JOURNAL OF CHEMICAL SCIENCES
·
2022
·Vol. 134
·期 2
·1-11
·
IF 2.15
Yu Miao,Ji Shuai,Li Zhifang,Song Kun,Li Yueyu,Yang Jian,Yang Changlong
A simple ion-exchange method is used to prepare Mn and Co-supported TNU-9 denitration catalyst for NH 3 -SCR. The denitration activity and H 2 O/SO 2 resistance performance of the catalyst are systematically studied. The denitration activity test exhibits that the NO x removal rate of Mn-Co/TNU-9 is higher than that of Mn/TNU-9 and Co/TNU-9, the NO x removal rate is greater than 90% and the N 2 selectivity is greater than 99% in the range of 150 ~ 450 °C. It is because the redox cycle of Mn 4+ + Co 2+ ↔ Mn 3+ + Co 3+ improves the redox performance of the catalyst, which is conducive to the conduction of electrons, and then accelerates the oxidation of NO to NO 2 to produce a "fast SCR" reaction, and finally optimizes the overall SCR performance. Furthermore, the change is not significant for the catalytic activity over Mn-Co/TNU-9 in the presence of water. However, the sulfur resistance is poor at low temperatures due to the presence of ammonium bisulfate. It also has excellent catalytic stability. Therefore, supported TNU-9 catalysts will have a good development prospect in denitrification. Graphical abstract Mn-Co co-doped TNU-9 catalyst was successfully synthesized by simple ion exchange method and applied in the NH 3 -SCR. The results show that Mn-Co/TNU-9 catalyst has an excellent wide activity window in a wide temperature range of 150-450°C (NO x conversion over 90%), which is because Mn+Co 2+ ↔Mn+Co improves the redox performance and facilitates the electron transfer, which further accelerates the oxidation of NO into NO 2 that could result in the “Fast SCR” reaction. The synergistic effect between Mn and Co bimetallic can also improve activity. Moreover, Mn-Co/TNU-9 has very good catalytic stability.
✓ 已验证
DOI
高影响因子
WATER ENVIRONMENT RESEARCH
·
2022
·Vol. 94
·期 9
·e10788
·
IF 3.306
Binbin Shao,Yating Zhu,Jie Chen,Yimin Lin,Xiaohong Guan
During oxidative treatment of iodide (I − )-containing waters, I − is easy to be oxidized into hypoiodous acid (HOI) by various oxidants and the further reaction of HOI with organic compounds can lead to the formation of iodinated disinfection by-products (I-DBPs). Oxidation of HOI to iodate (IO 3 − ) or reduction of HOI to I − has been proposed to reduce the formation of I-DBPs. Because the reaction of HOI with sulfite proceeds rapidly, this study examined the fate of iodine and the formation of I-DBPs in Mn(VII)/sulfite process. Results showed that I − was oxidized to HOI but the further formation of IO 3 − was suppressed due to the fast reduction of HOI to I − by sulfite. The reactions of HOI with SO 3 2− and IO − with SO 3 2− are the major pathways with species-specific second-order rate constants determined to be 1.12 × 10 5 M −1 s −1 and 9.43 × 10 7 M −1 s −1 , respectively. The rapid reaction of HOI with sulfite plays an essential role in minimizing the formation of iodinated products in HOI- and phenol-containing solutions. The toxic risk analysis showed that the toxicity of the generated DBPs from Mn(VII)/sulfite pre-oxidation followed by chlorination only changed slightly. Practitioner Points The decay of I − was negligible in Mn(VII)/sulfite process. The rapid reaction of HOI with SO 3 2− resulted in the negligible generation of IO 3 − . Mn(VII)/sulfite process exerted slight influence on the formation of I-DBPs. Mn(VII)/sulfite process is promising for the pretreatment of I − -containing water.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Runren Jiang,Guanghua Lu,Min Wang,Tianjian Dang,Jianchao Liu,Zhenhua Yan
Utilizing photocatalysis to degrade pollution is emerging as a promising way to treat wastewater, but is challenged by low efficiency and scanty toxicity cognition. In this work, Mn 3 O 4 /BiOCl based crystal plane engineering systems are applied for naproxen (NPX) degradation, and Mn 3 O 4 /BiOCl 010 displayed better degradation rate, which is 16 and 8 times than that of the Mn 3 O 4 /BiOCl 001 and BiOCl 010 . According to the degradation pathway analysis and biological toxicity experiments, the toxicity of the degradation solution increased first and then decreased, which may be caused by the mineralization of NPX and more toxic intermediates. Affected by the distinct internal charge transfer directions of the two crystal planes of BiOCl, Mn 3 O 4 /BiOCl 010 heterojunction system has a faster charge transform than that of Mn 3 O 4 /BiOCl 001 . Moreover, the valence cycle of Mn can further accelerate the charge transfer, which can also provide a powerful driving force for NPX elimination.
