Gr) and polydimethysiloxane (PDMS) were used to develop a high performance novel self-healing composite. Here, we proposed a single step accessible preparation of short-layers graphene by the exfoliation of graphite layers via acid leaching method. Further, Gr/HA embedded PDMS membranes were prepared using a vascular method. We prepared the PDMS elastomer (resin:hardener ratio = 1:1) being mixed with 2 wt% HA and varying concentrations 0.1 wt%, 0.3 wt%, 0.5 wt% of Gr. The band gap, phase structure, crystalline and chemical structure of the Gr/HA composite films were characterized using UV-Vis, XRD and FTIR studies. A series of tensile tests were conducted to measure virgin and healed tensile specimens. The highest mechanical property was achieved at 2 wt% of HA. But best self-healing performance of the 0.1 wt%Gr composite was obtained from the recovery of tensile properties. The healing efficiency was found to depend on the curing properties of PDMS varied with HA/Gr reinforcement and quantity of healing agent delivered.

An efficient ammonium chloride roasting approach to separating salt from the electrolytic carbon in molten carbonate

Molten salt carbon dioxide capture and electrochemical transformation (MSCC-ET) is a promising solution for reducing global CO2 emissions. However, effectively separating molten salt electrolytes from carbon material using an environmental manner remained to be solved. Typical separation methods (acid-leaching and water-leaching) will generate secondary CO2 emissions and need a high consumption of water and heat energy. Herein, we propose an ammonium chloride (NH4Cl) roasting approach (ACRA) to separate lithium salts from the carbon obtained by the MSCC-ET process. Using the NH4Cl-assisted roasting approach, the low-soluble Li2CO3 is converted to high-soluble LiCl that can be easily separated from the carbon. The recovery rate of carbon material reaches 91.67 % at optimal roasting conditions. Compared with water-leaching method, ACRA process can save 80.61 % of water and 76.79 % of heat energy. In addition, ACRA process can save 56.36 % of water and 47.78 % of heat energy comparing with acid-leaching method. All in all, this work provides a closed-loop strategy to separate and reutilize molten salt electrolytes for the MSCC-ET.

Iron-based denitration catalyst derived from Fenton sludge: Optimization analysis of selective dealkalization and influence mechanism of calcination temperature

Fenton sludge from sewage treatment plants is a kind of hazardous waste that causes serious harm to the ecological environment. In this study, the potential of preparing a novel selective catalytic reduction (SCR) denitration (deNOx) catalyst was evaluated through selective dealkalization followed by calcination using Fenton sludge. The effects of water leaching, carbon dioxide leaching, and acid leaching methods (organic and inorganic acid) on Fenton sludge dealkalization were studied, taking the total dealkalization and active component retention rates and deNOx efficiency as comprehensive considerations. Results showed that acid leaching method has the best leaching effect on free alkali and chemically combined alkali, the order of dealkalization rates was FSH2SO4 (94.23%)>FSHCl (92.18%)>FSHNO3 (89.93%)>FSCH3COOH (81.07%). Through comprehensive comparison, FSHCl exhibited the best catalytic active and excellent selective dealkalization performance, achieving relatively high total dealkalization rate while retaining the active components to the greatest extent (86.73%). On this basis, the effects of calcination temperature on catalytic activity, as well as physical and chemical properties of the catalyst were studied. The MFS-450 catalyst exhibited the largest surface area (76.53 m2/g), pore volume (0.23 cm3/g), abundant oxygen-containing functional groups, excellent surface acidity (0.779 μmol/m2), and redox properties (5.07 mmol/g). Besides, it has the best low-temperature SCR activity and the widest reaction temperature window, with nitrogen oxide (NOx) conversion exceeding 90% at temperatures between 293 and 471 °C. This research contributes a representative example of converting Fenton sludge into valuable materials and may open a new avenue to synthesizing high-activity SCR catalyst from low-cost feedstocks.

