Environmental Progress & Sustainable Energy
·
2023
·
IF 2.8
Ping Gao,Xinshan Rong,Shixian Zhang,Ting Sun,Jun Liu,Xuchun Qiu,Xiangtong Zhou,Zhiren Wu,Jing Wei
Solar-driven reduction of nitrogen to ammonia is a promising green approach and is considered as a sustainable alternative to the Haber–Bosch process. Carbon nitride (g-C 3 N 4 ) is an ideal non-metallic semiconductor photocatalyst for photocatalytic N 2 reduction reaction (p-NRR). In this work, we designed a simple supramolecular self-assembly method to prepare copper-doped porous graphitic nitride (Cu@pg-C 3 N 4 ) photocatalysts. The synergistic semiconductor and metal interactions enabled the obtained Cu@pg-C 3 N 4 to achieve larger specific surface area, more efficient photogenerated carrier separation, and stronger photoreduction ability. The specific surface area of Cu@pg-C 3 N 4 increased from 5.69 to 75.76 μmol/L, exposing more active sites compared to bulk g-C 3 N 4 . The NH 4 + production rate of the obtained Cu@pg-C 3 N 4 was 150.47 μmol/L, which is 20 times higher than that of the bulk carbon nitride, exhibiting excellent N 2 photofixation ability. These findings highlight the significant progress that can be achieved by metal supramolecular network modification strategies in harnessing the potential of carbon nitride for photocatalytic reduction applications.
研究领域:
材料科学
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环境科学
·
化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Wenhao Zhang,Huan Li,Jianping Xiao,Xuefeng Zhu,Weishen Yang
Electrochemical ammonia synthesis (EAS) and nitrogen oxyanion / nitrogen oxides (NO x − /NO x ) conversion are important aspects of the artificial nitrogen cycle. Herein, we report a molten alkali electrolysis reactor for converting NO x − /NO x to NH 3 . A 110.3 ± 4.7 mg · h −1 · cm −2 yield of ammonia synthesis from nitrite was achieved with the Faradaic efficiency close to 100 %. By coupling NO oxidation with NO x − reduction, the NO conversion above 99 % was achieved with ammonia yield of 57.75 mg · h −1 · cm −2 . More importantly, the produced ammonia can escape from the electrolyte, thus avoiding the energy-consumed separation process. Revealed by density functional theory calculations, the excellent activity of EAS can be attributed to low barriers of electrochemical hydrogenation and the facile breaking of N O bonds with the assistance of Na/K cation at the interface. This work opens a new sight in EAS and enriches the artificial nitrogen cycle.
研究领域:
化学
·
电化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
Environmental Technology & Innovation
·
2021
·
IF 5.263
Juzheng Sun,Yangrui Huang,Huaizheng Li,Yiming Qiu,Jie Zhang,Kun Hu,Jiaying Li,Yuzhu Ding
Ammonia nitrogen (TAN) accumulated in the hydrosphere is an undesired nitrogen pollution and poses a great threat to both the ecological environment and human health. Its removal from water by the photocatalyst directly using solar energy is of strong interest in environmental remediation. In this study, graphitic carbon nitride (g- C 3 N 4 ) was combined with multiwall carbon nanotubes (CNTs) and loaded with silver nanoparticles (Ag (NPs) ) to hydrothermally synthesize a photocatalytic composite (Ag (NP) -(g- C 3 N 4 )/CNT) with a high catalytic efficiency. Characterization analyses indicated even deposition of Ag (NPs) onto (g-C 3 N 4 )/CNT composite by photochemical reduction and the increased photoresponse property compared with raw g-C 3 N 4 and TiO 2 -based materials. The photocatalysis of the composite was evaluated in terms of different Ag (NP) weight ratios, light intensities , photocatalyst dosages, solution pH values and light types. Results showed that a strong alkaline system induced a higher photocatalytic removal of TAN. The TAN removal ratio and rate constant at the optimal pH of 11 were 11.3 and 44.3 times those at a pH of 7. Compared with the process using g- C 3 N 4 alone (dosage = 0.5 g/L, initial TAN = 2.0 mg/L, pH = 11, Ag (NP) = 1 . 0 wt%), Ag (NP) -(g- C 3 N 4 )/CNT composite had effectively increased TAN removal and N 2 conversion ratios from 42.5% and 3.7% to 88.2% and 78.7 % upon 6-h Xe lamp irradiation (180 mW/cm 2 ). Ag (NP) -(g-C 3 N 4 )/CNT composite also exhibited satisfactory stability in cyclical TAN removal. Moreover, the mechanisms of TAN removal were analyzed. This study highlights the application of the Ag (NP) -(g-C 3 N 4 )/CNT composite as a potential method for ammonia removal in environmental remediation.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Environmental Technology & Innovation
·
2025
·
IF 7.1
Hua Huang,Xiaoyan Liu,Xianying Shan,Jingrong Yang,Lijuan Ding,Rongyu Zhang,Jiale Dai,Yanzhong Zhen,Jian Wang,Di Guo,Yu Liu,Wenfeng Jiang,Zhirui Niu
