CHEMICAL ENGINEERING JOURNAL
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2026
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IF 12.5
Jinchang Xu,Yinlong Wu,Tianli He,Ruizhong Chen,Siguo He,Jian Chen,Fangyan Xie,Yanshuo Jin,Ming-Hsien Lee,Nan Wang,Zhenyou Wang,Hui Meng
Dual nitrogen-doping strategies effectively regulate both the activity and durability of Fe-N-C catalysts. • Amino-functionalized precursors generate lower-coordinated Fe N sites, leading to enhanced ORR kinetics. • Ammonia-assisted pyrolysis boosts initial PEMFC performance by modulating spin state and increasing specific surface area. • The catalytic activity and stability of PEMFCs are strongly correlated with the spin state of the Fe active sites, where high-spin configurations offer higher activity but inferior stability. Nitrogen species play a crucial role in regulating the electronic structure of Fe-N-C catalysts, thereby governing the adsorption of oxygenated intermediates and ultimately determining proton exchange membrane fuel cell (PEMFC) performance. However, the intrinsic linkage among nitrogen configuration and catalytic performance remains insufficiently understood. To address this, we design four Fe-N-C catalysts with comparable structures but distinct nitrogen components by using amino-functionalized precursors and controlling the pyrolysis atmosphere. PEMFC testing and characterization show that amino groups in the iron precursor generate lower coordinated Fe-N x site, which density functional theory calculations show to possess more favorable adsorption energetics and reduced free-energy barriers for key reaction intermediates. In contrast, ammonia-assisted pyrolysis enhances initial performance primarily by introducing higher spin-state sites, abundant carbon defects, enlarging surface area, and increasing the density of accessible Fe-N x sites. Importantly, we find that both catalytic activity and durability can be regulated by Fe-N coordination by manipulating spin state of the Fe center: high-spin sites deliver higher intrinsic activity but suffer from accelerated degradation, whereas intermediate/low-spin sites offer improved stability. These findings suggest that a rational combination of precursor functionalization and pyrolysis atmosphere can simultaneously optimize Fe-N x site spin state, coordination environment, and carbon microstructure, providing a practical strategy to achieve both high activity and long-term durability in Fe-N-C catalysts for PEMFCs. Download: Download high-res image (57KB) Download: Download full-size image
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
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IF 12.5
Wei Feng,Xiaodong Chen,Jin Bai,Mo Zheng,Jinjun Guo,Congbin Jiang,Xianxian Zhang,Zongqing Bai,Wen Li
Integrating ReaxFF MD with TGA and in-situ Py-TOF-MS reveals synergistic mechanisms in co-pyrolysis of coal with HDPE, PP, and PS. • PP promotes C 5 -C 6 high-calorific gases, while PS enhances aromatics by cross-linking pathways. • PP promotes C C and C H cleavage while PS inhibits C O breaking and weakly promotes C H cleavage. • Coal/HDPE and coal/PP co-pyrolysis drive PAHs formation via Diels-Alder, alkylation, and aromatization reactions. • The polymer type critically determines the nature of the dominant reactive intermediates. Co -pyrolysis of low-rank coal and waste polymers offers a promising approach for plastic valorization while enhancing coal utilization and oil quality. In this work, the polymer types on the synergistic mechanism governing the co -pyrolysis of Zhundong low-rank coal and three typical polymers of HDPE, PP and PS were systematically investigated by integrating ReaxFF MD simulation with experiments of TG and in-situ Py-TOF-MS. It is observed that the temperatures of maximum weight loss ( T max ) follow the order of HDPE > PP > PS, consistently reproduced across three methods. PP addition promotes C 5 -C 6 high-caloric-value gases via long-chain cleavage while inhibiting the MAHs production. In contrast, PS facilitates phenolic hydroxyl removal from coal, promoting aromatic products. PS preferentially enhances light tar yield from 17.81% to 22.14%, whereas HDPE suppresses heavy tar yields from 39.90% to 35.56%. The ReaxFF MD simulation results further demonstrate the underlying molecular-scale mechanisms that are hardly accessible by experiments. HDPE and PP inhibit C O bond formation while promoting C H bond breaking during the co-pyrolysis. PP exhibits the strongest promotion of C-C/ C H cleavage, whereas PS shows the weakest effect on C H dissociation. During coal/HDPE and coal/PP co-pyrolysis, the formation of PAHs is promoted through Diels-Alder, alkylation and aromatization reactions. For coal/PS, the phenyl-alkyl radicals from PS combine with light tar, heavy tar, and char intermediates from coal to form cross-linked intermediates, facilitating cleavage of α -C ar -C al , β -C al -C al , and C ar -O bonds toward aromatics. The integrated strategy provides a comprehensive perspective for understanding co-pyrolysis mechanisms in other solid fuels and waste treatments. Download: Download high-res image (87KB) Download: Download full-size image