Magnetized vermiculite loaded with waste polishing powder to recover phosphorus in waste water

In view of the phosphorus pollution in water bodies and the shortage of phosphate rock resources, the preparation of cheap, accessible and easy-to-recycle adsorbents for the recovery of phosphorus in sewage has attracted much attention. In this study, waste rare earth polishing powder (WP) was doped with magnetized vermiculite (Mev) at a mass ratio of 1:1 through acid leaching and advection precipitation method to prepare the magnetic Mev-WP composite material for adsorbing and recovering phosphorus in the water. The results show that Mev-WP is easy to be separated from water by an external magnetic field and the main reason why Mev-WP specificity can adsorb phosphorus is that the rare earth elements of La and Ce in the polishing powder are loaded on the flake magnetized vermiculite in the form of La (OH)3 and Ce(OH)3. The phosphorus adsorption process of Mev-WP is an endothermic mono-layer chemical adsorption that includes boundary layer diffusion and internal diffusion, of which the boundary layer diffusion is the rate-limiting step, which can complete rapid adsorption within 30 min. Except for HCO3− ions, other coexisting anions in the water have no significant effect on adsorption, but the adsorption capacity is greatly affected by pH. At pH 11 to 3, the material is a stable and environmentally-friendly adsorbent, and with the decrease of pH, the adsorption capacity increases significantly. When the pH is 3, at 25 °C, the adsorption capacity can reach up to 63.79 mg/g. The phosphorus adsorption mechanism of Mev-WP is electrostatic attraction and ligand exchange between -OH on La-OH and Ce-OH and phosphate groups in the water to generate La-O-P and Ce-O-P coordination complexes to remove phosphorus. After 5 times desorption and recycling, the phosphorus recovery rate of the material reaches 65 %, and the deep phosphorus removal verification in urban sewage is effective. Studies have shown that Mev-WP is a promising specific phosphorus recovery agent.

A closed-circuit cycle process for recovery of carbon and valuable components from spent carbon cathode by hydrothermal acid-leaching method.

Spent carbon cathode (SCC) as a hazardous solid waste produced in aluminum electrolysis industry, contains plenty valuable components but generate a seriously threat to the environment. This paper focus on a closed-circuit cycle process for direct treatment of SCC based on the hydrothermal acid-leaching method. Thermodynamic calculation, single factor experiment, orthogonal experiment and kinetic study are utilized to obtain the leaching properties of impurities, optimize the leaching conditions, study the influence of conditions on leaching, and capture the restriction factors of leaching. The results indicate that the carbon content of the treated SCC can reach 97.3% when the leaching condition attach the optimal (liquid-solid ratio of 25mL/g, temperature of 413K, time of 270min and acid concentration of 4mol/L), and liquid-solid ratio is regarded as the crucial factor influencing on that. In addition, the activation energy of impurities reaches 6.25kJ/mol and the whole leaching process is controlled by the diffusion extent. Finally, the filtrate after the hydrothermal acid leaching is treated, and calcium fluoride, cryolite and sodium chloride are successfully separated. The proposed process eliminates the harm of SCC to the environment, and completes a closed-circuit cycle for the treatment of SCC and recovery of valuable components. It enriches the hydrometallurgical processes of SCC, and provides an attractive scheme for the treatment of SCC.

Phosphate recovery from waste fish bones ash by acidic leaching method and iron phosphate production using electrocoagulation method

