JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2020
·
IF 5.647
Shuo Li,Jia Liu,Tianwei Tan,Jiapei Nie,Huili Zhang
To reduce the emission of greenhouse gases, the substitution of fossil fuel by renewable energy sources is increasingly important. Matching energy supply and demand is however required, even more so if intermittent renewable energy sources are employed. Thermal energy storage then offers significant advantages. Thermo-chemical energy storage systems, using reversible reactions, have a high reaction enthalpy that exceeds the storage capacities of sensible and latent heat modes. Magnesium hydroxide is a candidate TCES material for such a system at temperature around 300 °C, and adaptable when doping Mg(OH) 2 with metal salts. Both pure Mg(OH) 2 and its composites with 1, 3, 6 and 10 wt% LiNO 3 are studied. The present work validates this TCES process and develops reaction rate equations needed for its design. The LiNO 3- doping significantly reduces the onset temperature of dehydration. For pure Mg(OH) 2 , the temperature is 325 °C. It is reduced to 289 °C when 1 wt% LiNO 3 is present, and further reduced to 269 °C at a dosage of 10 wt% LiNO 3 . Whereas the dehydration of pure Mg(OH) 2 is slow, with a rate constant k of 1.72 10 −5 s −1 at 300 °C, adding increasing amounts of LiNO 3 progressively increases the reaction rate constant to ~10 −2 s −1 at 300 °C when 10 wt% LiNO 3 is present. The kinetic expressions enable to predict the conversion yield and amount of heat stored or released for any desired temperature and selected duration of the heat-induced dehydration. LiNO 3- doped Mg(OH) 2 have a high potential in TCES applications when the heat source is available at temperatures between 250 and 400 °C, since the equilibrium temperature and the extent of de-hydration Mg(OH) 2 can be tuned to the required temperature range by adding different wt% of LiNO 3 .
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Bin Yan,Ji Lan,Yueshan Li,Yinjie Peng,Lingying Shi,Rong Ran
In this paper, hexagonal Ni(OH) 2 nanosheets were prepared by hydrothermal method with nickel chloride hexahydrate as matrix and ammonia as precipitant. The lateral size of Ni(OH) 2 nanosheets was about 100–250 nm. The structure of the Ni(OH) 2 sheets was characterized by XRD , SEM , IR, TGA etc. Pickering emulsion was prepared by using Ni(OH) 2 nanosheets as stabilizer and dichloromethane (DCM) as oil phase. Furthermore, the stability factors of Pickering emulsion and the adsorption of Congo red (CR) on interface particle layer were studied. The adsorption equilibrium of CR was analyzed by Langmuir adsorption model and Freundlich adsorption model, and the adsorption process was researched by pseudo-first-order kinetics and pseudo-second-order kinetics. Compared with Ni(OH) 2 in the water phase, the Ni(OH) 2 in interface particle layer exhibited a much higher adsorption capacity and a faster deposition rate . The adsorption mechanism of CR can be mainly attributed to electrostatic interaction between the positively charged interface particle layer and the anionic CR molecules. It can be expected that as a promising adsorbent for CR removal in water treatment, the Ni(OH) 2 sheets in Pickering interface layer can provide a new strategy for dye adsorption.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Xianshu Qiao,Hongjun Kang,Yang Li,Kai Cui,Xin Jia,Henghao Liu,Wei Qin,Max Pupucevski,Gang Wu
We report a highly efficient and stable electrode composed of a porous Fe-doped β-nickel hydroxide nanopyramid array supported on nickel foam (U–Fe-β-Ni(OH)2/NF) for overall water splitting. The unique structure is assembled via a self-templated strategy by utilizing the FeNi oxalate (FeNi–C2O4/NF) nanopyramid as the templates, followed by an anion-exchange reaction at room temperature. Due to the intrinsic activity of Fe-doped β-Ni(OH)2 along with unique porous array structures consisting of two-dimensional (2D) active materials on three-dimensional (3D) conductive substrates, the developed electrode exhibited outstanding