INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Fengxian Zhang,Ye Chen,Yang Liu,Xupo Liu,Shuyan Gao
Constructing highly efficient and durable non-noble metal modified carbon catalysts for oxygen reduction reaction (ORR) in the whole pH range is essential for energy conversion devices but still remains a challenge. Herein, the Fe/Fe 3 C nanoparticles and Fe-N X species anchored on the interconnected mesoporous carbon materials are fabricated through an economical and facile template-assisted polymerization-pyrolysis strategy. The catalyst exhibits unique features with the electronic interaction between Fe/Fe 3 C and Fe−N X , large specific surface area and high mesoporous structure as well as nitrogen doping in porous carbon skeletons, which can effectively catalyze ORR over the full pH range. In an alkaline electrolyte , the optimized catalyst displays favorable ORR performance with positive onset potential ( E onset = 0.91 V), half-wave potential ( E 1/2 = 0.83 V), long-term cycles stability and methanol tolerance, exceeding those for the commercial Pt/C. Furthermore, the prepared catalyst could be directly assembled into the alkaline Zn−air battery that exhibits the open-circuit voltage of 1.44 V, high power density of 96.0 mW cm −2 and long-term durability. Therefore, the template-assisted polymerization-pyrolysis strategy provides a promising route for designing high-performance non-noble metal decorated ORR electrocatalysts .
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Zhe Xiong,Junhao Guo,Weerawut Chaiwat,Wei Deng,Xun Hu,Hengda Han,Yuanjing Chen,Kai Xu,Sheng Su,Song Hu,Yi Wang,Jun Xiang
The certain challenge for the utilization of bio-oil is to investigate the nature and formation of reactive large molecular (heavy) components (>200 Da) in bio-oil. In order to investigate the chemical composition of the heavy components in the bio-oils from the pyrolysis of cellulose , hemicellulose and lignin, the molecular formulas of the heavy compounds and the large aromatic structures were obtained based on the results from the Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) and the ultraviolet fluorescence (UV-F) spectrometer. The results indicated that both the oxygen content and yield of the heavy components showed the highest in the cellulose-oil and the lowest in the lignin-oil. The large molecular compounds were formed mainly via the recombination of the O-containing species, which could be changed at different temperatures and heating rates. Large amount of heavy saccharide and phenolic species existed in cellulose-oil and hemicellulose-oil, while almost no saccharide species and little phenolic species were detected in the lignin-oil. The main heavy components in the lignin-oil were lipids rather than the phenolic species. The heavy components in the bio-oil from the biomass should be mainly derived from the pyrolysis of the cellulose individually or the interactions among the three components.
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2018
·
IF 3.649
Kai Qiao,Feng Zhou,Zheng Han,Jie Fu,Huixia Ma,Guang Wu
Two series of ZSM-5 catalysts with hierarchical porosity were hydrothermally synthesized by adding two types of organosilane reagents (OSA) into the medial synthesis system. The effects of the types and addition amounts of OSA on the pore characteristics, crystallinity, morphology and acidity of the ZSM-5 zeolites were studied by XRD , SEM, TEM , N 2 -adsorption, 27 Al MAS NMR and NH 3 -TPD. Mesopores were generated by introducing appropriate amounts of OSA. In addition, the catalytic performance of the hierarchical ZSM-5s were investigated for the catalytic fast pyrolysis (CFP) of cellulose . The increase in the mesoporosity leads to a reduced amount of coke. However, the highest yield of aromatics was obtained for the mesoporous sample with the greatest microporosity. Thus, the right balance between meso- and microporosity is critical for achieving high aromatic yields. In addition, the distribution of aromatic products is directly related to the microporosity.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2017
·
IF 5.951
Lujiang Xu,Qian Yao,Ying Zhang,Yao Fu
Due to the irregular polymeric structure and carbon based inactive property, lignin valorization is very difficult. In this study we proposed a new route for lignin valorization by which aromatic amines can be directly produced from lignin by ex situ catalytic fast pyrolysis with ammonia over zeolite catalysts. Meanwhile, the obtained pyrolytic biochar can be activated to produce high surface area N-doped carbon for electrochemical application. Wheat straw lignin served as feed to optimize the pyrolysis conditions. MCM-41, β-zeolite, HZSM-5, HY, ZnO/HZSM-5, and ZnO/HY were screened, and ZnO/HZSM-5 (2 wt % Zn, Si/Al = 50) showed the optimal reactivity for producing aromatic amines due to the desired pore structure and acidity. Temperature, residence time, and ammonia content in the carrier gas displayed significant effects on the product distribution. The maximum yield of aromatic amines was obtained at moderate temperatures around 600 °C, 0.57 s, and 75% ammonia in the carrier gas. Under the optimized conditions, the total carbon yields of pyrolytic bio-oil and aromatic amines were 9.8% and 5.6%, respectively. The selectivity of aniline in the aromatic amines was up to 87.3%. Moreover, the pyrolysis byproduct, biochar, was further activated by KOH at 800 °C under ammonia atmosphere for producing N-doped carbon with high surface area. The pyrolytic biochar and N-doped carbon were characterized by elemental analysis, SEM, XRD, nitrogen adsorption–desorption, and XPS. Cyclic voltammetry (CV) and galvanostatic charge–discharge were employed to investigate the electrochemical performance of pyrolytic biochar and N-doped carbon. The specific capacitance of N-doped carbon reached about 128.4 F g–1.
