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The unique S-scheme heterojunction of a 2D/2D BiVO4/metalloporphyrin (ZnTCPP) layered composite showed excellent visible-light photocatalytic N2 oxidation activity.

In recent years, Co, N co-doped carbon (Co–N–C) materials as oxygen reduction reaction (ORR) catalysts have attracted great attention because of their good ORR stability as well as decent activity. Co-doped zeolitic imidazolate framework-8 (Co@ZIF-8) as the precursor for synthesizing Co–N–C has attracted great interest recently. Co@ZIF-8 synthesis method may affect the properties of the as-synthesized Co@ZIF-8 precursors, which will surely affect the properties and ORR performance of Co@ZIF-8-derived Co–N–C catalysts. Herein, three methods, viz. room-temperature stirring method, reflux method, and hydrothermal method, were used to synthesize Co@ZIF-8 precursors. Physical characterization shows that the synthesis method has a great influence on the textural properties, composition, and graphitization degree of the as-synthesized Co–N–C catalysts. Electrochemical characterization shows that Co–N–C-R synthesized with reflux method exhibits an onset potential (Eonset) of 0.905 V, a half-wave potential (E1/2) of 0.792 V and a limiting current density (JL) of 5.85 mA cm−2 in acidic media, which are higher than those of Co–N–C–S (Eonset = 0.870 V, E1/2 = 0.770 V, JL = 4.71 mA cm−2) and Co–N–C–H (Eonset = 0.892 V, E1/2 = 0.785 V, JL = 4.68 mA cm−2) synthesized with room-temperature stirring method and hydrothermal method, respectively. The better ORR activity observed on Co–N–C-R can be attributed to its larger graphitization degree and larger mesopore volume. Catalytic stability test shows that Co–N–C-R has negligible activity loss after 5000 potential cycles. This work demonstrates that reflux method is a more suitable method for synthesizing Co–N–C catalysts for ORR.

Polyphenol compounds are widely found in natural plants and they are attracting a lot of interests in their functional activities including anti-cancer, anti-inflammatory, liver-protection, anti-bacteria, neuroprotection, anti-obesity, and other related effects. However, the mechanisms of polyphenolic functional activities are still limited. Although chemical reagent methods have been widely used to study various polyphenol activities, it is difficult to deeply investigate the specific mechanism of polyphenol activities in vivo only by chemical methods. Recently, as a method to discover biomarkers associated with polyphenol activities, foodomics technique including proteomics, metabolomics, genomics, transcriptomics and lipidomics technique was developed to study the mechanisms. In this review, we summarized the worldwide research advances of polyphenolic functional activities using foodomics techniques.

Black soldier fly larvae with high contents of lipids can be used as a novel biomass feed-stock. An efficient approach involving surfactants assisted extraction of lipid from the wet biomass in this study. Surfactants with functional molecular structure were found to be helpful to extract lipids in the extraction process. Control experiments were performed to investigate the influence of different factors (surfactant types, surfactant concentration, salt concentration, and extraction temperature) on the lipid extraction process from the wet energy biomass. These results suggested that the extraction capacity of lipid was 78.99% at the defined condition (solvent:water = 50 mL:30 mL, biomass:solvent = 30 g:50 mL, surfactant concentration = 0.5%, extraction time = 60 s, extraction temperature = 60 °C). In addition, the purities of saponifiable lipids for these surfactants used were more than 80% in the present work. Surfactant treatment had a weak effect on lipids compositions. The kinetic model of the surfactants assisted lipid extraction process was proposed. During solvent extraction, the extraction process is divided to the two main processes: washing process and diffusion process. The rate constants were 4.17 × 10−2 to 5.94 × 10−2 in the first stage and 1.43 × 10−3 to 2.78 × 10−3 in the second stage for surfactants treatment, respectively. The second stage constitutes the limitation step in the extraction process. Further, the results of thermodynamic parameters were determined from thermodynamic study of lipid extraction process. This research showed the surfactant assisted route is a high efficiency technique.