This study aims to test three different acids (HCl, H2SO4, HNO3) for phosphate (PO4−3) extraction from waste fish bones ash using response surface methodology (RSM). Moreover, PO4−3 recovery from the P-rich solution as iron(III) phosphate (FePO4) was carried out using iron-supported electrocoagulation process (EC) with a Box-Behnken Design. The results showed that nitric acid (HNO3) supplied better phosphate extraction compared to hydrochloric acid (HCl) and sulfuric acid (H2SO4). Approximately 97.5% of PO4−3 was recovered in the form of a rich PO4−3 extraction solution using 6 M HNO3 and an acid-ash ratio of 13.7 kg acid/kg ash. The maximum recovery efficiency of phosphate (100%) was achieved at pH 4.96 and current density of 5.96 V, time of 60 min in the EC process. The operating cost of the EC process was calculated as 1.63 US$/kg PO4−3. Iron phosphate obtained in different time periods under optimum conditions were characterized by X-Ray Diffraction (XRD) analysis. According to XRD results, three different iron phosphate (lipscombite, iron(III) phosphate(V), and heptairon pentaphosphate hydrogen phosphate) were obtained. The present study suggested that P recovery from waste fish bones ash using acid leaching method and production of iron phosphate using the electrocoagulation process could be considered as a cleaner production. In addition, the study presents an environmentally and sustainable method for the recovery of phosphate resources.

EFFECT OF SULFURIC ACID CONCENTRATION ON NICKEL RECOVERY FROM LATERITE ORE BY USING ATMOSPHERIC ACID LEACHING METHOD

The processing of laterite ore by pyrometallurgy requires high temperatures whereas the Atmospheric Acid Leaching (AAL) method can be performed below 100 ℃ although its nickel recovery is inconsistent. This research aims to determine the effect of sulfuric acid concentration on nickel recovery and to determine nickel recovery after extract purification by precipitation of non-nickel metals. AAL was performed with an operating temperature of 95 °C, an operating time of 5 hours, an ore-to-solvent ratio of 0.05 g/ml, a particle size of ± 200 mesh, and sulfuric acid concentration variation of 0.2–1 M. Iron precipitation was completed with a pH variation of 0.5–3.8 by the addition of ammonia. The result showed that the concentration of sulfuric acid increased nickel recovery. The nickel recovery reached 96.43% at a concentration of sulfuric acid of 1 M. Furthermore, after extract purification, nickel recovery reached 50.61%, which was achieved at an optimum pH of 3.2.

Preparation of fly ash based titanium dioxide composite photocatalysts using spent SCR catalyst carriers

Selective catalytic reduction of NOx with NH3 (NH3-SCR) is a commonly used method to remove NOx from flue gas. However, spent SCR catalysts that have been landfilled bring potential environmental hazards and an enormous waste of resources. To resolve the problem, this paper explores a method for recycling spent SCR catalysts by compositing it with fly ash to prepare a high value-added photocatalyst. Ti in the spent catalysts was extracted into TiOSO4 via the acid leaching method. Then the surface of FA was loaded via hydrolysis precipitation to form nano-TiO2-coated composite particles (Ti-FA). Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) spectra confirmed the formation of heterogeneous structures including Si-O-Ti, Fe-O-Ti. The UV degradation of 10 ppm rhodamine B was found to be consistent with that of P25 at 60 min (97.12%), confirming the reliable activity of the prepared photocatalyst. A heterostructures photocatalyst with excellent catalytic performance was successfully constructed by using spent SCR catalysts and loaded on the surface of another solid waste FA via its dispersion and the abundance of active components. The catalytic ability for rhodamine B exceeds that of P25, and the technology has broad application prospects in light of its cost advantage.

Acid Isolation Techniques for Silica isolation from Rice Husk and Determination of Its Physicochemical Properties

Previous research showed that rice husk has a high silica content so it becomes an alternative for processing rice waste. The acid leaching method is a technique to isolate silica by adding an acid solution. The research aim is to obtain the optimum silica yield and determine the chemical ash content of rice husks (rice IR-64,). Rice husks were first calcined at two various temperatures and times. The average yields obtained were 19.54% (500oC / 1 hr), 18.42% (500oC / 2 hrs), 25.03% (700oC /1 hr), and 22.4% (700oC/2 hrs). The physical appearance of ash was grains and white (700 oC/1hr), that were rinsed with 1 M HCl solution to remove impurities. Added 1 M NaOH was to form sodium silicate. The last step was to isolate silica using different concentrations of HCl and HNO3 (3 M, 2 M, and 1 M). The highest result was 99.87% of silica under HNO3 1 M solution. An infrared study supports that the isolated product was silica, with the presence of prominent peaks at 1102 cm-1 (stretching Si-O) and 471 cm-1 (bending Si-O). A unique peak at 958 cm-1 for Si-O-Ca present at the isolated silica using HCl 3 M, gives information on inosilicate type structure. X-ray diffraction analysis with QualX application showed that silica had cristobalite and wollastonite peaks, and the value of crystallinity index was about 63.91%.