✓ 已验证
产品关联
DOI
高影响因子
Nano Energy
·
2021
·
IF 17.881
Tao Huang,Hui Peng,Qilin Wei,Chengyu Peng,Ye Tian,Shangfei Yao,Xinxin Han,Bingsuo Zou
If we introduce transition metal ions with spins into an organic-inorganic halide perovskite compounds, interesting spin dependent optical properties may be seen in this system. This paper reports an organic-inorganic hybrid manganese ion doped lead halide crystal incorporated by TDMP (trans-2,5-dimethylpiperazinium), it gives not only the STE1 (polaronic exciton), usually brought up by the enhanced electron-phonon coupling in the amine incorporated compound, but also give a novel bipolaronic exciton (STE2) for the paired charge state formation due to the incorporation of bi-amine cationic molecules, a excitation by the polaronic molecule due to enhanced electron-phonon coupling and neighboring correlation out of the Mn ion ferromagnetic spin coupling in the lattice at slightly high doping. Such magnetic bipolaron state could often be accompanied by several multiphonon Raman modes and ferromagnetism. It is even interesting that this state can give super-high red emission with PLQY at ~92.5% at room temperature. Moreover, the emission color and intensity could also be modulated by the Mn doping concentration, temperature, and laser excitation power. The low doping products can give green emission out of single Mn d-d transition at very low temperature or high laser excitation power. The intermediately doped products can give white emission out of STE1 and STE2. The highly doping products give red emission out of STE2 (bipolaron states) at room temperature or low laser power. These interesting phenomena reflected the microscopic interactions between spins, carriers and phonons in the products, which can be found applications in the future fields of photonics and spintronics.
✓ 已验证
产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Yaru Han,Linpin Luo,Liang Zhang,Yi Kang,Hao Sun,Jie Dan,Jing Sun,Wentao Zhang,Tianli Yue,Jianlong Wang
Nanozymes have become a frontier of research recently and possess broad application prospects in the field of analytical sensing. Herein, a Fe–Mn bimetallic nanozyme (FeMnzyme) was proposed for colorimetric analysis of ascorbic acid (AA). The FeMnzyme, with high specific surface area, consisted of Fe–Mn mixed oxide amorphous core and α-FeOOH nanorod shell characterized by scanning electron microscope (SEM) and Powder X-ray diffraction (XRD). It exhibits typical oxidase-like properties to catalyze oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to generate visible blue oxidized TMB (oxTMB) without exogenous H 2 O 2 . Due to the reducibility of AA to oxTMB, the FeMnzyme/oxTMB system can be employed as a promising colorimetric sensor for quantitative analysis of AA. The method has a good linear concentration range of 8 μmol L −1 to 56 μmol L −1 , and the detection limit is as low as 0.88 μmol L −1 (3σ). Finally, the proposed biosensor has been favorably put into use to determine AA content in kiwi fruit, indicating its reliability for practical application.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Zhi Shen,Qiang Zhao,Hai-Quan Xie,Yu-Quan Feng,Shu-Yang Chen,Zhuo Shi
In this study, a multiple binding sites ligand, 5-(4-carboxyphenoxy)nicotinic acid ligand (H 2 cpna), was used to construct metal complexes with Zn 2+ , Cd 2+ , Mn 2+ and Co 2+ by solvothermal reaction, and four new complexes were constructed, namely, [Zn (cpna)•H2O]n (1)，[Cd (cpna) (CH 3 CN)·2H 2 O] n ( 2 ), [Mn (cpna)•2H 2 O] n ( 3 ) and Co(cpna)•2H 2 O] n ( 4 ); All the complexes were characterized by single crystal X-ray diffraction, elemental analysis and infrared analysis in the solid state; Single crystal x-ray diffraction analyses reveal that complexes 1 and 2 have two-dimensional network structures, complexes 3 and 4 have three-dimensional structures. In addition, Luminescence behavior of complex 1 and 2 was investigated and magnetic properties of complex 3 and 4 were studied. The fluorescent test results show that the fluorescence intensity of complex 1 is higher than that of ligand and emission band can be considered as LLCT emission of ligand; The Magnetic results indicate weak ferromagentic interactions in complex 3 and χ m T value rises slowly and then decreases sharply from 300 K to 2 K. However, magnetic results indicate antiferromagentic interactions in complex 4 and χ m T value can be divided into three parts with the change of temperature from 300 K to 2 K.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Xin Yu,Siran Xu,Xian Liu,Xiaohong Cheng,Yeshuang Du,Qi Wu