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Journal of Cleaner Production
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2023
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IF 11.1
Xiaohua Li,Ziheng Huang,Shanshan Shao,Yixi Cai
Theoretical and experimental study on the catalytic pyrolysis of rape straw was carried out for the production of aromatic hydrocarbons using the composite red mud (RM) and zeolite HZSM-5 catalyst as the combined catalysts. In the orthogonal tests and analysis of variance (ANOVA), it was originally established that Fe 2 O 3 and CaO acted as the active metal oxides in the red mud, which played the notable role in the production of benzene, toluene and xylene (BTX) as hydrocarbon fuels . Subsequently, the physicochemical property of the Fe 2 O 3 and CaO loaded red mud (Fe 2 O 3 -RM and CaO-RM) was investigated and their performance in the catalytic pyrolysis of rape straw combined with HZSM-5 were investigated. It was revealed that the further cracking of the primary pyrolysis gas was promoted with more active Fe 2 O 3 involved, and the heavy component was converted into the light fraction entering HZSM-5 for deoxygenation and aromatization to produce aromatic hydrocarbons. The yield of BTX over Fe 2 O 3 -RM was boosted by 10.15 wt% compared with the original red mud catalyst, while that of BTX was further promoted to 11.37 wt% over the composite red mud catalyst with 6% CaO loading. In addition to the strong bond-breaking performance of CaO, calcium carboxylate was easily generated and then decomposed to form CaCO 3 and ketones, and then BTX were produced from ketones over HZSM-5 by deoxygenation and aromatization. In this study, the high-performance red mud-based catalysts was designed and utilized in the thermochemical conversion of biomass, providing a potential way for the utilization of two solid wastes, rape straw and red mud to produce hydrocarbon fuels in a high-valued way.
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高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2022
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IF 7.926
Bo Jiang,Yunshu Zhang,Cong Li,Jiaqi Guo,Chunmeng Sun
Nanoscale zero-valent iron loaded on N-doped biochar (nZVI/NBC) is a novel catalyst for activating peroxydisulfate (PDS) toward efficient degradation of endocrine disruptors in water. In this study, spent coffee grounds were modified by K 2 FeO 4 and then transformed into nZVI/NBC by one-step pyrolysis . The nZVI/NBC modified with 0.3 mol/L K 2 FeO 4 displayed an excellent PDS activating performance, and the specific surface area and average pore width of this nZVI/NBC were 277.19 m 2 /g and 2.47 nm, respectively. Bisphenol A (BPA) as a typical endocrine disruptor can be efficiently degraded by nZVI/NBC/persulfate advanced oxidation process . The optimum dosage of nZVI/NBC was 0.1 g/L, and the optimum PDS concentration was 20 mM. pH (3−9) had little effect on BPA degradation. In addition, the presence of Cl − had a facilitating effect on BPA degradation, while CO 3 2− and HPO 4 2− had strong inhibitory effects. nZVI/NBC had long-term stability in that the activation rate remained stable after five cycles and 90 days of storage in air and natural light. This study also investigated the activation mechanism of PDS by nZVI/NBC and concluded that radical (•OH, SO 4 •− , and O 2 •− ) and non-radical ( 1 O 2 ) processes were simultaneously presented under the synergistic catalysis of ZVI and N. The formation of metastable PDS intermediates on the surface of biochar substantially enhanced the adsorption of PDS/BPA and the electron transfer process. Finally, the degradation pathways of BPA were speculated based on nine identified intermediates. Overall, this study described a rapid and green method for nZVI/NBC fabrication, which simultaneously achieved the recycling of spent coffee grounds and the degradation of endocrine disruptors in water.
