NH3 Treatment Research Articles

Gasotransmitter ammonia accelerates seed germination, seedling growth, and thermotolerance acquirement in maize

ABSTRACT Ammonia (NH3), as an intermediate product of nitrogen metabolism, is recognized as a novel gasotransmitter (namely gaseous signaling molecule), its signaling role being revealed in plants. NH3 exists in two different chemical forms, namely the weak base (free molecule: NH3) and the weak acid (ammonium: NH4 +), which are generally in equilibrium with each other in plants. However, the effect of NH3 on seed germination, seedling growth, and thermotolerance acquirement in maize remains unclear. Here, maize seeds were imbibed in the different concentrations of NH3·H2O (NH3 donor), and then germinated and calculated seed germination rate at the various time points. Also, the 60-h-old seedlings were irrigated in the different concentrations of NH3·H2O, and then subjected to heat stress and counted survival rate. The data implied that the appropriate concentrations (6, 9, and 12 mM) of NH3·H2O accelerated seed germination as well as increased seedling height and root length compared with the control without NH3 treatment. Also, the suitable concentrations (2 and 4 mM) of NH3·H2O improved tissue vitality, relieved an increase in malondialdehyde content, and enhanced survival rate of maize seedlings under heat stress compared with the control. These results firstly suggest that NH3 could accelerate seed germination, seedling growth, and thermotolerance acquirement in maize.

Regulation of bulk reconstruction of FeNiMoO4via NH3 treatment for high performance water oxidation

A Fe-doped NiMoO4 pre-catalyst with lattice defects induced by NH3 treatment shows bulk and rapid reconstruction to distorted γ-Ni(Fe)OOH with improved intrinsic activity for water oxidation.

Efficient degradation of emerging contaminant by newly-constructed Ni-CoO yolk-shell hollow sphere in the presence of peroxymonosulfate: Performance and mechanism

Constructing hollow structure is an effective strategy to boost the activity of heterogeneous catalysts in peroxymonosulfate (PMS) activation. Herein, a newly-designed Ni-CoO yolk-shell hollow sphere was first synthesized by a step-by-step method. Interestingly, the etching treatment of NH3·H2O endowed Ni-CoO sphere with hollow yolk-shelled structure, which was beneficial for the increase of specific surface area and the full exposure of active sites. The calcination treatment reduced the charge transfer resistance and enhanced the redox ability of Ni-CoO, further improving its catalytic activity. As expected, 93.1% of diclofenac sodium (DCF) could be rapidly degraded within 5 min over developed Ni-CoO-3/PMS system, and removal efficiency of TOC was as high as 73.3%. Significantly, redox couples of Co3+/Co2+ and Ni3+/Ni2+ were responsible for PMS activation based on radical pathways (namely SO4•−, OH• and O2•−). As the typical radical pathway, 1O2 was also involved in DCF degradation. More importantly, Ni-CoO-3-PMS* complexes mediated the direct electron transfer between DCF and PMS. Furthermore, Ni-CoO-3/PMS system with great stability had excellent practical application prospect in actual wastewater treatment. In short, current work not only offered a high-efficiency catalyst for PMS activation, but also shared some insights into the research on advanced oxidation processes.

Towards Improved Humidity Sensing Nanomaterials via Combined Electron and NH3 Treatment of Carbon-Rich FEBID Deposits.

Focused Electron Beam Induced Deposition (FEBID) is a unique tool to produce nanoscale materials. The resulting deposits can be used, for instance, as humidity or strain sensors. The humidity sensing concept relies on the fact that FEBID using organometallic precursors often yields deposits which consist of metal nanoparticles embedded in a carbonaceous matrix. The electrical conductivity of such materials is altered in the presence of polar molecules such as water. Herein, we provide evidence that the interaction with water can be enhanced by incorporating nitrogen in the deposit through post-deposition electron irradiation in presence of ammonia (NH3). This opens the perspective to improve and tune the properties of humidity sensors fabricated by FEBID. As a proof-of-concept experiment, we have prepared carbonaceous deposits by electron irradiation of adsorbed layers of three different precursors, namely, the aliphatic hydrocarbon n-pentane, a simple alkene (2-methyl-2-butene), and the potential Ru FEBID precursor bis(ethylcyclopentadienyl)ruthenium(II). In a subsequent processing step, we incorporated C-N bonds in the deposit by electron irradiation of adsorbed NH3. To test the resulting material with respect to its potential humidity sensing capabilities, we condensed sub-monolayer quantities of water (H2O) on the deposit and evaluated their thermal desorption behavior. The results confirm that the desorption temperature of H2O decisively depends on the degree of N incorporation into the carbonaceous residue which, in turn, depends on the chemical nature of the precursor used for deposition of the carbonaceous layer. We thus anticipate that the sensitivity of a FEBID-based humidity sensor can be tuned by a precisely timed post-deposition electron and NH3 processing step.