Since hydrothermal aqueous phase (HAP) contains abundant nutrients and humic-like substances, it is developed as nitrogen (N) fertilizer to improve plant growth and soil quality. However, significant NH 3 volatilization is a major drawback in dryland soil. To solve this problem, a compound fertilizer of HAP and urea was modified with various dosage (0.25 % - 5.0 %) of urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT). The NH 3 , N loss, and lettuce growth were evaluated in parallel soil column and pot experiments. Results showed that increasing NBPT dosage increased soil dissolved organic N (DON) and ON while decreased NH 4 -N, NH 3 , N loss, urease activity, and ureC . NBPT successfully inhibited ammonification. Increasing NBPT dosage increased NO 3 -N but decreased PAO and AOA . The utilization rate of metabolic substrate (NH 4 -N) was more important for forming NO 3 -N, as evidenced by the negative correlation of NO 3 -N and NH 3 . The DON from HAP included N-heterocyclic compounds, which are toxic for nitrifiers. The toxic DON also significantly decreased root dry weight by 22.31 % when 5.0 % NBPT was added. The optimal additive dosages were 0.5 % and 2.0 % in the column and pot experiments, respectively, which decreased NH 3 and N loss by 45.38 % and 32.08 %. Further increasing NBPT dosage no longer decreased N loss but did harm to plant root. Therefore, this study demonstrated that an appropriate addition of NBPT to HAP fertilizer can effectively reduce ammonia volatilization and N loss. The innovative technique would promote the utilization of HAP resource within the context of sustainable dryland agriculture.
研究领域:
农业科学
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植物生理学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Zuhao Chen,Yongyou Hu,Guanglei Qiu,Donghui Liang,Jianhua Cheng,Yuancai Chen,Xiaoqiang Zhu,Guobin Wang,Jieyun Xie
The effects of antibiotics, such as tetracycline, sulfamethoxazole, and ciprofloxacin, on functional microorganisms are of significant concern in wastewater treatment. This study observed that Acinetobacter indicus CZH-5 has a limited capacity to remove nitrogen and phosphorus using antibiotics (5 mg/L) as the sole carbon source. When sodium acetate was supplied (carbon/nitrogen ratio = 7), the average removal efficiencies of ammonia-N, total nitrogen, and orthophosphate-P increased to 52.46 %, 51.95 %, and 92.43 %, respectively. The average removal efficiencies of antibiotics were 84.85 % for tetracycline, 39.32 % for sulfamethoxazole, 18.85 % for ciprofloxacin, and 23.24 % for their mixtures. Increasing the carbon/nitrogen ratio to 20 further improved the average removal efficiencies to 72.61 % for total nitrogen and 97.62 % for orthophosphate-P (5 mg/L antibiotics). Additionally, the growth rate and pollutant removal by CZH-5 were unaffected by the presence of 0.1–1 mg/L antibiotics. Transcriptomic analysis revealed that the promoted translation of aceE , aarA , and gltA genes provided ATP and proton -motive forces. The nitrogen metabolism and polyphosphate genes were also affected. The expression of acetate kinase, dehydrogenase, flavin mononucleotide enzymes, and cytochrome P450 contributed to antibiotic degradation. Intermediate metabolites were investigated to determine the reaction pathways.
研究领域:
环境微生物学
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废水处理工程
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分子生物学
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DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 34
·19831-19837
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IF 10.733
Xiang-Wei Guo,Shuang-Ming Chen,Hong-Juan Wang,Zhi-Ming Zhang,Hong Lin,Li Song,Tong-Bu Lu
A series of Mo single-atom catalysts were prepared by calcining a low-cost primary material of urea with various amounts of Na2MoO4·2H2O. Isolated Mo centers are immobilized on in situ formed polymeric carbon nitride via coordinating with two N donors to form two-coordinated MoN2 species. The low-coordinated Mo centers can serve as active sites for N2 chemisorption and activation, achieving high photocatalytic activity for NH3 evolution with a rate of 50.9 μmol gcat−1 h−1 in pure water. In the presence of ethanol as the electron scavenger, the NH3 evolution rate can reach 830 μmol gcat−1 h−1, and the catalyst shows a quantum efficiency of 0.70% at 400 nm. This is the first single-atom catalyst that can drive photocatalytic N2 fixation in pure water with comparable performance to recent reports for photocatalytic N2 reduction. Experimental investigations and density functional theory calculations demonstrate that the coordinatively unsaturated metal center in the single-atom catalysts can strongly adsorb N2via an end-on configuration to elongate the NN bond from 1.11 Å to 1.15 Å, and thus photoexcited electrons can transfer to the weakened NN bond for efficient nitrogen fixation under ambient conditions. These findings provide new insight for solar-driven N2 fixation by atomically dispersing low-coordination metal centers on photoactive supports.