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高影响因子
JOURNAL OF THE ENERGY INSTITUTE
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2019
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IF 3.774
Yunwu Zheng,Zhen Wang,Can Liu,Lei Tao,Yuanbo Huang,Zhifeng Zheng
By introducing exogenous nitrogen during biomass pyrolysis under nitrogen-rich conditions, high-value nitrogen-containing products, i.e., nitrogen-rich char and oil may be produced. Based on the cogeneration of high-value nitrogen products from biomass, biomass nitrogen-enriched pyrolysis was performed in a fixed bed with different sources and contents of ammonia. The yields, composition and characteristics of the products were investigated. Moreover, the formation mechanism of N-containing species was explored in depth for the pyrolysis and catalytic pyrolysis with HZSM-5 and Zn/HZSM-5 catalysts via elemental analysis, XPS, FTIR and BET. The results showed that ammonia impregnation could promote a Maillard reaction, reduce the content of small aldehydes and ketones, and produce a nitrogen-enriched bio-oil. The contents of N-containing species and phenolic substances in the pyrolysis oil of biomass impregnated with 10% urea reached 15.66% and 56.69%, respectively. Moreover, the nitrogen on the coke surface after pretreatment was mainly composed of C N, C N and N COO functional groups. The bio-char generated abundant pyridinic-N, pyrrolic-N, quaternary-N, and pyridone-N oxides. The presence of urea introduced many alkaline N-containing functional groups on the surface of the bio-char and promoted the transformation of nitrogen from amides and imides to heterocyclic nitrogen with higher thermal stability. Furthermore, Zn was an excellent catalyst for the Maillard reaction, and the Zn/HZSM-5 catalyst had a higher selectivity for aromatic hydrocarbons (96.98% for biomass and 86.48% for urea/biomass) and N-containing heterocyclic compounds, such as indoles (6.16% for biomass and 13.51% for urea/biomass). Additionally, the coke content decreased, and the catalyst deactivation decreased.
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高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2019
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IF 4.182
Hai-Tao Wang,Ya-Pan Liu,Hao Zhang,Na Chang,Wei Shao,Meng-Shan Shi,De Ao,Mei-Chan Lu
With the regular structures composed of metal clusters and organic ligands, metal-organic frameworks (MOFs) are expected to be the competent stabilizing matrix for nanoparticles and the excellent precursor of metal oxide with carbon species by means of high temperature pyrolysis , resulting to porous architectures with unexpected adsorptive or catalytic properties. Herein, we design and propose a facile route for preparing porous Carbon doped ZnO/TiO 2 @ZIF-8 (C–ZnO/TiO 2 @ZIF-8) multi-component nano-platform using TiO 2 coated ZIF-8 as precursor and template followed by thermal calcination . The resulted C–ZnO/TiO 2 @ZIF-8 nanocrystal simultaneously possesses original ZIF-8 morphology and porous structure with connected ZnO nanoparticles. As a result, C–ZnO/TiO 2 @ZIF-8 shows obviously better adsorption affinity towards methylene blue (MB). Moreover, benefit from the TiO 2 coating outside ZIF-8 matrix, escape of carbon species which originate from pyrolysis of organic ligands is efficiently inhibited, with the resulted materials doped with abundant carbon. Therefore, charge transfer and isolation of the resulted catalyst are promoted accordingly, with catalytic activity of the prepared C–ZnO/TiO 2 @ZIF-8 multi-component photocatalyst significantly increased by 1.8-fold and 3.0-fold compared to ZnO@ZIF-8 photocatalyst under irradiation of UV and visible light, respectively.