Amino-functionalized graphene oxide membranes for efficient separation of Sr2+ ions

Graphene oxide (GO) membranes were integrated with diverse nitrogen functional groups by subjecting to ammonia (NH3) vapours and evaluated for resultant changes in their chemical functioning and strontium (Sr) adsorption performance. Exposure to NH3 vapours amends the functional groups of GO, introduces amine, amide, ammonium functionalities and generates abundant sites prone to react with Sr2+ ions. The extent of GO restructuring and repercussions on Sr adsorption behaviour were examined using different GO precursors, NH3 treatment methods, membranes with varying GO mass and other nitrogen reagents namely, tri-isooctyl amine, pyridine, N,N-dimethyl acetamide. Nitrogen group functionalization enhances the Sr adsorption capacity of GO membranes nearly by two times, irrespective of the NH3 exposure duration and nature of precursor GO membranes. These NH3 subjected GO membranes displayed optimum Sr adsorption performance of ~475 mg/g, reusable at least for nine filtration cycles and importantly, capable of discharging 35–60 % of adsorbed Sr. The N-group supported Sr separation demonstrated in the present work is an energy efficient solid state membrane based procedure, which also lays a road map for development of amine, amide, ammonium functionalized GO layers and provides flexible platform for separation of all those toxic elements displaying affinity to complex with N-groups.

Amination of Polymeric Braid Structures to Improve Tendon Healing: An Experimental Comparison

AbstractSeveral polymers are researched for tendon repair as polyethylene terephthalate (PET) and polylactic acid (PLA). These are biocompatible and useful in scaffolding repair though with minimal success due to long‐term failure. There is a need to improve such scaffolds' design and physical–chemical nature. This work concerns surface functionalization of polymeric braids (PET and PLA) that fulfill the high mechanical demands of tissues such as tendons. The functionalization aims to incorporate amine groups in the braids' surface, improve cell adhesion, and consequently, the poor healing rate of these tissues and the biointegration of the braids. Two approaches are compared: the direct application of NH3 plasma and the surface grafting of EDA after O2 plasma activation. X‐ray photoelectron spectroscopy (XPS) shows that amine groups are effectively introduced onto the samples' surfaces. Besides, the plasma parameters chosen do not compromise the topography and tensile behavior of the braids. Resazurin assay and scanning electron microscopy show that the NH3 treatment improves cell–biomaterial interaction as improved cell adhesion and proliferation are observed. Both approaches are safe for biomedical applications. The NH3 plasma approach is more environmentally friendly, faster, and easier to scale‐up, showing potential for application in the final hybrid medical device.

Defective nano-structure regulating C-F bond for lithium/fluorinated carbon batteries with dual high-performance

Lithium/fluorinated carbon (Li/CFx) batteries show significant potential owing to high energy density and long-term storage performance. Restricted to the mutual restriction of F/C ratio and conductivity, the high energy density and power density cannot be achieved simultaneously. Herein, fluorinated honeycomb N-doped graphene (F-HNG) with conductive C-F bond was regulated by structural and heteroatomic defects, which was fabricated by nanoscale etching, NH3 treatment and gas phase fluorination. The unique pore provided smooth channels and storage sites for Li+ migration, while N atom with more electronegativity further regulated the charge distribution of the carbon skeleton. F-HNG delivered dual excellent electrochemical performance of a maximum energy density of 2595.47 Wh kg-1, associated with the unprecedented power density of 73.203 kW kg-1 at an ultrahigh rate of 50 C. Li/F-HNG pouch cell achieved an energy density of 707.52 Wh kg-1 with a mass loading of 10–15 mg cm-2 and reduced the heat release and battery swelling. In-depth density functional theory (DFT) calculations revealed that synergistic effect of porosity and N-doping regulated its C-F bond configuration, thermodynamic parameters, and ion diffusion pathway. This work indicates that nano-defect engineering and heteroatomic doping provide innovative possible directions for the design of CFx cathodes with dual superior performance.

