INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Wenyu Dong,Qizhao Pan,Zhaoshun Liu,Hongbin Sun,Zhongning Shi,Junli Xu
High-entropy materials has achieved much attention in the recent decade years. However, there is few reports on high-entropy MOFs due to the large difference of coordination ability for different metal ions . In this work, high-entropy ZIFs are successfully electrodeposited on the nickel foam substrate under high overpotential, and the effects of potential, electrodeposition time and metal precursor concentration on the morphologies and catalytic activity of deposits are examined. The results indicate that the prepared HE-ZIF is made of nanoparticles with a low crystalline structure, and it shows a high electrocatalytic activities for oxygen evolution reaction (OER) as it possesses an abundance of defects such as vacancy defects , lattice distortions and amorphous structure. The overpotential at the current density of 100 mA cm −2 is 290 mV with good durability in 100 h continuous test for OER in 1 mol L −1 KOH.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 74
·70547-70552
·
IF 3.289
Qiu-Yun Chen,Dong-liang Huang,Yin-Bing Wang,Jian Shao,Ling-Ling Qu
The development of dye-loaded nanosorbcats can make best use of their advantages in removing dyes from wastewater, also bypassing their disadvantages. Herein, functionalized Fe2O3 nano-rods (pfa@Fe2O3) were synthesized by using tween-80 induced assembly of pyrrol-2-methanoic acid (pfa) and iron(III) salts, and characterized by FT-IR, XRD, EPR, and SEM. The pfa@Fe2O3 nanorods’ adsorption capacity for methylene blue (MB) was 450 mg g−1 compared to only 39 mg g−1 for α-Fe2O3. Moreover, the kinetics to reach equilibrium were approximately 0.5 h and the pfa@Fe2O3 nanorods can be used as efficient recyclable adsorbents for MB. In particular, the MB loaded MB@pfa@Fe2O3–water system could also be used as dioxygen generator when irradiated with red LED light (10 W). The light induced intramolecular charge transfer between catalysts and photosensitizers was more efficient in the MB@pfa@Fe2O3/H2O system, and it exerted higher activity for water oxidation than the traditional catalyst/Ru(bpy)32+ system. Control experiment results suggested that the α-Fe2O3 can’t be used as LED light driven catalysts for water oxidation. In conclusion, the MB@pfa@Fe2O3 nanorods were efficient recyclable nanosorbcats for LED-light-driven dioxygen generation using water as oxygen source.
研究领域:
材料科学
·
环境科学
·
光化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Jinyan Du,Xiaohui Zhong,Huichao He,Ji Huang,Minji Yang,Gaili Ke,Jun Wang,Yong Zhou,Faqin Dong,Qin Ren,Liang Bian
Manipulation of interfacial charge separation and transfer is one of the primary breakthroughs to improve the water oxidation activity and stability of BiVO4 photoanode. In the present work, a CoMoO4-coupled BiVO4 (BiVO4/CoMoO4) film was designed and prepared as the photoanode for photoelectrochemical (PEC) water oxidation. Compared with the bare BiVO4 film, obviously improved PEC water oxidation performance was observed on the BiVO4/CoMoO4 film. Specifically, a higher water oxidation photocurrent density of 3.04 mA/cm2 at 1.23 V versus RHE was achieved on the BiVO4/CoMoO4 photoanode, which is of about 220% improvement over bare BiVO4 photoanode (1.34 mA/cm2 at 1.23 V vs RHE). In addition, the BiVO4/CoMoO4 film photoanode was of better stability and faster hole-to-oxygen kinetics for water oxidation, without significant activity attenuation for 6 h of reaction at 0.65 V versus RHE. The enhanced water oxidation performance on the BiVO4/CoMoO4 film photoanode can be ascribed to the synergistic effect of the following factors: (i) thermodynamically, the photogenerated holes of BiVO4 are directionally transferred to CoMoO4 through their physical coupling interface and valance band potential matching; and (ii) kinetically, the transferred holes induce the formation of Co3+-active sites on CoMoO4 that could synergistically oxidize H2O to molecular O2 with stable activity.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 45