Porous liquids, a new porous material with fluidity, can be applied in numerous fields, such as gas storage and/or separation. In this work, the separation of binary gas mixtures CO2/N2 and CO2/CH4 with porous liquids was examined by molecular dynamics (MD) simulations. The pure gas adsorption capacity was analyzed with different concentrations of porous liquids. The dependence of the separation effect of a gas mixture on the total pressure and temperature was investigated. Meanwhile, for both CO2/N2 and CO2/CH4 systems, the adsorption and separation effects of porous liquids with a cage:solvent ratio of 1:12 are better than those of 1:91 and 1:170. The results of the spatial distribution function and/or trajectories indicated that porous liquids prefer CO2, leading to the location of CO2 in the channels formed in porous liquids. However, N2 and CH4 are hardly adsorbed into the bulk. The diffusion of gas molecules follows the order of CO2 > N2 (for CO2/N2) and CH4 > CO2 (for CO2/CH4) in the bulk and N2 > CO2 (for CO2/N2) and CH4 > CO2 (for CO2/CH4) at the interface of porous liquids. Upon increasing the concentrations of porous liquids, the working capacities of CO2 show small decreases in CO2/N2 and CO2/CH4 systems, but the sorbent selection parameters are higher in pressure- and temperature-swing adsorption processes. The porous liquid with a cage:solvent ratio of 1:12 is more suitable for the separation of CO2/N2 and CO2/CH4 systems than ratios of 1:91 and 1:170.

Fe/N/C full of ultrafine Fe-based species and pores is synthesized by pyrolyzing a g-C3N4-coordinated Fe matrix embedded in carbon for oxygen reduction. Enhanced oxygen reduction activity is observed on Fe/N/C with higher pore volume and the Fe/N/C catalyst with the largest pore volume shows the highest half-wave potential of 0.890 V.

Herein, by screening 89 porous materials (metal–organic frameworks and covalent organic frameworks), the ultradeep desulfurization from model gasolines was investigated by the facile adsorptive app...

The scarcity and poor long-term stability of Pt has greatly hindered its commercial application as oxygen reduction reaction (ORR) catalyst. In this work, carbon-supported Pd9Au1 alloy particles with a Pd/Au molar ratio of 9:1 synthesized by using an ethylene glycol-based reduction method were used to catalyze ethanol oxidation to coat Pd9Au1 core with Pt atomic layers to synthesize Pd9Au1@Pt/C catalyst. Physical characterization shows that the as-synthesized Pd9Au1@Pt/C catalysts present a well-defined core-shell structure and the surface Pt layers can be well controlled by tuning the amount of Pt precursor added during synthesis. Electrochemical characterization shows that among the synthesized catalysts Pd9Au1@Pt2/C with 2 atomic Pt layers exhibits the best activity and excellent stability for ORR, as evidenced by its even increased half-wave potential after 10000 potential cycles between 0.6 and 1 V in O2-saturated 0.1 M HClO4 solution. This enhanced ORR activity and stability of Pd9Au1@Pt2/C catalyst can be attributed to the compressive strain and stabilizing effect of Pd9Au1 core on Pt shell.

NH3 decomposition over non-noble catalyst to generate COx-free H2 has attracted great attention in recent years. In this work, fumed SiO2-supported Ni, Co and Ni–Co bimetallic catalysts are synthesized by using a co-impregnation method and evaluated for NH3 decomposition, which shows that the bimetallic catalysts exhibit better catalytic activity than the monometallic ones. This enhanced activity observed on bimetallic catalyst can be largely attributed to the more appropriate catalyst metal-N binding energy resulting from the synergistic effect between Ni and Co in the formed Ni–Co alloy. Among the synthesized catalysts, Ni5Co5/SiO2 synthesized with the Ni/Co molar ratio of 5:5 achieves 76.8% NH3 conversion under a GHSV of 30,000 mL h−1 g−1cat at 550 °C and shows the best catalytic activity, which can be further improved by doping with K (78.1% NH3 conversion at 30,000 mL h−1 g−1cat), and the obtained Ni5Co5/SiO2–K also shows excellent catalytic stability.

The insect lipids were recovered using one-pot manner via a high speed homogeniser from the wet black soldier fly larvae as the novelty lipid feedstocks at room temperature and pressure in this study. The comparison of the influences of different conditions (solvent types, solute-solvent ratios, water contents, and homogenization intensities) on the lipid extraction efficiency and lipid compositions were studied and evaluated. The results indicated that all the binary solvents tested in this work present a higher extraction capacity (70–74%) than the monophasic solvent increasing two-fold the lipid extraction yield. There was a significant difference between the 30.96% and 86.67% in saponifiable lipids purity for different extraction solvent systems. The effects of water contents on the lipid extraction process for relatively low contents of non-polar solvent in the binary extraction solvents system were greater than that of high contents of non-polar solvent. However, fatty acid methyl esters profiles from the energy biomass indicate that relevant fatty acids were present in all solvent extracts, with no significant variation in the FAME composition provided for different investigated conditions. Key characteristics of the recovered lipids indicate that the pretreatment process-cell disruption was a critical step in the recovery of intracellular lipids from the wet biomass, which significantly enhancing the lipid extraction process. In combination with SEM images of the damaged cells, the precise mechanism of cell disruption via the high speed homogeniser was comprehensively described. At last, the kinetic model (r2 ≥ 0.9937) of lipid extraction from the ruptured cell at various homogenization intensities (6000–14000 rpm) was explored in preliminary. The extraction constants were determined for the lipid extraction process, ranging from 0.0531 to 0.0681 s−1. Considering its energy-efficiency and potential for scale-up, the one-pot manner may be a promising method to achieve industrial-scale lipid extraction from wet biomass.