P‐1.8: A New n + ‐Formation Process by NH 3 Plasma Treatment for Top Gate Coplanar IGZO Thin‐film Transistors

P‐1.8: A New n ⁺ ‐Formation Process by NH ₃ Plasma Treatment for Top Gate Coplanar IGZO Thin‐film Transistors

Defective structure of doped carbons obtained from preceramic polymers through Cl2‐ and NH3‐assisted thermolysis

AbstractThe processing parameters such as the heat treatment temperature, type of preceramic precursor, and post‐synthesis treatments are key factors for the development the different microstructures in polymer‐derived ceramics. Moreover, doping with different heteroatoms has increased the ability of the polymer‐derived ceramics to produce tunable nanostructures with a controlled pore size and distributions. A preceramic precursor containing P has been prepared from a commercial polysiloxane polymer and a phosphate alkoxide. It has been subjected to thermal treatments in N2, NH3, and Cl2 atmospheres in different order sequences to create differentiated microstructures either in the ceramic matrix and the carbon phase. The structural, textural, and spectroscopic characterization revealed that the P atoms play a key role in the evolution of the microstructure during the thermal treatments. If the chlorination is carried out before the treatment in NH3, a silicophosphate matrix is formed and prevents from nitrogen incorporation into the free carbon phase. On contrary, if the NH3 treatment is carried out before the chlorination, the carbon phase is predominantly modified by the incorporation of P atoms within the free carbon network.

Weakening the Metal–Support Interactions of M/CeO2 (M = Co, Fe, Ni) Using a NH3-Treated CeO2 Support for an Enhanced Water–Gas Shift Reaction

The metal–support interface plays a crucial role in heterogeneous catalysis. The modulation of the metal–support interaction (MSI) affords the possibility of promoting the catalytic efficiency per active site. Here, we report a strategy to modulate the interfacial interaction and then optimize the interfacial activity of Co/CeO2 catalysts for the water–gas shift reaction (WGSR) by a facile NH3 treatment process for the CeO2 support. The sample of Co/800N-CeO2 treated at 800 °C exhibited the highest reaction rate of 260 μmolCO/(gCo s), which was 23.8 times higher than the rate of the untreated Co/CeO2 sample. A combination of ex situ and in situ characterizations suggested that addition of the NH3 treatment process did not only weaken the metal–support interaction between the Co species and CeO2 support to strengthen CO adsorption and CO activation ability but also induced oxygen vacancy generation under reaction conditions to accelerate H2O activation. Both worked together in promoting the catalytic efficiency for the WGSR via the carboxyl pathway at a low temperature. It was worth mentioning that the N species of the CeO2 support introduced by the NH3 treatment was removed after changing the catalyst structure under reaction conditions. The interfacial structure was robust in a 60 h test at 400 °C due to the coexistence mechanism of carboxyl and formate pathways avoiding the poisoning effect of formate species on the active sites. The construction of active interfaces could be extended to Fe/CeO2 and Ni/CeO2 catalysts and could bring great promise in the design of the interfacial structure of supported catalysts in wide applications including chemical transformation reactions and industrial catalysis.

High-temperature solid-state rutile-to-anatase phase transformation in TiO2

TiO2 has many polymorphs, among which rutile is the most thermodynamically stable. Bulk anatase TiO2 is usually a metastable phase at room temperature. Hence, phase transformation of bulk rutile TiO2 to anatase TiO2 by heat treatment is thermodynamically forbidden. However, the stability of TiO2 polymorphs is dependent on particle size and doping level. In this work, we harnessed this characteristic to develop a solid-state high-temperature route of sequential NH3 and O2 treatment that transforms rutile TiO2 to anatase phase via grain fracture and N-doping. As an additional advantage, this technique produces a mixture of anatase and rutile phases, with anatase being a major phase. Biphasic TiO2 is advantageous from a charge separation perspective for photocatalytic applications. Furthermore, the bandgap of anatase TiO2 can be manipulated by controlling the O2 treatment time to tune it for specific applications.

