ENVIRONMENTAL POLLUTION
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2024
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IF 7.6
Kuang Wang,Zhanqiang Fang
In the homologous series of polybrominated diphenyl ethers (PBDEs), the debromination of low-brominated diphenyl ethers with higher toxicity remains a challenge. Nano zero-valent iron (nZVI) has been extensively studied for the debromination of PBDEs, but its inherent direct electron transfer mechanism is less efficient for low-brominated diphenyl ethers, and there are issues with high preparation costs. In this work, we synthesize Ni-doped oxalated submicron ZVI (Fe OX bm /Ni) using a low-cost ball-milling method. Fe OX bm /Ni exhibits a debromination rate constant of 0.48 day −1 for 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in tetrahydrofuran (THF)/water. The debromination rate of Fe OX bm /Ni for BDE-47 in water is even faster (0.98 day −1 ), with the yield of the complete debromination product, diphenyl ether, reaching 76.71%. In real groundwater, Fe OX bm /Ni also shows high reactivity toward BDE-47, with a rate constant of 0.33 day −1 . Kinetic experiments, quenching experiments, and degradation pathway indicate that the attack of atomic hydrogen on C-Br bonds is the primary degradation mechanism. Electrochemical analysis further show that Ni 0 sites could cleave hydrogen into absorbed atomic hydrogen (H∗ ABS ) and adsorbed atomic hydrogen (H∗ ADS ), with H∗ ADS playing the main role. These findings contribute valuable insights into advancing the large-scale application of ZVI and offer promising strategies for thorough remediation of PBDEs pollution.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
·
IF 12.2
Xu Yin,Jiatian Yu,Zhifeng Gao,Wei Li,Kajia Wei,Yun Jiang,Yonghao Zhang,Haoming Chen,Weiqing Han
Bromate (BrO 3 – ) is a common by-product of advanced oxidation water treatment processes. In this study, a catalyst combining MXene and Pd was synthesized to eliminate BrO 3 – by electrochemical reduction in flow-through mode. The fabricated Ti/Pd@MXene filter showed superior activity for BrO 3 – reduction compared with Ti/MXene filter. A satisfactory BrO 3 − removal performance by Ti/Pd@MXene filter was obtained at pH values of 5–7 with a current density of 1.0–2.5 mA·cm –2 . The mechanism explored by quenching experiments and EPR analysis demonstrated that atomic hydrogen (H*)-mediated reduction was dominant in the Ti/Pd@MXene filter system and contributed to 84.2 % of the BrO 3 − removal, which was greater than that of Ti (7.1 %) and Ti/MXene (43.9 %). DFT calculations revealed the introduction of Pd nanoparticles on MXene lowered the energy barrier for generating H* from OH* -H* , thus boosting H* formation. Furthermore, the Ti/Pd@MXene filter had favorable stability and applicability, and nearly 90 % of BrO 3 − could be eliminated in different water matrices. Moreover, energy consumption of the Ti/Pd@MXene filter was more competitive than that previously reported (0.348 kWh·mmol −1 ), especially for high BrO 3 − removal (≥75 %). This work highlighted an effective flow-through electrocatalytic filter to induce H* -mediated electrochemical reduction of BrO 3 − .