Recovery of Fe, V, and Ti in modified Ti-bearing blast furnace slag

A two-stage oxidation—alkali leaching—acid leaching method was proposed to recovery Fe, V, and Ti in modified Ti-bearing blast furnace slag. The optimal experiment conditions of iron extraction were one-stage oxidation time 40 s and holding time 8 min. The recovery rate of iron was 89.93%. The optimum experiment conditions of vanadium extraction were total oxidation time of 126 s, NaOH concentration of 4.0 mol/L, leaching temperature of 95 °C, leaching time of 90 min, and the number of cycle was 4. The leaching rate of vanadium was 92.13%. The optimal experiment conditions of titanium extraction were HCl concentration of 4.5 mol/L, leaching temperature of 75 °C, and leaching time of 90 min. The TiO2 content of synthetic rutile was 98.61%.

Hydrogen production via in-line pyrolysis-reforming of organic solid waste enhanced by steel slags

Steel slag derivates prepared from waste steel slag using acid leach method, are employed to promote hydrogen production from organic solid waste by in-line pyrolysis-steam reforming of Chinese medicine residues (CMR). The optimum pyrolysis conditions are determined during the fast pyrolysis experiment of CMR (Tprolysis = 800 °C, FN2 = 200 mLSTP/min). During in-line pyrolysis-reforming of CMR with steel slag derivates, for example CaO(SS)-50 wt%LR compounds, as reforming catalyst, the hydrogen yield is profoundly increased from 7.57 mmol/gCMR (pyrolysis operation) to 11.49 mmol/gCMR, while tar yield has been reduced 30.50%. FeOx in LR remarkably increases lattice oxygen and adsorption oxygen in NCA-LR or NCA-LR-CaO(SS) compounds, so tar and CO conversion are efficiently improved while coke deposition on catalyst surface is significantly reduced. LR is demonstrated to be able to act as or partially alternate nickel-based catalyst during steam reforming of pyrolysis gas, which would greatly reduce the cost of hydrogen production from OSWs.

Tunnel manganese oxides prepared using recovered LiMn2O4 from spent lithium-ion batteries: Co adsorption behavior and mechanism

The purpose of this study was to investigate Cobalt (Co) removal from wastewater using synthesized manganese oxides from the recovered LiMn2O4. An efficient ultrasonication leaching method was utilized to recycle LiMn2O4 from spent lithium-ion batteries (LIBs). The recovered LiMn2O4 was used to synthesize tunnel λ-MnO2, γ-MnO2 and β-MnO2 by acid leaching and hydrothermal methods. Meanwhile, Li+ in the supernatant was recycled by the precipitation of Li3PO4. Subsequently, for the synthesized tunnel MnO2, various characterizations and sodium hydroxide titration in NaNO3 solution were performed. The effect of sorption studies presented the uptake of Co increased with the pH increasing from pH ~1 to pH ~8 and the isothermal sorption at pH ~6 showed that γ-MnO2 possessed the highest uptake amount 0.44 meq/g, and the highest distribution coefficient 2.5 × 105 mL/g. Moreover, γ-MnO2 was found without Mn3+/Mn2+ leached during the sorption process. The ion exchange-surface complexation model was adopted to study the titration, effect of pH and isotherm sorption on the ion exchange reaction mechanism of Co adsorption. Overall, this work provides an economically feasible and environmentally friendly method to recycle the spent LIBs and the γ-MnO2 synthesized from the recovered LiMn2O4 was proved to be promising adsorbents for Co removal.