Preparation of amide-enriched micro-mesoporous carbons from bayberry core via prepolymerization and ammonization co-treatment for high-performance supercapacitors

The rational design and synthesis of environmental, low-cost and eco-friendly renewable biomass-based carbons are highly desired for the development of high-performance supercapacitors. Herein, a novel amide-enriched synthesis strategy for biomass-based carbon from bayberry core (BC) by in-situ melamine-BC prepolymerization and subsequent NH3 ammonization. The synthesized biomass-based BC carbons were characterized by N2 adsorption/desorption, scanning electron microscope, Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results showed that the BC carbons by melamine and ammonization co-treatment had both much higher N-doping level (up to 6.43%) and surface area (up to 960 m2 g−1) than the N-free doped carbon. The doped N functional group was mainly dominated by the form of amide-N rather than pyridine-N or quaternary-N. More excitingly, the amide-N content increased with the extension of ammonization time while pyridine-N and quaternary-N went down. The prepared amide-enriched BC carbon via 20 g melamine pre-polymerization and 3 h ammonization treatment delivered an excellent specific capacitance of 259 F g−1, which was 35–72 F g−1 higher than the samples by 1h and 2h NH3 treatment though the latter two had much higher surface area, pyridine and quaternary-N content. The results indicated that the amide-N on the N-doped biomass-based carbon made a great role for enhancing the capacitance, and its promotion to electric double layer capacitance and pseudo-capacitance exceeded that of pyridine and quaternary-N.

Advancements of sequencing batch biofilm reactor for slaughterhouse wastewater assisted with response surface methodology

Slaughterhouse wastewater (SWW) contains a significant volume of highly polluted organic wastes. These include blood, fat, soluble proteins, colloidal particles, suspended materials, meat particles, and intestinal undigested food that consists of higher concentrations of organics such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen and phosphorus hence an efficient treatment is required before discharging into the water bodies. The effluent concentrations and performance of simultaneous sequential batch biofilm reactor (SBBR) with recycled plastic carrier media support are better than the local single-stage sequential batch reactor (SBR), which is lacking in the literature in terms of COD, NH3, NO3, and PO4 treatment efficiency. The present study reports a novel strategy to remove the above mentioned contaminants using an intermittently aerated SBBR with recycled plastic carrier media support along with simultaneous nitrification and denitrification. The central composite design was evaluated to optimize the treatment performance of seven different process variables including; different alternating conditions (Oxic/anoxic) for aeration cycles (3/2 h in a 6 h cycle, 6/5 h in a 12 h cycle and 9/8 h in an 18 h cycle) and hydraulic retention time (6, 12 and 18 h). The average removal efficiencies are 94.5% for NH3, 93% for NO3 and 90.1% for PO4, and 99% for COD. The study reveals that the denitrification in the post-anoxic phase was more efficient than the pre-anoxic phase for pollutant removal and maintaining higher quality effluent. The effluent concentrations and performance of simultaneous SBBR with recycled polyethylene carrier support media were better than local SBR system in terms of COD, NH3, NO3 and PO4 treatment efficiency. Results stipulated the suitability of SBBR for wastewater treatment and reusability as a sustainable approach for wastewater management under optimum conditions.

Room Temperature Operating, Fast and Reusable Polyaniline Sensor Synthesized Ultrasonically Using Organic and Inorganic Acid Dopants

In this paper we report a simple, green method for synthesis of polyaniline (PANI) nanoparticles by chemical oxidative polymerization with the assistance of ultrasonic irradiation. The polyaniline nanomaterials were synthesized with several organic acid dopants (tartaric acid (C4H6O6) and oxalic acid (C2H2O4)) and inorganic acid dopants (hydrochloric acid (HCl) and perchloric acid (HClO4)). A comparative study of the effect of the organic and inorganic acid dopants on the sensing properties of PANI for ammonia (NH3) vapors at room temperature was performed. It was observed that the electrical properties of the doped PANI depended on the type of the acid dopant. A remarkable change in resistance was observed upon doping with the different acid dopants. Structural and morphological studies and composition analysis were performed by UV-visible, FTIR, XRD and SEM techniques. The highest conductivity was obtained for PANI with HClO4 acid dopant while the lowest conductivity was obtained for PANI with tartaric acid dopant. The results showed that PANI doped with tartaric acid was an excellent sensor with fast response time and an enhanced sensitivity (26.1% for 5 ppm and 56% for 100 ppm) for NH3 gas at room temperature. PANI doped with organic acids showed faster recovery following NH3 treatment as compared to PANI doped with inorganic acid dopants. The PANI doped with tartaric acid sensor showed excellent stability for 350 days. In summary ultrasonic irradiation and the nature of the dopants showed significant effects on enhancing the sensing performance.