The development of self-supported nanosheet materials with porous multiple active sites has enormous potential for the application of oxygen evolution reaction (OER). Herein, we reported a three-dimensional (3D) porous nanosphere Mn-NiCo 2 S 4 /NF catalyst for OER. As a result, the simple Mn doping strategy results in good electrocatalytic performance and outstanding stability. During the OER, the Mn-NiCo 2 S 4 /NF only needs a small overpotential of 220 mV (40 mV lower than pure NiCo 2 S 4 /NF) to achieve the current density of 10 mA cm −2 , which is mainly due to a large number of exposed active sites and adequate pathways for mass diffusion and oxygen gas release. Moreover, Mn doping optimizes the electronic structure and thus facilitates electron transport , leading to superior electrocatalytic performance. The catalyst exhibits incredible corrosion resistance in 1 M KOH solution for 60 h or more. This work provides a valuable method to synthesize a low cost, high-efficiency, and corrosion resistant transition metal electrocatalyst for oxygen evolution using heteroatom doping strategy.
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 12
·4181-4195
·
IF 6.119
Fan Fu,Yufan Zhang,Yan Zhang,Yuyue Chen
In this experiment, Mn@TiO2 nanofibers in the form of membranes were fabricated by ordinary electrospinning and a higher temperature calcination process. Field-emission scanning, X-ray diffraction analysis, X-ray photoelectron spectroscopy, Raman spectra, UV-visible diffuse spectra, UV-visible spectroscopy, and Brunauer–Emmett–Teller (BET) evaluation were used to characterize the resulting samples. The study revealed that, upon the addition of the manganese ion, the continuous and mechanical properties of the nanofibers and nanofilms were substantially enhanced. Notably, after 60 minutes, the Mn@TiO2-0.10 degradation efficiency reached 94.92% under ultraviolet light, which was 5 times greater than that for TiO2 nanofibers. It was due to the controlled mixture phase and palpable raised specific surface area, which ensured a pronounced enhanced photocatalytic activity of the nanofibers. In addition, the application of nanofibers on the capacitor aspect was explored by electrochemical workstations. The highest photoactivity sample performed mass-specific capacity as high as 5.09 F g−1. Such efficient capacity and higher photoactivity of the photocatalyst shed light on the preparation of soft inorganic materials and their application in energy conversion.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Zhenxing Fang,Kuang Wu,Le Wang,Da Xu,Weiwei Wang,Yuhang Lin,Xiaohui Liu,Chun Sun
Mn doped two-dimensional (2D) layered perovskites , are becoming excellent candidates as red phosphor because of their high quantum yields (QY) and enhanced stability. However, these Mn doped 2D layered perovskites can only be excited by the near UV light , which largely limits the development of perovskites. Herein, blue-excitable Mn-doped PEA 2 (Pb/Mn)(Br/I) 4 PQDs are synthesized from anion exchange surface engineering strategy. After anion exchange, orange Mn 2+ emission from exciton-to-Mn energy transfer is acquired under the excitation of 450 nm. The PEA 2 (Pb/Mn)(Br/I) 4 compounds exhibit strong luminescence with photoluminescence (PL) QY of 52%, which is comparable to most of the reported red emitting phosphors. A prototype white light-emitting diode (WLED) with good optical performance was fabricated using commercial (Sr,Ba) 2 SiO 4 :Eu phosphor and as-prepared PEA 2 (Pb/Mn)(Br/I) 4 as green and orange color converters, showing great potential in the applications of solid state lighting.