The commonly used Pt/C catalyst has low durability for oxygen reduction reaction (ORR). In this work, CNT-supported TiO2 nanoparticles, which synergistically combines the merits of TiO2 (high stability and strong interactions with the supported Pt nanoparticles) and CNT (high specific surface area and large electrical conductivity), are prepared by a sol-gel process coupled with an annealing process and used as the support for Pt nanoparticles, which are anchored around TiO2 nanoparticles by a photodeposition technique. The as-synthesized Pt/TiO2@CNT catalyst exhibits a mass activity 5.3 times as large as that of the commercial Pt/C catalyst (0.358 A mgPt−1 vs. 0.067 A mgPt−1 at 0.9 V) and an excellent stability (no activity loss after 10000 potential cycles) for ORR, which can be mainly attributed to the lower oxygen adsorption energy of Pt, resulting from the strong metal-support interaction induced by the deposition of Pt nanoparticles around the well-dispersed TiO2 nanoparticles on CNT.

Among the Fischer-Tropsch synthesis (FTS) catalysts, Cobalt catalysts are currently attracting a lot of research interests due to their high activity and high selectivity. But the dispersion and reducibility of cobalt catalysts with moderate interaction between cobalt and support are still a challenge. A novel amino-ended hyperbranched polyamide (AEHPA) was used to modify SBA-15 and then was applied as support for obtaining cobalt catalyst (15Co/SBA-15-N). The catalysts were characterized by XRD, TEM, XPS and H2-TPR techniques. The results showed that AEHPA doped mesoporous SBA-15 caused the generation of N species in the SBA-15 pore channels. The N-Co bonds resulted in the formation of highly-dispersed cobalt nanoparticles with uniform sizes inside the ordered mesopores of support. AEHPA doping was an effective way to modify the surface properties of the SBA-15 for immobilizing cobalt nanoparticles. Compared with the conventional 15Co/SBA-15 catalyst without doping AEHPA, the AEHPA doped 15Co/SBA-15-N catalyst showed improved cobalt dispersion and stabilized cobalt location, which led to much better reaction stability as well as C5+ selectivity.

Black soldier fly larvae containing high lipids had been considered an novel sustainable feedstock for lipid extraction to biofuels. The insect lipid was extracted with microwave assisted solvent extraction method. The energy consumption of this way was analyzed to determine the feasibility of the lipid extraction process. The comparison of the effects of different extraction conditions (dehydration methods, water content, extraction temperature, extraction time, equipment power, and solute-solvent ratio) on the energy consumption of lipid extraction from the energy insect was investigated systematically. The dewatering of the insect biomass was the most energy consuming step via a dry extraction method in this paper, constituting about 40–80% of the total energy consumption demand. Within the ranges of extraction factors values compared in this analysis, the microwave radiation powder and lipid extraction temperature had a pronounced effect on the total energy consumption in the ranges of investigated parameter. At last, the lipid extraction yield-dependent evolution of energy consumption for different extraction conditions was also investigated. Anyway, the economic and environmental aspects of lipid extraction from the energy insect needed to be further improved for its large scale implementation in the future.