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
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2019
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IF 7.149
Huiling Liu,Jinglong Han,Jili Yuan,Chengbin Liu,Dong Wang,Tian Liu,Meijun Liu,Jinming Luo,Aijie Wang,John C. Crittenden
Efficient elimination of antibacterial activity of halogenated antibiotics by dehalogenation pretreatment is desired for a biochemical treatment process. In this study, crystalline cobalt phosphide nanosheet arrays on a Ti plate (C-CoP/Ti) are fabricated by a simple electrodeposition and phosphorization process. The crystalline structure greatly promotes atomic hydrogen (H*) generation. Moreover, the nanosheet arrays can provide abundant active sites and accelerate electron transfer and mass transport. As a result, the dehalogenation rate of florfenicol (FLO, an emerging organic pollutant) on C-CoP/Ti is 11.1, 2.97, and 13.6 times higher than that on amorphous CoP/Ti, Pd/Ti, and bare Ti, respectively. The C-CoP/Ti electrode achieves 97.4% dehalogenation of FLO (20 mg L–1) within 30 min at −1.2 V (vs Ag/AgCl). Nearly 100% of Cl and 20% of F are broken away within 120 min, showing the highest electrocatalytic defluorination efficiency reported so far. Both experimental results and theoretical calculations reveal that the dehalogenation of FLO on C-CoP/Ti is synergistically accomplished via direct reduction of electron transfer and indirect reduction of H*. This study develops a highly efficient non-noble metal electrode material for dehalogenation of halogenated organic compounds.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Xiaowen Zhang,Mengfan Niu,Kaiwei Zheng,Yang Liu,Yuankui Sun,Xiaohong Guan
Although nanoscale zero-valent iron (nZVI) has been widely used for nitrate reduction, its application is always limited by the undesired generation of toxic ammonium. In this study, by selecting four commonly used nZVI modification methods (i.e., introducing Fe(II), activated carbon, Cu, and Pd), the roles of direct electron transfer and atomic hydrogen (H*) mediated reaction on nitrate selective reduction were examined. Results revealed that all the modification methods could enhance the reduction rates of nitrate with a promotion factor of 0.94–8.62, while the N 2 -selectivity could only be increased from ∼4.5 % to less than 25.7 % (in carbon amended system). The enhancing effect of these additives is determined to be highly associated with their ability to promote the direct electron transfer from Fe 0 core to nitrate by forming galvanic couples or conductive magnetite layer. Unexpectedly, multiple lines of evidence suggested that H* was not the dominant reducing species responsible for nitrate reduction in Pd-modified nZVI system (and also the other tested systems), despite the presence of Pd could significantly accelerate H* generation. Correlation analysis further showed that there was no reasonable relationship between N 2 -selectivity and Fe 0 corrosion tendency and hydrogen formation rates of different modified nZVI systems. All these finding could improve our understanding of nitrate selective reduction by Fe 0 .
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
·
IF 8.355
Zimo Lou,Jiang Xu,Jiasheng Zhou,Kunlun Yang,Zhen Cao,Yizhou Li,Yuanli Liu,Liping Lou,Xinhua Xu
Atomic H* has been regarded as the key active species for the electrocatalytic hydrodechlorination (ECH), and the electrode design and operation conditions are related to the atomic H* generation. However, there is limited understanding of how the operation parameters affect the atomic H* generation and utilization. Due to the fact that Pd was inefficient in water dissociation step, MnO 2 was combined with Pd to construct a novel Pd/MnO 2 /Ni foam cathode. Cyclic voltammetry confirmed that Pd/MnO 2 /Ni foam cathode with MnO 2 load of 0.51 mg cm −2 possessed the highest atomic H* generation and ECH activity. Excessive Pd load (>0.44 mg cm −2 ) was detrimental to ECH because of the side hydrogen evolution reaction (HER). Operation conditions (e.g. applied current and electrolyte concentration) would directly affect the cathode potential, which was an important indicator of the atomic H* generation. The optimal cathode potential was determined to be −0.85 V when the applied current was 10 mA in this study. The electrolyte concentration of 10–15 mM was able to provide sufficient atomic H* for ECH, while excessive input of electrolyte would favor HER but inhibit ECH. ECH at acidic and neutral/alkaline solution underwent different pathways for atomic H* generation and further affect the utilization of atomic H*. After 120 min reaction, >70% of atomic H* could be selectively used for ECH at initial pH of 4.0 and 5.0, while only ∼37% was used for ECH at initial pH of 7.0. This work correlated the reactivity of electrode with the atomic H* and cathode potential, which would provide strategies for ECH catalyst design and operation optimization.
研究领域:
环境科学
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电化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Fangxian Wang,Junwei Yang,Shihao Li,Junwen Liang,Yuwei Wang,Rong Du,Bo Zhou,Qiong Liu,Changping Li
Bromate is a commonly identified carcinogenic and genotoxic disinfection byproduct in water. Electrochemical debromination is an environmentally friendly and effective approach but it often suffers the limited reducing atomic H (H*) ability and high metal catalyst dosage. In this study, a unique composite catalyst comprised of ultra-low loading Cu single atoms (0.016 wt%) and Fe 2 O 3 nanoparticles supported on a Nb 2 C MXene (denoted as Cu 0.2 /Fe 0.1 /Nb 2 C) was synthesized by one-step high-temperature molten salt method. The Cu 0.2 /Fe 0.1 /Nb 2 C significantly outperformed the Nb 2 C, Cu 0.2 /Nb 2 C and Fe 0.1 /Nb 2 C counterparts in the electrochemical debromination with a 94.2 % removal efficiency of bromate. It is revealed that the introducing of Cu single atoms, efficiently promotes the adsorption of H* and inhibition of competitive H 2 evolution. The incorporation of Fe 2 O 3 nanoparticles significantly increased the electronic metal-support interaction effect between the metal components and Nb 2 C, thereby forming a noticeable electronic cloud bridge to facilitate efficient charge transfer. Ultimately, the synergistic interplay between Cu single atoms and Fe 2 O 3 nanoparticles plays a crucial role in achieving the remarkable removal performance of bromate. This work not only presents a significant instance of a synergistic catalyst involving metal single atoms and metal nanoparticles for effective electrochemical debromination but also advances the understanding of the electronic metal-support interaction.