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高影响因子
FUEL
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2024
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IF 6.7
Anqi Li,Xiaoyu Qian,Mengyan Han,Zhichun Li,Xiaobo He,Guofeng Wang
Electrochemical catalytic water splitting is considered as a promising technique for green hydrogen production, and highly active catalysts toward cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) are required, especially bifunctional ones. In this work, the bifunctional catalysts with Co-CoO x @N, O co-doped carbon (NOC) hybrid nanostructures have been prepared via pyrolysis of ZIF-Co with assistance of a small amount of KNO 3 . KNO 3 plays important roles in tuning the inner and the outer structures of Co-CoO x @NOC hybrid nanostructures. The proposed S Ov , which is defined as the content of oxygen vacancy (O v ) per unit surface area of the inner Co-CoO x nanoparticle, and charge transfer resistance ( R ct ) are used as the descriptors of the inner structures, while hydrophilicity (or contact angle) is applied as the main feature of the outer structures. S Ov , R ct and hydrophilicity are well tuned by the fed mass of KNO 3 , and a moderate fed mass is the key to balancing S Ov , R ct and hydrophilicity and further is beneficial to accelerating specific and intrinsic activity for both HER and OER . Thus, the bifunctional HER/OER specific and intrinsic activity is peaked by Co-CoO x @NOC-0.025KNO 3 with a moderate fed mass of KNO 3 of 0.025 g, such as j s-250-HER of 539.22 μA cm -2 BET and j s-350-OER of 129.83 μA cm -2 BET at the HER and OER overpotentials of 250 and 350 mV, respectively, also corresponding to high turnover frequencies of 6.653 and 0.801 s −1 , respectively. The optimal catalyst also has high apparent activity, such as achieving high HER and OER current densities of 500 mA cm −2 , only requiring low overpotentials of 273.1 and 382 mV, respectively. It promotes overall water splitting with a high current density of 500 mA cm −2 at a cell voltage of ∼ 1.63 V, showing the high HER and OER Faradaic efficiencies of ∼ 98.2 and ∼ 98.0 %, respectively.
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高影响因子
CARBON
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2022
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IF 11.307
Jiao Li,Yuefan Wang,Chenxi Wang,Yilin Wang,Yaqi Yang,Jia Chen,Chunyan Li,Yixi Xie,Pengcheng Zhao,Junjie Fei
Baicalin obtained from natural plants has essential medical value, so the development of accurate and sensitive quantitative methods for it is one of the most important tasks. Here, the FeO X /Fe@porous carbon composite (Fe@C) was synthesized by solvothermal method and carbonized at different temperatures under an N 2 atmosphere, and an electrochemical sensor designed based on this material was applied to the accurate and rapid determination of baicalin. According to the results of physical and electrochemical characterization, Fe@C at different pyrolysis temperatures exhibited different morphologies and different electrochemical properties , while the Fe@C pyrolyzed at 800 °C had the optimum performance. Compared with NH 2 -MIL-88B, the pyrolysis greatly reduces the charge transfer internal resistance of the material and has a larger porosity and specific surface area, resulting in an eminent electrochemical signal for the detection of baicalin. The sensor Fe@C-800/GCE not only has a linear range of 4 nM–700 nM with a low limit of detection of 1.16 nM for the detection of baicalin, but also has outstanding repeatability, anti-interference and stability for the detection of baicalin in several natural plant samples and herbal medicines samples. This work presents several pyrolytic NH 2 -MIL-88B as electrochemical sensors for the detection of baicalin for the first time, providing a novel idea for the application of MOFs derivatives in environmental analysis.
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高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2025
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IF 3.7
Mengkun Luan,Wenli Su,Huijuan Guo,Yu Fan
ZSM-5 molecular sieves are potential catalysts for the catalytic pyrolysis of light naphtha. Nevertheless, traditional ZSM-5 is constrained by its low yield of light olefins and poor stability, limiting its use as a pyrolysis catalyst. In this work, a method involving quaternary ammonium salt (QAS)-assisted acid hydrolysis of silicon sources was developed to construct hierarchical and highly crystalline ZSM-5 molecular sieves for the efficient catalytic pyrolysis of n- pentane. The mesoporous sizes in hierarchical ZSM-5 were controlled by varying the alkyl chain length of the QASs. Diffusional measurements revealed that the diffusion time constant of n- pentane increased with increasing mesoporous size in ZSM-5. The n- pentane pyrolysis tests revealed that a suitable mesoporous size (10.8 nm) facilitated the n- pentane monomolecular cracking pathway while the hydrogen transfer reactions were inhibited. Among the series of ZSM-5 molecular sieves, the D-ZH5 catalyst synthesized by dodecyl trimethyl ammonium bromide (DTAB)-assisted acid hydrolysis of ethyl orthosilicate (TEOS) achieved the highest yields of light olefins (41.69% (mass) for ethylene and propylene) and the lowest deactivation rate (0.13%·h –1 ).