ZSM-5 seeds grafted mesoporous aluminosilicates with different morphologies (SZM-1 (two-dimensional (2D) structure), MZM-2 (three-dimensional (3D) structure), MZM-1 (mixture of 2D and 3D structure)) were synthesized by varying benzene addition amount. These composites were used as supports for Co (20 wt%) catalysts, which were prepared by simple incipient wetness impregnation method. Their catalytic performance was evaluated by Fischer–Tropsch synthesis (FTS) reaction. The supports and corresponding catalysts were characterized by N2 adsorption–desorption, XRD, TEM, H2-TPR, NH3-TPD techniques. 20Co/SZM-1 catalyst showed a highest FTS activity and best reaction stability, due to its higher cobalt dispersion, good cobalt reducibility and the confinement effect of two-dimensional structure. Compared to 20Co/SZM-1, 20Co/MZM-2 catalyst exhibited much higher selectivities to short-chain hydrocarbons and iso-paraffins, which may be attributed to the combination effects of its three-dimensional open pore structure and stronger acidity, leading to less diffusion limitation of hydrocarbon products and thus presenting a smaller chain-growth probability.

Nitrogen-doped carbon (N–C) materials are promising low-cost catalysts for oxygen reduction reaction (ORR). However, the commonly used route for N–C synthesis, viz., the high-temperature pyrolysis of N- and C-containing precursors, usually results in a great loss of N-containing species determining the ORR catalytic performance. Herein, porous N–C materials are synthesized by using g-C3N4 embedded in glucose-derived carbon as template and N source. The N–C sample synthesized at 900 °C with a mass ratio of glucose to g-C3N4 being 4:1 exhibits a positive half-wave potential (E1/2 = 0.823 V), good long-term stability and dominant 4 e− pathway for ORR in alkaline media, which can be attributed to its large specific surface area, high porosity, and large fraction of pyridinic and graphitic N. When a small amount of Fe is doped into the N–C sample, its ORR performance can be greatly improved and outperforms the commercial Pt/C catalyst in terms of ORR activity (E1/2 = 0.880 V), long-term stability and methanol tolerance. Notably, primary Zn-air batteries with N–C and Fe–N–C being the cathode catalysts exhibit peak power densities of 88 and 100 mW cm−2, respectively. This work offers a promising route for the synthesis of porous carbon-based materials highly efficient as ORR catalyst for Zn-air battery.

The concentrations of P and K in leaching solution are relatively low and the consumption of acid is relatively large, which are the existing problems in the leaching of P and K from P-K associated ore by using the low-temperature acid leaching process. In this work, a sequential leaching process with leachate recycling was developed, in which P and K were sequentially leached out from P-K associated ore and the obtained P- and K-containing leachates were recycled into the next leaching process. In this sequential process with leachate recycled two times the concentrations of K and P2O5 in leachate were increased from 20.18 and 15.79 g/L to 53.26 and 45.97 g/L, respectively. In comparison, in the simultaneous leaching process with leachate recycling both the leaching efficiencies of K and P and the concentrations of K and P2O5 were significantly lower than those in the sequential leaching process, which can be mainly attributed to the fact that Ca in the ore, which could react with PO43− to generate Ca-containing sediments, was precipitated first in the sequential leaching process. The sequential leaching process with leachate recycling will provide an efficient method for leaching and concentrating P and K from P-K associated ore.

Microseismic monitoring has been widely used in mines for monitoring and predicting dynamic disasters such as rockbursts and waterbursts. However, to develop high-precision microseismic monitoring systems, the propagation patterns of microseismic waves under complex geological conditions must be elucidated. To achieve this aim, a simulation model of a typical coalmine was designed using similar materials according to the similarity theory to simulate the mining process. Geophones were embedded into the model to detect the propagation of elastic waves from microseisms. The results show that in an unmined solid rock mass, the wave velocity in shallow rock strata is mainly affected by geologically weak planes, whereas in deep strata it is affected mainly by the density of the rock mass. During propagation, the amplitude first decreases and then increases rapidly with increasing propagation distance from the coal layer. After mining, our results indicate that the goaf causes significant attenuation of the wave velocity. After the goaf was backfilled, the velocity attenuation is reduced to some extent but not eliminated. The results of this study can be used as guidelines for designing and applying microseismic monitoring systems in mines.

The intensified leaching behavior of potassium from phosphorus-potassium associated ore in HCl-CaF2 system with different surfactants was investigated. It was found that anion surfactants could enhance the dissolution fraction of potassium and sodium dodecyl sulfate (SDS) had the best effect. The dissolution fraction increased from 89.50% to 98.01% with the addition of 0–1.25 g/L SDS, but dropped to 91.5% with 5.00 g/L SDS. The cationic surfactants could only shorten the time to the equilibrium, while the nonionic surfactant would hinder the leaching of potassium. The intensified leaching observed in the presence of 1.25 g/L SDS could be interpreted as follows: SDS was adsorbed on the surface and micro-porous cracks of mineral particles, then the adsorption film was appeared, which leaded to more SiF4 stayed in the adsorption film and more SiO2 produced, indicating the residual became smooth, thereby the ore was eroded thoroughly due to the produce of more HF. But much micelle covering on the residue was formed if the dosage such as 5.00 g/L SDS exceeded the critical micellization concentration (CMC), which hindered acid and fluorine entered into the interior of the ore, indicating dissolution fraction decreased. In addition, the leaching kinetics of potassium was successfully modeled by a semi-empirical kinetic model based on the modified shrinking-core model with chemical reaction being the rate-controlling step.