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
JOURNAL OF HAZARDOUS MATERIALS
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2024
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IF 12.2
Ge Song,Huizhong Wu,Xuechun Wang,Shuaishuai Li,Ruiheng Liang,Minghua Zhou
Electrocatalytic dechlorination by atomic hydrogen (H*) is efficient, but limited by the low efficiency of H* production. Herein, a phosphorus-doped cobalt nitrogen carbon catalyst (Co-NP/C) was prepared, which had high catalytic activity in a wide pH range (3−11). The turnover frequency of Co-NP/C (3.54 min −1 ) was 1.21–59000 times superior to that of current Pd-based and non-noble metal catalysts (0.00006–2.92 min −1 ). Co-NP/C significantly enhanced H* generation, which was 1.52, 2.44, and 3.77 times stronger than that of Co-N/C, NP/C, and N/C, respectively, since the introduction of phosphorus was found enhanced the electron density of cobalt and regulated the electron transfer . Co-NP/C showed outstanding catalytic performance after ten cycles and could achieve nearly complete chloramphenicol removal. This regulation method was verified to be effective for other non-noble metal (Fe, Mn, Cu, Ni) phosphorus doped catalysts, proposing a general class for efficient electrochemical dechlorination, which would be of great significance for the elimination of chlorinated organic pollutants .
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2021
·
IF 11.236
Jia Deng,Enlai Gao,Feng Wu,Zhixiong You,Xiaozhong Li,Shuxian Gao,Li-Zhi Huang
Atomic hydrogen (H•) is highly reactive for the hydrodechlorination of trichloroethylene (TCE). In this work, we found that the coprecipitation of Ni 2+ and Fe 2+ at neutral pH led to an unprecedented catalytic generation of H•. The generated H• effectively dechlorinate TCE to nontoxic ethylene and ethane, and Fe 2+ is the only electron donor. The abundant adsorbed H• produced with a Ni/Fe ratio of 0.4 enhances hydrogen evolution reaction causing a low efficiency for hydrodechlorination. In contrast, the active absorbed H• is generated in the crystal lattice of Ni-Fe hydroxides with a Ni/Fe ratio of 3.0 causing highly efficient hydrodechlorination of TCE. This work not only reveals the mechanism of catalytic hydrodechlorination by Ni-Fe hydroxides at neutral pH, but also provides a novel approach to detoxify TCE in contaminated water using facile precipitated Ni-Fe hydroxides.
研究领域:
环境科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2021
·
IF 9.028
Jun Zhang,Gong Zhang,Huachun Lan,Jiuhui Qu,Huijuan Liu
For effective treatment and reuse of wastewater, removal of organochlorines is an important consideration. Oxidation or reduction of these compounds by one-component free radicals is difficult because of the high-energy barrier. Theoretical calculations predict that redox synergy can significantly lower the energy barriers. Hence, we developed an energy-efficient dual photoelectrode photoelectrochemical system wherein the oxidized and reduced radicals coexist. Taking p-chloroaniline as an example, the atomic hydrogen first initiates nucleophilic hydrodechlorination to form a critical intermediate followed by the electrophilic oxidation of the hydroxyl radical; the process shows stable free-energy changes. Compared to oxidation alone, the reaction rate and mineralization in the redox synergy system were ∼4.5 and ∼2.1 times higher, respectively. Nitrogen was also completely removed via this system. The full life cycle assessment with power consumption as the boundary showed that the proposed system was sustainable and highly energy efficient, ensuring its application in organochlorine wastewater treatment.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Haoyang Huang,Yanxiao Si,Jiajun Zou,Jiawei Li,Yongjie Li,Wenxin Huo,Haichuan Zhang,Yingjie Li,Ji Li