·455405
·
IF 3.551
Xiaolin He,Chaoqun Shang,Qingguo Meng,Zhihong Chen,Mingliang Jin,Lingling Shui,Yongguang Zhang,Zhang Zhang,Mingzhe Yuan,Xin Wang,Krzysztof Kempa,Guofu Zhou
Hematite is recognized as an excellent photocatalyst for photoelectrochemical photoanodes for water oxidation because of its favorable band gap, excellent anti-photocorrosion and structural stability in alkaline solution. However, slow charge transport and fast carrier recombination in the bulk and at the hematite photoanode/electrolyte interface, have limited its applications for water splitting. Herein, we report a highly efficient hematite/ferrhydrite (Fh) core–shell photoanode system, consisting of hematite (α-Fe2O3) semiconductor nanorods which dramatically enhance light harvesting, and ferrhydrite as the hole-storage shell. Our integrated hematite/ferrhydrite core–shell photoanode shows 2.7 times increased photo-current density under simulated sun light irradiation.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Materials Today Energy
·
2020
·
IF 5.604
H.A. Younus,M. Vandichel,N. Ahmad,E. Ahlberg,M. Busch,F. Verpoort
Water oxidation is traditionally performed over IrO 2 and RuO 2 owing to their high stability at low pH compared to molecular O 2 evolution catalysts. The low stability of molecular complexes in acids limits their industrial exploitation as anodes in water-splitting devices, where high current densities and proton conductivity are required. Herein, an existing Co(1,10-phenanthroline) 2 complex film is engineered to improve its pH-stability via extra OH substituents on the ligand, i.e. 1,10-phenanthroline-4,7-diol. This novel Co(1,10-phenanthroline-4,7-diol) 2 complex film is active for water oxidation at low overpotentials and stable at low pH. Since the calculated water oxidation overpotentials of both complexes are similar, the difference in water oxidation activity is attributed to a smaller charge transfer resistance, which originates from a different anchoring style to the electrode via the OH groups of the ligand. This result is supported by electrochemical impedance measurements. The high pH-stability of the Co(1,10-phenanthroline-4,7-diol) 2 film is computationally rationalized by a high crystal formation energy observed in DFT calculations. In summary, an acid-stable and active cobalt-based metal-organic film is reported that competes well with most reported earth-abundant catalysts for water oxidation under similar conditions.
研究领域:
化学
·
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Yuanyuan Qian,Furui Tan,Jun Liu,Qicong Li,Kuankuan Ren,Yanbin Huang,Xiaobao Li,Dawei Cao,Kong Liu,Chao Zhao,Yongxin Li,Zhijie Wang,Shengchun Qu
Plasmon-induced photocatalytic reactions are important in the process of conversion of solar energy into fuels. To efficiently harvest energetic charge carriers from light-excited plasmonic materials, contact of the metallic nanostructures with semiconductors is necessary. Herein, we report that, even on single Au nanowires that are not in contact with any semiconductors, prominent photocatalytic water oxidation reactions could be still observed. The involved Au nanowires have dimensions of 300 nm in diameter, and the fabricated nanoelectrode presents an obvious photocurrent of 0.4 mA/cm2 at the potential of 1.2 V vs Ag/AgCl. The corresponding incident photon-to-electron conversion efficiency is realized as 0.24% at the wavelength of 520 nm. Detailed investigations reveal that the hot holes around the d-band of the plasmonic nanomaterials are responsible for such photocatalytic behaviors. Our results provide a special perspective to the plasmon-related reactions.