In this study, the mixed solvent of octanol (NOA) and methyl isobutyl ketone (MIBK) was used as extractant to purify wet process phosphoric acid from hydrochloric acid route. Densities and viscosities of leachate, extraction phase and raffinate phase were determined at 293–333 K, respectively. And the relation between density and temperature or phosphoric acid concentration can be expressed as a linear equation, with the maximum deviation of 0.0011 and 0.0027 g cm−3, respectively. Meanwhile, the viscosity of leachate, extraction phase and raffinate phase were measured since its importance on mass transfer occurred in the process of phosphoric acid extraction. And the relation between viscosity and temperature or phosphoric acid concentration can be summarized as a unitary quadratic equation, with the maximum deviation of 0.4489 and 0.1122 mPa·s, respectively. The results show that the densities and viscosities from experiment are generally in good agreement with calculated values from those equations obtained by regression analysis. The combined expanded uncertainty in the reported densities and viscosities are 0.3% and 5.5% of the measured values respectively, each with a coverage factor, k = 2.

Comb-shaped polysulfone anion exchange membranes (AEMs) containing various pendant alkyl side chains were synthesized and characterized. Ionic clusters aggregation is observed in transmission electron microscopy (TEM) image and small-angle X-ray scattering (SAXS). The comb-shaped quaternized ammonium polysulfone (Cx-QAPSU) membranes show enhanced dimensional stability and ultra-low membrane area resistance (Rm). Notably, the C16-QAPSU with 16 carbon atoms has the best hydrophilic-hydrophobic phase separation structure and lowest Rm of 2.5 Ω cm2 despite low ion exchange capacity (IEC) of 1.55 mmol/g and swelling ratio of 5.3%. Moreover, comb-shaped AEMs show much higher tensile strength (TS) compared to QAPSU membrane under the same IEC level. The C16-QAPSU with lowest Rm of 2.5 Ω cm2 exhibits the highest TS of 16.7 MPa. These results indicate that the long alkyl side chains especially the length of the pendant side chain of Cx-QAPSU up to C16 achieve an electrochemical-mechanical balance of AEMs. In electro-electrodialysis systems, the comb-shaped AEMs exhibit higher purification efficiency of wet phosphoric acid than non-comb-shaped AEMs.

Deep-sea mining extracts ores on the ocean floor. During this process the sea water may flood into the mine due to rockburst hazards. This study proposes an effective method to assess rockburst hazards using a self-developed real-time microseismic monitoring system in Sanshandao goldmine (the first undersea mine in China). In addition, the wave dissimilation patterns of this mine have been elucidated by analyzing the signals obtained by the geophones embedded in a similar material model. The monitoring work started in December 2014 and ended in March 2015 in Sanshandao goldmine. To assess rockburst hazards, this study proposes several indexes including spatial-temporal distribution of microseismic events, microseismic activity rate, energy release rate, continuity index, and average daily energy. The results show that the surrounding rock went through the stationary, active, secondary stationary, and secondary active periods before rockburst occurrence. Compared with the stationary period, a sudden change of the continuity index and average daily energy can be observed in the active period in which minor rockbursts constantly occurred. Rockburst accidents are very likely to occur in the secondary active period. However, before this period, there usually exists a secondary stationary period without rockburst risk. This study proposes a workflow for designing and applying microseismic monitoring systems.