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2024
·
IF 9
Liang Zhu,Wei Cai,Jie Li,Dengyu Chen,Zhongqing Ma
Co-catalytic fast pyrolysis of torrefaction deoxygenated pine wood (PW) and high-density polyethylene (HDPE) in dual-catalyst (metal oxidize and zeolite) system is an effective technology to produce renewable bio-aromatics. In this work, the torrefaction deoxygenation pretreatment (TDP) was carried out to remove oxygen element from PW prior to catalytic fast pyrolysis (CFP). 56.90 % oxygen could be removed at TDP temperature of 300 °C, releasing in the oxygen carrier of CO 2 , CO, H 2 O, alcohols, acids, phenols , etc. Then, the synergistic effect between the metal oxide and the HZSM-5 in dual-catalyst system was also investigated. Among these metal oxides (Al 2 O 3 , MgO, CaO, ZnO, and Fe 2 O 3 ) and hierarchical HZSM-5, the dual-catalyst of CaO and hierarchical HZSM-5 (treated by 0.2 M NaOH) was the optimal combination. The layout mode between feedstock and dual catalyst was also optimized. The highest yield of aromatics was produced in layout Mode 8, where the CaO was mixed with torrefied PW, but the hierarchical HZSM-5 and HDPE were laid in separated layers. The mixing of CaO and torrefied PW promoted the conversion of the macromolecular oxygenates into micromolecular oxygenates. Then, these small-molecular oxygenates could enter the hierarchical channel of HZSM-5, being converted into aromatics by undergoing the Diels-Alder reaction.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Bin Zhang,Ya’nan Li,Shuai Lu,Jonathan Richard Ishengoma,Song Wang,Jie Liu,Tao Tang,Sanxi Li
Plastic waste causes serious pollution to the environment. Being not satisfied with simply disposing of them into environment, people want to efficiently convert it into high-value products, such as H 2 and carbon nanotubes . A trimetallic catalyst is provided herein, which adds Pr, Ce, La or Yb to a Co-Fe bimetallic catalyst to inhibit the formation of oil by-product in a plastic pyrolysis reaction. In this work,various plastics，including plastics with different functional groups and real plastic waste were used for pyrolysis with elemental hydrogen efficiencies above 95% in the gas product. For pyrolysis of EVA, the gaseous hydrogen efficiency reached 96.07%, and for pyrolysis of LLDPE , the gaseous hydrogen efficiency reached 95.56%, over Pr 1 Co 1 Fe 8 O x catalyst. The role of Pr in catalytic reactions is discussed in general and the formation of carbon nanotubes of various types of structures is simulated. Catalyst cycling experiments demonstrate that the catalyst still maintains a gas hydrogen efficiency of more than 70% after being used four times. In conclusion, the Pr 1 Co 1 Fe 8 O x catalyst proved to be the best choice for microwave-assisted catalytic pyrolysis of plastics to H 2 , and this work provides a new perspect for the study of plastic pyrolysis.