研究领域:
材料科学
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化学
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环境科学
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
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IF 6.14
Tao Zhou,Shuya Wu,Lianghu Su,Jianying Xiong,Youcai Zhao
Anaerobic fermentation liquid from food waste contains abundant nutrients, such as volatile fatty acids (VFAs) and NH3–N, which are promising nutrient sources for plant growth. Here, we report a novel integrated technique for the simultaneous recovery of C and N sources from anaerobic fermentation liquid. VFAs and NH3–N extracted from anaerobic fermentation liquid were synthesized and converted into layered double hydroxides (LDHs) and NH4HCO3, respectively, for subsequent use as soil amendments to provide external C and N to plants. The X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy/energy dispersive X-ray spectroscopy results suggested that VFAs were successfully intercalated within the LDH, and the composite (VFA-LDH) exhibited good sustained release performance. In the VFA-LDH synthesis process, the concentrations of chemical oxygen demand, VFAs, and NH3–N were reduced by 49.4%, 27.9%, and 43.6% in the anaerobic fermentation liquid, respectively. In addition, VFA-LDH and NH4HCO3 promoted increased soil fertility, including organic matter content, cation exchange capacity, and N and P contents. Overall, the developed technique exhibits great potential as an anaerobic fermentation liquid treatment and nutrient acquisition method.
研究领域:
环境科学
·
农业科学
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DOI
高影响因子
Metals
·
2020
·Vol. 10
·期 3
·356
·
IF 2.117
Yongjie Liu,Yue Wang,Zhixiong You,Xuewei Lv
The steel micro-alloyed with ferrovanadium nitride has extremely superior properties that make it widely utilized in structural components, construction and aircraft. The conventional methods for synthesizing ferrovanadium nitride include nitridation of pure ferrovanadium alloy or carbothermal nitridation of metallic oxides, using nitrogen or ammonia gas as nitrogen sources. In this study, ferrovanadium nitride (FeV45N) was prepared by direct reduction and nitridation of the corresponding metal oxides with ammonia as the reductant and nitrogen source. This method avoids the introduction of other impurity elements, except the negligible trace elements accompanied with the raw materials. The thermodynamics of the reduction and nitridation process were initially analyzed. During the subsequent ammonia reduction process, the FeV45N powders were successfully obtained at 1273 K for 6 h. The obtained powders were pressed into cylindrical briquettes by hot pressing (HP) at 1473 K for 1 h in vacuum. In the investigation, the X-ray diffraction and morphological analysis of the products was also carried out, and the reaction mechanisms were discussed in detail. The nitrogen content of the final product can reach 11.85 wt. %, and the residual oxygen content can be reduced to 0.25 wt. %. By sintering, the density of the alloy can reach 5.92 g/cm3.
研究领域:
材料科学
·
冶金工程
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DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2021
·
IF 5.039
Yongjie Liu,Ran Xin,Donglai Ma,Qingqing Hu,Yue Wang,Zhixiong You
Ferrovanadium nitride, which comprises V and N, is an important alloy additive for the production of high-strength low-alloy steel. As an efficient reducing agent and nitrogen source, ammonia gas is widely used in the preparation of metal nitrides. In this study, ferrovanadium nitride alloy powder is prepared by reducing and nitriding VO 2 /Fe 2 O 3 in NH 3 –H 2 gas mixtures with different nitriding potentials. Thermodynamic analysis indicate that the reduction and nitridation of VO 2 and Fe 2 O 3 is feasible. VO 2 is converted into VN, whereas Fe and Fe 4 N can be formed depend on the reaction conditions. Lower temperatures and higher nitriding potentials are beneficial to the formation of Fe 4 N. Based on Rietveld refinement analysis, the formation of Fe 4 N and the atomic occupancy of V and N in vanadium oxynitride, which is associated with the temperature, reaction time, and nitriding potential, is determined. A ferrovanadium nitride alloy powder with an O content of 0.26 wt.% is prepared by reducing and nitriding VO 2 /Fe 2 O 3 at 900 °C for 1 h at a nitriding potential of 4.4 × 10 −3 Pa −0.5 .