Effect of the occurrence state of magnesium in talc on the adsorption of Pb(II)

It is of great significance in the resource utilization to make full use of the magnesium in the low-grade mineral to prepare new adsorption materials. In this paper, a Mg(OH)2/talc nanocomposite was prepared by migrating part of Mg2+ from the talc internal structure to the outer surface through a facile acid leaching, coprecipitation and hydrothermal method. The maximum adsorption capacity of Mg(OH)2/talc was 483.33 mg/g, which was significantly improved compared with that of Acid-activated Talc (4.79 mg/g) and pristine talc (259.17 mg/g). The main adsorption mechanism of Mg(OH)2/talc for Pb(II) ions involved electrostatic attraction and ion exchange. Adsorption and desorption cycle experiment showed that, although Mg(OH)2/talc provides a large adsorption capacity for the first time, but the second adsorption capacity decreased by 42%, the third to the fifth kept stable adsorption capacity. This results indicated that the surface of magnesium hydroxide was not stable, only used it once. While magnesium hydroxyl in talc was stable, it could provide stable cycle performance. This work can provide reference for efficient utilization of clay minerals and design novel cost-efficient adsorbents.

Utilization of Spent Nickel Catalyst as Raw Material for Ni-Rich Cathode Material

Spent nickel catalyst will be harmful to the environment if it is not processed or used properly. In fact, this waste still has a high nickel content. The treatment of spent nickel catalysts has been widely reported, but limited to nickel extraction. Since the lithium-ion batteries demand is continued to increase, then nickel is the most sought-after metal. Consequently, nickel from spent nickel catalysts could be developed as secondary source for lithium-ion battery cathode. This study aims to utilize spent nickel catalysts into more valuable materials. Nickel that has been extracted and mixed with Mn and Co has been used as raw material for nickel-rich cathode, namely NMC. Nickel extraction and NMC synthesis were using the acid leaching method followed by co-precipitation[WI1] [SSN2] . Based on the functional test performed in this work, nickel from spent nickel catalyst can be applied to Li-ion batteries. The sintering temperature that gives good characteristics and electrochemistry was found 820oC. The galvanostatic charge-discharge test gave specific capacity results for NMC of 110.4 mAh/g. The cycle test showed that NMC synthesized from spent nickel catalyst can be carried out up to 50 cycles with a capacity retention of 87.18%.

Facile Synthesis of Porous Hollow Cobalt‐Doped λ‐MnO2 Nano Architectures as a High‐performance Anode Material for Li‐ion Batteries and Li‐ion Hybrid Supercapacitors

AbstractThe cost‐effectiveness and easy availability of MnO2 have attracted researchers′ attention as an anode electrode for LIBs over other transition metal oxides. However, MnO2 usage has been limited to its low reaction reversibility and poor conversion kinetics. Besides, Li‐ion hybrid supercapacitors (LiHSCs) are in urgent demand which offers higher power densities than LIBs without compromising energy density. Among different polymorphs of MnO2, λ‐MnO2, due to its 3D spinel structure, can be applied in many applications. Usually, λ‐MnO2 can be obtained by extracting lithium from LiMn2O4 using complex electrochemical or acid leaching methods. This study presents a modified Li2O2 assisted method to obtain cobalt‐doped 3D architectures of λ‐MnO2 porous hollow nanostructures. The resultant MnxCo1‐xOy hollow structures with 5 % cobalt addition are used as anode for LIBs exhibited excellent charge reversibility and cycle stability over thousands of reaction cycles. This result is known to be one of the finest among MnO2 anodes reported to date. Also, a LiHSC device is fabricated with MnxCo1‐xOy hollow structures as anode and the device exhibits an excellent comprehensive electrochemical performance in terms of high operating voltage (4.2 V), with a specific cell capacity of 33 mAh g−1 at a high current density of 5 A g−1 and achieved the maximum power density of 12261 W kg−1 (with energy density at 81.7 Wh kg−1) with long cycle life.