The formation and development of faults are a manifestation of stress concentrations and energy release in crustal rocks, and faults have a great influence on the occurrence of dynamic mine disasters. This study proposed mapping technology as a fault identification method. The mapping procedure included four steps: (1) Drawing points on topographic maps. The information of topographic maps, such as elevation, rivers, and lakes was copied onto sulfuric acid paper. (2) Classifying the landform. Based on the highest and lowest points in the studied area, the minimum elevation difference was calculated and the elevation points were graded according to the minimum elevation difference. (3) Determining the block boundaries. The elevation points in the same grade were categorized into the same blocks. (4) Mapping the fault distribution. The boundaries between different blocks were considered as faults. In this regard, numbers were assigned to the faults, and a graphic scale, coordinate grid, and legends were added to the map. Fault identification for classes I–V was conducted at different scales. Fault identification for the next class always retained the previous results. Using this method, the faults in the Pingdingshan coal mining zone were divided into classes I–V. By comparing the classes with historical coal and gas outbursts, it was indicated that more than 90% of the coal and gas outbursts occurred in the vicinity of faults, especially at the intersections of multiple faults and in areas with concentrated faults. This study provided a scientific basis for predicting coal and gas outbursts.

Porous liquids, a new porous material with fluidity, can be applied in numerous fields, such as gas storage and/or separation. In this work, the separation of binary gas mixtures CO

To clarify the process of stress change and plastic zone evolution of square roadways under high-stress conditions, the rotational square expansion plastic zone evolution model of square roadway was established by theoretical analysis, numerical simulation, and engineering verification. The shear slip impact stress criterion of square roadway based on complex variable function theory was studied, and the law of surrounding rock stress distribution, plastic zone expansion, elastic energy density, local energy release rate (LERR), and total energy release of square roadway were analyzed. The results show that the compressive stress is concentrated in the four corners of the roadway after the roadway excavated and transfers with the change of plastic zone. Main shear failures start from the four corners and develop in a rotating square shape, forming square failure zones I and II. The square failure zone I is connected with the roadway contour and rotated 45°. The square failure zone II is connected with the square failure zone I and rotated 45°. When the original rock stress is low, the surrounding rock tends to be stable after the square shear slip line field formed. When the original rock stress is high, the shear failure of the surrounding rock continues to occur after the square failure zone II formed, showing a spiral slip line. Corners of the square roadway and square failure zones I and II are the main energy accumulation and release areas. The maximum elastic energy density and LERR increase exponentially with the ratio of vertical stress to uniaxial compressive strength (Ic). When square corners of the roof are changed to round corners, the plastic zone of the roof expands to form an arch structure. The maximum elastic energy density decreases by 22%, which reduces the energy level and possibility of rock burst. This study enriches the failure mechanism of roadway sliding impact. It can provide a basic theoretical reference for the design of the new roadway section and support form based on the prevention of rock burst.

Rock burst monitoring of heading face is a weak aspect of rock burst monitoring in China; acoustic emission (AE) monitoring is one of the few monitoring technologies used in heading face, but its target signals are small energy events which are easy to be disturbed. Researchers usually focus on the weak AE events but ignore the microseismic (MS) events (different from AE event and caused by a larger scale of coal fracture), while this kind of events can also reflect the pressure situation of heading face and have higher energy value which may become a better indicator for rock burst monitoring of heading face. So, the basic characteristics of MS events in heading face are studied based on a running vibration signal acquisition system, including the occurrence position, main frequency range, maximum amplitude (MA) range, event duration, and relationship with geological structure. This paper provides a development basis of the monitoring method for rock burst monitoring of heading face by using MS events.

Pyrolyzing precursors containing iron, nitrogen and carbon elements is a commonly used process for synthesizing Fe N C catalysts for oxygen reduction reaction (ORR). Generally, aggregation of iron-based species is prone to occur because of a lack of chemical bonds between iron-based species and carbon matrix and synthesizing highly porous Fe N C catalysts is difficult because carbon skeleton is prone to collapse during pyrolysis. Herein, highly porous Fe N C catalysts with fine iron-based species are synthesized by selecting glucose as carbon source, FeCl3 as iron source, and urea-derived g-C3N4 as nitrogen source, iron anchoring and stabilizing species, and pore-forming template. The multi-role g-C3N4-derived catalyst synthesized at 1100 °C (Fe N C 1100) has fine iron-based species, large specific surface area (737 m2 g−1), and extremely high pore volume (2.66 cm3 g−1). Accordingly, Fe N C 1100 shows a larger half-wave potential (E1/2 = 0.894 V), a higher stability (ΔE1/2 = 6 mV) after 10,000 potential cycles in alkaline media, and a higher peak power density (P = 152 mW cm−2) when employed as ORR catalyst of zinc-air battery, which are all superior to those of the commercial Pt/C catalyst (E1/2 = 0.864 V, ΔE1/2 = 30 mV, P = 134 mW cm−2). The present work brings a new method for synthesizing highly porous Fe N C catalysts decorated with fine active sites for ORR.