Treatment of phenols and NH3–N with activated carbon and polyurethane carrier in biological enrichment reactor

Coal pyrolysis wastewater contains a large number of phenols, ammonia, and various monocyclic and polycyclic aromatic compounds. In the study, activated carbon (AC) or polyurethane (PU) suspension carriers were comprehensively compared from efficiency, influencing factors, extracellular polymeric substances, and microbial population distribution to explore the suitable carrier in biological enrichment reactor the treatment of coal pyrolysis wastewater. In the start-up stage, the treatment effect of COD and total phenol (TPh) in the PU group (COD 86%, TPh 75%) was lower than that of the AC group (COD 94%, TPh 88%). However, with the loading of biofilm on PU, the treatment effects in the PU group began to improve. When COD was approximately 1000 mg/L and TPh was 500 mg/L, both the AC group and PU group showed sound treatment effects on COD (≥87%) and TPh (∼99%). Moreover, the PU group showed a higher removal effect of NH3–N (32.22%) and TN (30.85%). HRT should be 24 h to ensure partial degradation of organic matter and save carbon source dosage of the subsequent A/O treatment unit. Moreover, it had a removal effect on NH3–N and TN, which could effectively reduce the load of the subsequent multistage A/O treatment unit. The dominant functional bacteria in the AC and PU groups included Acidovorax, Alicycliphilus, Chryseobacterium, Rhodanobacter, and Thermomonas. Acidovorax, Alicycliphilus, and Chryseobacterium were the main functional bacteria involved in TPh and COD degradation. AC was suitable for rapidly reducing the concentration of pollutants or dealing with sudden increases in pollutants, while PU was more conducive to the long-term and stable operation of the biological enrichment reactor.

N-Doped Nanoporous Carbon Scaffolds As Catalysts for CO2 Reduction

The need for clean energy solutions in order to significantly lower our carbon footprint is placing increasing attention on renewable energy, such as wind and solar. However, these technologies suffer from intermittency issues, thus making efficient energy storage and conversion a major requirement. One of the solutions to this problem is electrochemical CO2 reduction (CO2RR), using renewable energy to produce green fuels and chemicals. However, the reduction of CO2 is thermodynamically and kinetically unfavorable. To overcome this, the development of highly efficient and selective electrocatalysts is a key goal of CO2RR research.Carbon has been attracting interest as a promising candidate due to its high specific surface area, good conductivity, and low-cost. However, its catalytic performance is limited by the electroneutrality of the carbon atoms in the primarily graphitic lattice. In order to activate the CO2 molecules and enhance the adsorption of intermediates, a range of novel carbon catalysts has been developed, with nitrogen doping being the most common approach. The N atom has a similar size as C and thus the lattice mismatch after doping is minimal [1]. At the same time, the N atom also has a higher electronegativity than C which will break the electroneutrality of the carbon lattice and enhance the conductivity of the material [2-3]. Furthermore, N doping results in a range of N-based surface species, thus potentially allowing the tuning of the CO2RR products [4].In this work, a novel, self-supported, nanoporous carbon scaffold (NCS) was used as the carbon substrate. The NCS is a templated, binder-free mesoporous carbon material with tunable pore sizes, a high surface area, good conductivity, and scalability [5]. Here, N doping of the NCS was achieved by heat treatment in NH3. An in house flow cell that can be switched between flow-through and flow-by modes was developed, allowing the NCS to be used as a model material to understand the impact of fluid flow on mass transfer limitations in the CO2RR and on any local pH effects that may be present.The CO2RR performance was tested in the flow cell using a CO2-saturated KHCO3 solution. The bare NCS was confirmed to generated only H2, while the N-doped NCS gives roughly a 50:50 ratio of H2:CO at all potentials, with the onset potential being ca. -0.55 V vs RHE. The effect of the NCS pore size was also investigated, showing that an NCS membrane with a nominal 85 nm pore diameter produced roughly 45% CO, while the NCS-12 (12 nm pore size) material gave somewhat more CO (ca. 55-60%). At the same time, the NCS-12 gave lower current densities, despite its higher surface area, likely due to poorer pore accessibility. Furthermore, running the cell in the flow-through mode gave higher currents at all of the NCS-based catalysts, most likely due to removal of trapped gases. Current work is focused on determining the effect of the N content and the type of N-based functionalities attached to the NCS surface on the CO2RR performance.

Manufacture of Carbon Materials with High Nitrogen Content.