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2018
·Vol. 11
·期 3
·1490-1499
·
IF 7.994
Du Haoran,Huang Kuangfu,Li Min,Xia Yuanyuan,Sun Yixuan,Yu Mengkang,Geng Baoyou
Porous hollow Co 3 O 4 microspheres have been synthesized from a mixed cobalt nitrate and urea solution through spray pyrolysis followed by calcination at 600 °C in air. This porous hollow Co 3 O 4 is assembled by nanoparticles and exhibits variable porosity depending on the amount of gas in the system. In pyrolysis process, urea continuously decomposes into gaseous components, which act as a template to control the porous structure. The amount of gas escaping from precursor droplets can directly influence the porosity of the microspheres and the size of the nanoparticles controlled by the ratio of urea to cobalt nitrate. Electrochemical measurements show that the performance of the porous hollow Co 3 O 4 microspheres is related to the porosity and size of the nanoparticles. The sample with optimal porosity delivers a high first charge capacity of 1,417.9 mAh·g −1 at 0.2C (1C = 890 mA·g −1 ), and superior charge cycle performance of 1,012.7 mAh·g −1 after 100 cycles. In addition, the optimized material displays satisfactory rate performance of 1,012.4 mAh·g −1 at 1C after 50 cycles and 881.3 mAh·g −1 at 2C after 300 cycles. Superior charge/discharge capacity, excellent rate performance and high yield achieved in this study is promising for the development of high-performance Co 3 O 4 anode materials for lithium-ion batteries.
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2024
·
IF 9
Xiaohua Li,Junlong Wang,Yongbo Yu,Yu Cao,Shanshan Shao,Shiliang Wu
Inexpensive catalyst sources are of great importance in the conversion of biomass to economically valuable monocyclic aromatic hydrocarbons , and transition metals (Co, Ni, Fe and Mn) rich in catalytic effects in massive waste lithium battery cathode materials are not effectively reutilized currently. For this reason, the feasibility of employing the valuable metal oxides in the carbon-reduced waste lithium battery cathode materials (waste LiFePO 4 batteries, LFP, and waste LiNi x Co y Mn 1–x–y O 2 batteries, NCM) with HZSM-5 as coupled catalysts in the rape straw catalytic pyrolysis to produce aromatic hydrocarbons was explored. The carbon-reduced waste lithium battery cathode materials performed well at 5 wt% carbon loading, and the content of active components Fe 2 O 3 (SLFPC-5) and NiO (SNCMC-5) used for the reduction of large molecular oxygenates in biomass pyrolysis gas was increased by water leaching treatment. SLFPC-5 demonstrated superior bond-cutting performance, while SNCMC-5 exhibited strong deoxygenation performance. The selectivity of monocyclic aromatic hydrocarbons (MAHs) catalyzed by SLFPC-5/HZSM-5 and SNCMC-5/HZSM-5 was as high as 63.69 % and 79.19 %, with BTX yields of 14.58 wt% and 16.68 wt% respectively. This coupled catalytic system offers a low-cost source of catalysts for biomass catalytic pyrolysis and broadens the possibility of high-value recycling of wasted lithium batteries.
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Fengdan Zhu,Chang Liu,Desheng Yang,Chaofei Bai,Xinlong Zeng,Ziteng Niu,Guoping Li,Yunjun Luo
Nitro complexes (NCs) have been selected as combustion catalysts for propellants due to their synergistic behavior. However, NCs prepared by traditional methods suffer from poor dispersion and irregular shape, which limit their catalytic potential. Hence, a polymer-assisted anti-solvent crystallization (PAASC) strategy was developed to fabricate potassium barium hexanitronickelate (K 2 Ba[Ni(NO 2 ) 6 ], PBHNN) crystals. In this method, emulsion particles created by mixing the solvent with the poor solvent serve as spherical templates. The particle size and monodispersity of PBHNN are controlled by PVP content. With 0.042 mol/L PVP, PBHNN were monodisperse with a particle size of 1.05±0.03 μm, which showed the best catalytic behavior for increasing the exothermic amount of hexanitrohexaazaisowurtzitane (HNIW) by 100.6 %. The high catalytic performance is due to the large specific surface area and improved contact efficiency. The in-situ TG-FTIR-MS test revealed that the procedure of PBHNN enhanced the pyrolysis of HNIW. The N-NO 2 bonds of HNIW are weakened by the strong attraction of metal oxides to electrons, which accelerates the formation of NO 2 . Consequently, increased NO 2 promotes subsequent oxidation reactions and improves the pyrolysis efficiency of individual HNIW. Therefore, the PAASC method is crucial for the fabrication of spherical monodisperse NCs with uniform particle size and high catalytic activity.