The H*-mediated electro-Fenton system, a novel byproduct-free H 2 O 2 activation technology, faces economic and universality challenges. This study fabricated a non-noble nickel-based catalyst to replace palladium (Pd), constructing a sandwich-structured NiO/oxidized carbon black electrode (SE-NiO/OCB) enriched with three-phase interfaces (TPI) for tetracycline (TC) removal. SE-NiO/OCB demonstrated efficient catalysis of atomic H* generation, achieving a significantly higher ·OH exposure of 19.18 × 10 −12 M·s compared to SE-OCB (5.37 × 10 −12 M·s). Additionally, the SE-NiO/OCB exhibited a remarkable TC removal efficiency of 96.7 % within 90 min, far exceeding SE-OCB (55.9 %). By leveraging H + /H 2 O as H* sources, the SE-NiO/OCB maintained ≥ 83.4 % TC removal across a broad pH range of 3–11, validating exceptional pH adaptability. Additionally, SE-NiO/OCB achieved a removal rate of ≥ 86.7 % for multiple tetracycline antibiotics at neutral pH, underscoring its broad applicability. The cost of utilizing SE-NiO/OCB to drive the H*-mediated E-Fenton reaction for TC removal was merely 0.05 RMB/(mg TC), which was significantly lower than that of noble metal catalysts. Thus, this work resolved critical economic and universality limitations in H*-mediated electro-Fenton processes, advancing scalable antibiotic wastewater treatment strategies.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Zhichao Ma,Chenyi Wang,Tianfang Yang,Gangya Wei,Jinrui Huang,Mengran Liu,Kun Zhang,Zunjie Zhang,Yang Liu,Shuyan Gao
Electrocatalytic nitrate (NO3−) reduction to ammonia (NH3) (NRA) is of great significance for solving the problem of urgent NO3− pollution in the environment and opening up a new route to synthesize NH3. However, NRA is limited by its multi-electron/proton transfer process and the NRA process relies heavily on atomic H* produced by H2O splitting, undergirding the necessity for effective NRA catalysts. Herein, three-dimensional (3D) porous phosphorus (P)-doped Cu–Ni alloy materials are constructed through a one-step electrodeposition synthesis. 3D porous materials modulate hydrophilicity and enrich active sites. The Cu d-band center can be tuned through Ni alloying to modify the adsorption energies of intermediates such as *NO3−, *NO2−, and *NH2. The hydrogenation evolution capacity of P promotes the hydrogenation process in the atomic H* path and effectively accelerates the NRA reaction rate. Density functional theory (DFT) calculations demonstrate that the charge transfer between the negatively charged Pδ− and the positively charged Niδ+ and Cuδ+ assists in generating more atomic H* for coupling with reaction intermediates, showing an enhanced catalytic activity at low overpotential. The optimal sample exhibits an exceptional NRA performance with an ammonia yield rate of 848.1 μmol h−1 cm−2 and a faradaic efficiency of 96.1%. This work provides a strategy for creating effective NRA catalysts through enhancing the atomic H* reduction strategy.
研究领域:
环境科学
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材料科学
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电催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Chuyan Deng,Yujun Zhou,Xin Cai,Jiamin Gao,Junwen Qi,Zhigao Zhu,Yue Yang,Jiansheng Li
Atomic hydrogen (H*)-mediated indirect electrochemical reduction has regarded as a highly effective strategy for halogenated organic pollutants (HOPs) removal in wastewater. The efficient generation and prompt utilization of H* are critical factors which directly determine the degradation performance. This study presented a new strategy for the electro-reduction of a typical HOP—2,4,6-trichlorophenol (2,4,6-TCP), achieved by modulating the electronic structure of a PdCo bimetal electrode (Pd 1 Co 1 /CP). Through characterizations and density functional theory (DFT) analysis, ZIF-67 as the Co source could effectively improve the uniform distribution of Pd and Co, which exposed more active sites for H* on-demand generation. Meanwhile, the introduction of Co atoms and the optimum of Pd/Co ratios modulated the electronic structure of Pd sites. In 120 min, 92 % 2,4,6-TCP (initial concentration 10 mg/L) was degradated with a reaction rate constant (k obs ) of 0.103 min −1 , which was 2.1 times higher than that of Pd/CP electrode. Lower Gibbs free energy for hydrogen adsorption (−0.477 eV) was found in Pd 1 Co 1 /CP which benefited the surface-adsorbed H* stability for enhanced utilization. The degradation pathway of 2,4,6-TCP was further studied. These findings highlight the critical role of modulating the electronic structure of the electrode to optimize the utilization of surface-adsorbed active intermediates, presenting a novel and promising approach for advancing wastewater treatment technologies.
研究领域:
环境科学
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材料科学
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理论化学
✓ 已验证
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）