Nowadays one of the biggest challenges for carbon materials is their use in CO2 capture and their use as electrocatalysts in the oxygen reduction reaction (ORR). In both cases, it is necessary to dope the carbon with nitrogen species. Conventional methods to prepare nitrogen doped carbons such as melamine carbonization or NH3 treatment generate nitrogen doped carbons with insufficient nitrogen content. In the present research, a series of activated carbons derived from MOFs (ZIF-8, ZIF-67) are presented. Activated carbons have been prepared in a single step, by pyrolysis of the MOF in an inert atmosphere, between 600 and 1000 °C. The carbons have a nitrogen content up to 20 at.% and a surface area up to 1000 m2/g. The presence of this nitrogen as pyridine or pyrrolic groups, and as quaternary nitrogen are responsible for the great adsorption capacity of CO2, especially the first two. The presence of Zn and Co generates very different carbonaceous structures. Zn generates a greater porosity development, which makes the doped carbons ideal for CO2 capture. Co generates more graphitized doped carbons, which make them suitable for their use in electrochemistry.

Enhanced interactions of gas molecule with defective graphene induced by strong coupling effect between carbon-Co in Co3O4: A theoretical study

The model of Co3O4 (110B)/defective graphene surface to adsorb NH3 is established. DFT calculation is conducted to study the effects of the defective graphene, Co3O4 (110B) and their coupling effect on adsorption for NH3 and the joint effects of pre-adsorbed O2/H2O on the model. The calculation results reveal the generation of C-Co coupling with Co3O4 (110B) at a specific Cooct site which enhances NH3 adsorption is related to graphene defects. Besides, C-Co coupling promotes the dissociative adsorption of pre-adsorbed O2 or H2O at Cooct site with C-Co and thus the formation of oxygen-containing functional groups such as C = O and C-OH group which produces an enhancement in stability of NH3 adsorption. Charge transfer amount in the NH3 adsorption process is enhanced by C-Co coupling effect, C atoms from graphene, lattice oxygen from Co3O4 and pre-adsorbed O2 or H2O. This work gives a better understand of influence factors of NH3 adsorption on Co3O4/graphene composite which is important for its catalytic reaction. It provides a theoretical basis for controlling catalytic reaction in NH3 treatment or sensing process.

Bifunctional Ni-Fe/NiMoNx nanosheets on Ni foam for high-efficiency and durable overall water splitting

Fabricating bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is challengeable. Herein, an efficient and durable bifunctional Ni-Fe/NiMoNx electrocatalyst has been synthesized on nickel foam. This electrocatalytic system exhibits significant HER and OER performances with overpotentials of 49 and 260 mV at 20 mA cm−2, respectively. For overall water splitting, Ni-Fe/NiMoNx electrodes require only 1.54 V for 10 mA cm−2. This enhanced HER and OER electrocatalytic performance is due to the combined effect of multiple active components formed after NH3 treatment. This work provides a new strategy for the rational design of bifunctional electrocatalysts for overall water splitting.

N-doped CoAl oxides from hydrotalcites with enhanced oxygen vacancies for excellent low-temperature propane oxidation

A series of nitrogen-doped CoAlO (N-CoAlO) were constructed by a hydrothermal route combined with a controllable NH3 treatment strategy. The effects of NH3 treatment on the physico-chemical properties and oxidation activities of N-CoAlO catalysts were investigated. In comparison to CoAlO, a smallest content decrease in surface Co3+ (serving as active sites) while a largest increased amount of surface Co2+ (contributing to oxygen species) are obtained over N-CoAlO/4h among the N-CoAlO catalysts. Meanwhile, a maximum N doping is found over N-CoAlO/4h. As a result, N-CoAlO/4h (under NH3 treatment at 400°C for 4 hr) with rich oxygen vacancies shows optimal catalytic activity, with a T90 (the temperature required to reach a 90% conversion of propane) at 266°C. The more oxygen vacancies are caused by the co-operative effects of N doping and suitable reduction of Co3+ for N-CoAlO/4h, leading to an enhanced oxygen mobility, which in turn promotes C3H8 total oxidation activity dominated by Langmuir-Hinshelwood mechanism. Moreover, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) analysis shows that N doping facilities the decomposition of intermediate species (propylene and formate) into CO2 over the catalyst surface of N-CoAlO/4h more easily. Our reported design in this work will provide a promising way to develop abundant oxygen vacancies of Co-based catalysts derived from hydrotalcites by a simple NH3 treatment.