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2025
·
IF 7.5
Dongju Fu,Zhao Hu,Jinghui Xun,Xiao Yu,LuYang Wang,Shaozhong Zeng,Fengjiao Li
Highly ordered Pt alloy structure is an effective method to improve the catalytic activity and stability of cathodic oxygen reduction reaction (ORR) in acidic media, which is of great significance for the large-scale commercial application of proton exchange membrane fuel cells (PEMFCs). Herein, a highly efficient and durable catalyst composed of structurally ordered PtCo alloys with nitrogen-doped carbon (NC) shells is designed by improving the impregnation reduction method, using an intermediate self-sacrificial template strategy. Under the optimal preparation conditions of 20 wt% doped Ketjen black and a calcination temperature of 850 °C, the ordered PtCo alloy-based catalyst (denoted as L 1 0 -PtCo/ZNC) is obtained with an average nanoalloy size of about 3.9 nm and uniformly loaded on the N-doped carbon support via pyrolysis of cobalt-based zeolite imidazolate framework (ZIF-67) and carbon black. The half-wave potential ( E 1/2 ) of L 1 0 -PtCo/ZNC reaches 0.927 V vs. RHE, outperforming most of the reported catalysts and the benchmark commercial Pt/C catalyst. Moreover, the mass activity (MA, 1.06 A mg Pt -1 ) and specific activity (SA, 1.03 mA cm -2 Pt ) of L 1 0 -PtCo/ZNC are 7.6 and 4.7 times of those of Pt/C, respectively. The MA and SA values of L 1 0 -PtCo/ZNC after 10,000 cycles are 35 and 23 times of those of Pt/C catalysts, respectively, indicative of the excellent durability of L 1 0 -PtCo/ZNC. This method provides an effective strategy in preparing highly active and stable ordered PtCo alloy-based hybrid catalysts for acid ORR.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2025
·
IF 6.2
Ziwen Zhao,Hong Tian,Zhengye Chen,Zhangjun Huang,Shan Cheng,Siying Liu
This study employed torrefied wheat straw (260°C) as feedstock to synthesise a bifunctional metal-modified composite zeolite catalyst through alkali treatment (NaOH), dual metal loading (Fe and Ni), and hierarchical MCM-41 construction. Catalytically assisted pyrolysis behaviour was investigated using a tube furnace and Py-GC/MS system, evaluating the effects of pyrolysis temperature and catalyst/feedstock mixing ratio on product distribution and bio-oil composition. Results indicate that at a catalyst/feedstock ratio of 3:2, bio-oil yield peaked at 28.41% at 500°C, concurrently achieving a maximum monocyclic aromatic content of 66.36%. Elevating pyrolysis temperature promoted aromatic formation while significantly suppressing oxygenated compounds; notably, phenolic components decreased by 13.94% at 500°C, indicating the 1Ni1FeHR@M catalyst's potent deoxygenation capability. Further optimisation of the catalyst/feedstock blending ratio revealed that a 3:2 ratio yielded the highest combined bio-oil and monocyclic aromatic hydrocarbon production (18.62%), confirming this catalytic strategy effectively shifts the product distribution towards higher-value hydrocarbon fuels.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Wenjun Fu,Juan Luo,Shichang Shun,Jiangyi Luo,Chengling Liu,Rui Ma
The release of elemental chlorine in the form of HCl and the low quality of the product in the pyrolysis process of polyvinyl chloride (PVC) are constraints to its resource application. Furthermore, the regulation of chlorine migration and conversion processes also requires urgent attention. To address these shortcomings, we selected five metal oxides (M x O y ), namely MgO, CaO, Fe 2 O 3 , CuO, and ZnO, to construct an M x O y catalyst system with the functions of microwave absorption-catalysis-chlorine fixation. By discussing the composition of pyrolysis products, dielectric property analysis, oxygen vacancy (OV) defect analysis, and density functional theory (DFT) calculations under different catalyst systems, the mechanism of microwave absorption-catalysis-chlorine fixation was revealed. The results showed that ZnO had outstanding performance in microwave absorption, catalysis, and chlorine fixation: the optimal microwave absorption of ZnO increased the heating rate by 30 % (up to 19.67 °C/min) compared with the pyrolysis of PVC alone. The excellent O V content significantly catalyzed the C C bond breaking and dehydrogenation, reaction and facilitated the generation of lightweight products dominated by H 2 and CO. The chlorination reaction between ZnO and HCl had a lower reaction energy barrier, achieving a solid chlorine efficiency of 75.02 %. This work systematically evaluated and elucidated the trifunctional performance and mechanism of M x O y during low-temperature microwave pyrolysis of PVC.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）