研究领域:
材料科学
·
能源转换
·
纳米技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yang Liu,Xinyu Sun,Ying Wang,Shiqing Zhang,Fang Liu,Shaokai Ma,Jun Zhang,Ying Li,Yanming Xue,Chengchun Tang
Birnessite (δ-MnO 2 ), inspired by biological photosynthesis, holds promise as oxygen evolution reaction (OER) catalysts in water electrolysis for clean energy. Given that Mn 3+ serves as the active sites, various strategies have been employed to increase the Mn 3+ content to boost the OER activity. To surpass the limitations of the traditional adsorbate evolution mechanism (AEM), we have adopted an electrochemical reduction method to introduce metallic Ni and enrich oxygen vacancies onto δ-MnO 2 nanosheets. The resulting Ni/MnO 2 v /CC exhibits exceptional OER performance, with a reduction in overpotential by 190 mV (from 478 mV to 289 mV) at 10 mA cm −2 and a Tafel slope as low as 45 mV dec -1 , indicating accelerated catalytic activity. Experimental and theoretical analyses attribute this enhancement to a transition from the traditional AEM to lattice oxygen mechanism (LOM) mechanism. Moreover, the dual modification also enhances electronic conductivity, electrochemical surface area, and charge transfer ability of δ-MnO 2 . Our work offers a pathway to overcome conventional limitations in OER electrocatalysts, applicable not only to Mn-based catalysts but also to a range of other transition metal oxides.
研究领域:
能源材料
·
电化学
·
纳米科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2018
·Vol. 8
·期 12
·983
·
IF 3.504
Shiman He,Yuying Meng,Yangfei Cao,Senchuan Huang,Jingling Yang,Shengfu Tong,Mingmei Wu
TiO2is one of the most attractive semiconductors for use as a photoanode for photoelectrochemical (PEC) water oxidation. However, the large-scale application of TiO2photoanodes is restricted due to a short hole diffusion length and low electron mobility, which can be addressed by metal doping and surface decorating. In this paper we report the successful synthesis of hierarchical Ta doped TiO2nanorod arrays, with nanoparticles on the top (Ta:TiO2), on F-doped tin oxide (FTO) glass by a hydrothermal method, and its application as photoanodes for photoelectrochemical water oxidation. It has been found that the incorporation of Ta5+in the TiO2lattice can decrease the diameter of surface TiO2nanoparticles. Ta:TiO2-140, obtained with a moderate Ta concentration, yields a photocurrent of ∼1.36 mA cm−2at 1.23 V vs. a reversible hydrogen electrode (RHE) under FTO side illumination. The large photocurrent is attributed to the large interface area of the surface TiO2nanoparticles and the good electron conductivity due to Ta doping. Besides, the electron trap-free model illustrates that Ta:TiO2affords higher transport speed and lower electron resistance when under FTO side illumination.Keywords:hierarchical TiO2;Ta doping;charge separation;photoelectrochemical water oxidation
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Haili Tong,Yi Jiang,Qian Zhang,Wenchao Jiang,Kaili Wang,Xiaoxi Luo,Ze Lin,Lixin Xia
Modification of the semiconductor surface by cobalt-rich catalysts is an effective strategy to improve the photoelectrochemical (PEC) water oxidation kinetics and migration of photogenerated electron and hole. In this study, cobalt phosphide (CoP) nanosheet was integrated on the nanoporous bismuth vanadate (BiVO4) electrode by using the hydrothermal method. The introduction of CoP significantly improved the PEC performance of the photoanode, with a photocurrent up to 4.0 mA cm–2 at 1.23 V (versus RHE) under simulated 100 mW cm–2 irradiation, a 3-fold enhancement over that obtained by the bare BiVO4. The BiVO4+CoP photoanode exhibited an impressive early onset of water oxidation, with a more than 220 mV cathodic shift of the onset potential, superior to the typical Co3O4 and Co–Pi cocatalysts-modified BiVO4 photoanode. Systematic studies show that the improvement in PEC performance by CoP is mainly due to the restraint of surface charge recombination and increase in photovoltage.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2019
·Vol. 102
·期 10
·6194-6201
·
IF 3.094
Shunhang Wei,Shu Jin,Guoxiang Pan,Zuxin Li,Gang Liu,Xiaoxiang Xu
Although BaNbO 2 N has visible light absorption as far as 740 nm, its photocatalytic activity is generally very poor under ordinary conditions, being incommensurate to its light absorption properties. In this work, we introduce Ca into the B site of BaNbO 2 N to form a complex perovskite BaNb 1− x /3 Ca x /3 O 2+ y N 1− y (0 ≤ x , y ≤ 1). The presence of Ca in BaNbO 2 N has great impact on a number of important properties such as band gap value, nitrogen content, surface hydrophilicity, and defects levels. In particular, defects such as Nb 4+ species are effectively suppressed in Ca-modified BaNbO 2 N. More importantly, photocatalytic activity of BaNbO 2 N for water oxidation reactions is substantially improved after Ca modifications. Compared with pristine BaNbO 2 N, more than twofold enhancement in photocatalytic oxygen evolution is observed for BaNb 0.8 Ca 0.2 O 2+ y N 1− y ( x = 0.6). Such improvements probably stem from the suppression of Nb 4+ species in the structure as well as enhanced surface hydrophilicity after Ca modification. The facile approach by incorporating alkaline earth cations into crystal structure can be well extended to other perovskite oxynitrides whose photocatalytic activity is subject to those defective species.