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Han Qiao,Xiaoxiang Wang,Peng Liao,Cheng Zhang,Chongxuan Liu
A novel Mn(II) encapsulated mesoporous silica nanoparticles (Mn-MSNs) was developed for efficiently removing antibiotic tetracycline from aqueous solutions. The material has a well-ordered, hexagonal mesopore structure with a large specific surface area (720 m 2 /g) and maximum sorption capacity (229 mg/g) that is about an order of magnitude higher than that of mesoporous silica nanoparticles without Mn-encapsulated, or encapsulated with other transition metal cations Fe 3+ and Cu 2+ . Sorption results showed that the materials can sequestrate tetracycline within a large concentration range (5 μg/L–450 mg/L). Batch sorption experiment, spectroscopic analysis and density functional theory calculation collectively indicated that Mn–O complexation was the dominant mechanism for the tetracycline sorption. Electrostatic attraction and cation-π interaction also contributed to tetracycline sorption with their contribution levels varying with pH in a synergetic way with the Mn–O complexation. The Mn(II) encapsulated MSNs exhibited a good regeneration property over five repeated sorption-desorption cycles, demonstrating its promising potential in the cost-effective applications of sequestrating tetracycline from wastewater, drinking water , and contaminated solutions.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Zhiguo Zhang,Hua Huo,Zhenjiang Yu,Lizhi Xiang,Bingxing Xie,Chunyu Du,Jiajun Wang,Geping Yin
Mn doping is deemed as a promising strategy to improve the electrochemical performance of the α-Ni(OH) 2 battery-type supercapacitor electrode. However, the internal structure evolution, the pathways and the dynamics of the proton/intercalated anion migration, as well as the functioning mechanism of Mn dopant to stabilize the layered structure during cycles remain unclear. Here, we unveil that irreversible oxidization of Mn 3+ at the initial CV cycles, which will remain as Mn 4+ in the NiO 2 slabs after the first oxidization to effectively suppress the phase transformation from α-Ni(OH) 2 /γ-NiOOH to β-Ni(OH) 2 /β-NiOOH and further maintain the structural integrity of electrode. With a synergistic combination of theoretical calculations and various structural probes including XRD and 2 H MAS solid state NMR, we decode the structure evolution and dynamics in the initial CV (cyclic voltammetry) cycles, including the absorption/desorption of hydrogen containing species, migration of intercalated anions/water molecules and the change of interlayer space. This present work elucidates a close relationship between doping chemistry and structural reliability, paving a novel way of reengineering supercapacitor electrode materials.
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2020
·
IF 3.687
Anwei Wang,WeiYou Zhou,Zhonghua Sun,Zhong Zhang,Zhihui Zhang,MingYang He,Qun Chen
Developing efficient heterogeneous catalytic systems based on easily available materials and molecular oxygen for the selective oxidation of alkylarenes is highly desirable. In the present research, NiMn hydrotalcite (Ni 2 Mn-LDH) has been found as an efficient catalyst in the oxidation of alkylarenes using molecular oxygen as the sole oxidant without any additive. Impressive catalytic performance, excellent stability and recyclability, broad applicable scope and practical potential for the catalytic system have been observed. Mn 3+ species was proposed to be the efficient active site, and Ni 2+ played an important role in stabilizing the Mn 3+ species in the hydrotalcite structure. The kinetic study showed that the aerobic oxidation of diphenylmethane is a first-order reaction over Ni 2 Mn-LDH with the activation energy ( E a ) and pre-exponential factor ( A 0 ) being 85.7 kJ mol −1 and 1.8 × 10 9 min −1 , respectively. The Gibbs free energy (Δ G ≠ ) was determined to be -10.4 kJ mol -1 K -1 for the oxidation based on Eyring-Polanyi equation, indicating the reaction is exergonic. The mechanism study indicated that the reaction proceeded through both radical and carbocation intermediates. The two species were then trapped by molecular oxygen and H 2 O or hydroxyl species, respectively, to yield the corresponding products. The present research might provide information for constructing highly efficient and stable active site for the catalytic aerobic oxidation based on available and economic material.
✓ 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）