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高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2022
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IF 4.326
Li-Yun Zhang,Jing-Pei Cao,Xue-Yu Ren,Xiao-Bo Feng,Jing-Xian Wang,Zi-Meng He,Tian-Long Liu,Zhen Yang,Xiao-Yan Zhao,Hong-Cun Bai
CeO2 receives extensive researches as an active component due to its providential catalytic center and favorable reducibility. Herein, a series of Ce-modified hierarchical ZSM-5 zeolites (FZ5) were prepared by HF (0.5 mol/L) etching followed by impregnation with different Ce loadings. The role of incorporating extra-framework Ce elements was assessed by catalytic upgrading of the cellulose pyrolysis volatiles to produce light aromatics (LAs). Introducing CeO2 could effectively regulate the acid properties of catalysts with an increase in Lewis acid sites and a decrease in Brönsted acid sites, which could significantly improve the catalytic performance. As a result, the selectivity toward LAs were significantly enhanced and the coke content dramatically decreased. The highest selectivity to LAs and the lowest coke content obtained over 1.0Ce-FZ5 zeolite (loading 1.0 wt % Ce) were 84.0% and 2.42 wt %, respectively. Additionally, the 1.0Ce-FZ5 catalyst exhibited excellent stability, maintaining nearly 90% carbon yield of LAs after the seventh regeneration test. CeO2 modification opened a simple and feasible way for promoting the LAs selectivity and catalyst stability during the reforming of biomass volatiles.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Ouyang Haibo,Chen Zihao,Li Cuiyan,Shen Tianzhan,Wang Jintao,Chen Qianqian,Gao Ruinan
To address the rapid volatilization and decomposition of SiO 2 at ultra-high temperatures, a silicon-free strategy has been proposed for the design of C/C-(HfZrTi)C composites. These composites were fabricated using a precursor infiltration and pyrolysis method that employed metal chloride and furfuryl alcohol as precursors. The resulting C/C-(HfZrTi)C composites demonstrated exceptional ablation resistance, with a mass ablation rate of −0.567 mg/s and a linear ablation rate of 1.433 μm/s when exposed to a 2.4 MW/m² oxyacetylene flame. This enhanced ablation resistance is attributed to the formation of liquid TiO 2 during the ablation process. The liquid TiO 2 can penetrate oxide scales through capillary action, forming an oxygen diffusion barrier that inhibits the oxidation of the composites. Additionally, it can bond with solid (HfZr)O 2 particles, resulting in the formation of a dense (HfZrTi)O 2 oxide scale that improves resistance to flame scouring. This work provides a new method and strategy for the preparation and design of silicon-free composites for ultra-high temperature applications.
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高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2023
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IF 5.9
Donghua Li,Feng Shi,Meihua Fu,Yi Lu,Can Liu,Xu Lin,Defa Hou,Hao Sun,Cuiping Luo,Zhifeng Zheng,Yunwu Zheng
To unveil the nitrogen migration and conversion characteristics, catalytic copyrolysis of biomass pseudo components and polyamide (PA) with different blend ratios (1:0, 5:1, 3:1, 1:1, 1:3, 1:5, 0:1) under an ammonia atmosphere was proposed to boost the yield of N-containing compounds (NCCs) and N-rich biochar. The evolution and distribution of NCCs in liquid, gas and biochar were systematically investigated with a combination of TG-MS, Py-GC/MS and EPR. Synergistic effects and possible reaction pathways were also evaluated. Experimental results showed that PA could obviously boost biomass conversion due to increasing the chance of secondary cleavage, and the comprehensive synergistic effect of biomass-derived H* radicals, acid sites of the catalyst and cracking reactions (-C-N and C-C bonds) that reduced the reaction energy barrier and enhanced the NH 3 and HCN yields. NH 3 comes from the amino acids that are released from the amino acid pyrolysis and hydrolysis of HCN on the surface of char, while HCN is from the secondary cracking of primary pyrolysis products. Adding biomass increased CO 2 , CO, CH 4 , C-O and C O emissions from co-pyrolysis. Additionally, significant synergetic effects were observed when Biomass/PA= 3:1, which improved the NCCs and pyridine yields by 78.58% and 48.23%, respectively, under the HZSM-5 catalyst. A lower proportion of PA addition facilitated the Maillard reaction and amide bond cleavage to enhance the NCCs content and suppressed π-conjugated ring structure compound evolution and coke-derived O-containing compound polymerization, while a higher content of PA was favorable for amine and diaza heterocycle compound formation. Moreover, the addition of PA reduced the HHV and N content in biochar, resulting in lower pyrrole-N content and graphitization degree due to secondary cross-polymerization reaction of reaction volatiles, but it enhanced the polarity due to higher oxygen content (14.98%).
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高影响因子
危险品化学品经营许可证（带存储）