研究领域:
材料科学
·
光催化化学
✓ 已验证
产品关联
DOI
高影响因子
ChemCatChem
·
2016
·Vol. 8
·期 12
·2165-2170
·
IF 4.724
Cui Lu,Jianying Wang,Zuofeng Chen
Graphical Cu-based water oxidation catalysts : A self-assembling Cu II –4 Gly complex is reported as a catalyst precursor for water oxidation. Electrolysis with this complex precursor results in in situ formation of a surface-accumulated copper(II) deposit, dominated by an amorphous, phosphate-incorporated CuO/Cu(OH) 2 mixture. An onset overpotential of 380 mV and a current density of 1 mA cm −2 could be achieved at an overpotential of 450 mV with a Tafel slope of 64 mV dec −1 . Although notable progress has been made in developing first-row transition-metals-based water oxidation catalysts, continuous efforts are required to identify more inexpensive, efficient, and robust catalysts. Here, we demonstrate the utility of a series of readily available complexes formed by earth-abundant copper and amino acids as catalyst precursors. In phosphate solution at pH 12, electrolysis with 1 m m Cu II and 4 m m Gly results in in situ formation of an amorphous surface precipitate of a CuO/Cu(OH) 2 mixture, which incorporates a substantial amount of phosphate anions. This surface-bound solid can catalyze water oxidation with an impressive onset overpotential of 380 mV, an overpotential of 450 mV for a current density of 1 mA cm −2 , and a low Tafel slope of 64 mV dec −1 , which make it among the most active Cu-based heterogeneous electrocatalysts. The copper-based reactivity toward water oxidation is shared by Cu II complexation to other amino acids as catalyst precursors.
研究领域:
电化学
·
催化科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·
IF 13.3
Shuyang Peng,Di Liu,Keyu An,Zhiqin Ying,Mingpeng Chen,Jinxian Feng,Kin Ho Lo,Hui Pan
Green hydrogen is considered to be the key for solving the emerging energy and environmental issues. The photoelectrochemical (PEC) process for the production of green hydrogen has been widely investigated because solar power is clean and renewable. However, mass production in this way is still far away from reality. Here, a Si photoanode is reported with CoO x as co-catalyst for efficient water oxidation. It is found that a high photovoltage of 350 mV can be achieved in 1.0 m K 3 BO 3 . Importantly, the photovoltage can be further increased to 650 mV and the fill factor of 0.62 is obtained in 1.0 m K 3 BO 3 by incorporating Mo into CoO x . The Mo-incorporated photoanode is also highly stable. It is shown that the incorporation of Mo can reduce the particle size of co-catalyst on the Si surface, improve the particle-distribution uniformity, and increase the density of particles, which can effectively enhance the light absorption and the electrochemical active surface area. Importantly, the Mo-incorporation results in high energy barrier in the heterojunction. All of these factors are attributed to improved the PEC performance. These findings may provide new strategies to maximize the solar-to-fuel efficiency by tuning the co-catalysts on the Si surface.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子