研究领域:
材料科学
·
冶金工程
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
·
IF 20.2
Wanyu Zhang,Huanhuan Bai,Bibo Ma,Lin Wang,Yumei Zhang,Qingzhi Luo,Jing An,Huiying Mu,Huaiyu Zhang,Yandong Duan,Desong Wang
Heterogeneous photocatalysis rarely employs main group metals as active centers due to the lack of available d orbitals. In this study, alkaline earth metal centers were introduced into a carbon-doped boron nitride framework, leading to an optimization of their electronic structure and successful activation of catalytic activity. Interestingly, these metal centers were found to effectively utilize d orbitals or d/p hybrid orbitals to activate O 2 and H 2 O, thereby generating a wealth of reactive oxygen species (ROS), which efficiently convert NO to NO 3 - . In addition, the optimized alkaline earth metal structural unit can not only strengthen carrier separation, but also improve the adsorption behavior of NO 2 on the catalyst surface and promote its further conversion to NO 3 - . This research provides new insights into the design of highly active sites and the exploration of catalytic mechanisms for alkaline earth metals.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2024
·
IF 11.2
Xue Li,Yulei Zhang,Yanqin Fu,Junhao Zhao,Jiachen Meng
Hafnium carbonitride (HfC x N 1– x ) ceramics have drawn considerable interest due to their exceptional mechanical and thermophysical properties. Herein, we report a novel single-source precursor with Hf–N bonds as the main chain and fabricate HfC x N 1– x ceramics after pyrolysis of the precursor. The synthesis, ceramic conversion, and microstructural evolution of the single-source precursor as well as the derived HfC x N 1– x ceramics treated under various atmospheres were investigated. The results indicate that in an argon atmosphere, the nitrogen content within HfC x N 1– x decreases with rising temperature. While under a nitrogen atmosphere, the high concentration of N 2 facilitates the rapid conversion of HfO 2 to Hf 7 O 8 N 4 , which subsequently promotes the transformation of the HfC x N 1– x solid solution ceramics. During this process, there is also an inhibitory effect of N 2 on the tendency of HfN into HfC. Moreover, the desired chemical composition of HfC x N 1– x can be regulated by adjusting the N 2 concentration in the heat treatment atmosphere. The present work proposes a novel strategy for the single-source precursor-derived carbonitride ceramics and provides a deep understanding of the preparation and property modulation of HfC x N 1– x ceramics.
研究领域:
材料科学
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陶瓷学
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产品关联
DOI
高影响因子
Toxics
·
2024
·Vol. 12
·期 5
·353
·
IF 3.9
Yuqi Zhu,Yili Zhang,Hui Chen,Lisha Zhang,Chensi Shen
The increasing concern over climate change has spurred significant interest in exploring the potential of microalgae for wastewater treatment. Among the various types of industrial wastewaters, high-salinity NH4+-N wastewater stands out as a common challenge. Investigating microalgae’s resilience to NH4+-N under high-salinity conditions and their efficacy in NH4+-N utilization is crucial for advancing industrial wastewater microalgae treatment technologies. This study evaluated the effectiveness of employing nitrogen-efficient microalgae, specificallyOocystis lacustris, for NH4+-N removal from saline wastewater. The results revealedOocystis lacustris’s tolerance to a Na2SO4concentration of 5 g/L. When the Na2SO4concentration reached 10 g/L, the growth inhibition experienced byOocystis lacustrisbegan to decrease on the 6th day of cultivation, with significant alleviation observed by the 7th day. Additionally, the toxic mechanism of saline NH4+-N wastewater onOocystis lacustriswas analyzed through various parameters, including chlorophyll-a, soluble protein, oxidative stress indicators, key nitrogen metabolism enzymes, and microscopic observations of algal cells. The results demonstrated that when theOocystis lacustriswas in the stationary growth phase with an initial density of 2 × 107cells/L, NH4+-N concentrations of 1, 5, and 10 mg/L achieved almost 100% removal of the microalgae on the 1st, 2nd, and 4th days of treatment, respectively. On the other hand, saline NH4+-N wastewater minimally impacted photosynthesis, protein synthesis, and antioxidant systems within algal cells. Additionally, NH4+-N within the cells was assimilated into glutamic acid through glutamate dehydrogenase-mediated pathways besides the conventional pathway involving NH4+-N conversion into glutamine and assimilation amino acids.
研究领域:
环境科学
·
微生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）