electrocatalytic activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in an alkaline medium. The introduced amount of Fe plays a significant role in promoting OER and HER activity compared to the β-Ni(OH)2 electrode. The optimal electrode (U–Fe-β-Ni(OH)2/NF-2) generated a current density of 10 mA cm–2 at low overpotentials of 218 mV for the OER and 121 mV for the HER. The electrode also demonstrated considerably stable performance during the continuous water splitting process. Furthermore, we elucidated the promotion mechanisms of the active Fe-doped β-Ni(OH)2 compound for the OER and HER based on extensive characterization and electrochemical measurements. Hence, this work provides a facile approach to developing low-cost, efficient, and stable hydroxide-based electrodes for bifunctional OER and HER in water splitting.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2026
·
IF 8.4
Qian-Yu Wang,Sian-Hong Ong,Zi-Ye Liu,Zhong-Wei Zhang,Quan-De Li,Ji-Ming Hu
Conductive graphene nanosheets boost oxygen evolution electrocatalysis. • Electrochemically assisted deposition forms porous Ni(OH) 2 /NiO onto freestanding graphene. • Low overpotential of 260 mV at 10 mA cm −2 and Tafel slope of 41 mV dec −1 . • Macroscopic model indicates faster *OOH formation with transfer coefficient of 0.74 Developing low-cost oxygen evolution reaction (OER) catalysts with efficient charge transport and accessible active sites is essential for alkaline water electrolysis. Here we report an electrochemically assisted technique (EAT) to deposit highly dispersed Ni(OH) 2 species on the surface of freestanding graphene (Gr) without deliberate surface functionalization, where a transient SiO 2 -derived framework assists the deposition process of Ni(OH) 2 , followed by heat treatment and alkaline etching to form an intimately contacted Gr@eNi(OH) 2 -NiO composite. On one hand, Gr enables the highly dispersed distribution of Ni(OH) 2 /NiO species and improves the accessibility of active sites for the OER. On the other hand, Gr provides good electrical conductivity and rapid charge-transfer kinetic, leading to high catalytic activity. In 1 M KOH, Gr@eNi(OH) 2 -NiO delivers an overpotential of 260 mV at 10 mA cm −2 and Tafel slope of 41 mV dec −1 , together with stable operation in alkaline electrolyte. Macroscopic kinetics analysis based on current-overpotential fitting further suggests an enhanced potential response of the *OOH-forming step, consistent with improved OER kinetics enabled by Gr-deposit coupling. This work provides a practical route to integrate Ni hydroxide/oxide phases with Gr scaffolds for efficient alkaline water oxidation. Download: Download high-res image (334KB) Download: Download full-size image
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 12
·3568-3578
·
IF 5
Menghui Liu,Chenhui Wang,Zifan Cao,Aiqun Kong,Yusheng Gao,Jinli Zhang,You Han,Wei Li,Yan Fu
A series of 3D self-standing PtRu/Ni(OH)2/NF electrodes is fabricated for electrocatalytic hydrogenation (ECH) of benzoic acid (BA) to cyclohexanecarboxylic acid (CCA). The PtRu/Ni(OH)2 electrocatalyst with a unique coral-shaped architecture possesses outstanding charge transfer ability and abundant active sites. The optimized electrode achieves a BA conversion of 99.00% and a CCA selectivity of 100% in 0.05 M H2SO4 within 80 min, showing a record faradaic efficiency of 43.90% and high performance during 20 cycles of ECH. In situ Raman tests verify the mechanism of the selective hydrogenation of the aromatic ring and density functional theory (DFT) calculations reveal that the electronic interaction between Pt and Ru in the PtRu nanoalloy as well as the electron transfer from the PtRu alloy to the Ni(OH)2 nanosheet tunes the electronic states of PtRu/Ni(OH)2, thereby enhancing the adsorption strength of BA on the electrocatalyst surface. This work offers a promising alternative to the traditional catalytic hydrogenation of BA.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 15
·7305-7311
·
IF 3.3
Jie Liu,Yu Chen,Yin Wang,Lu Liu,Qi Chen,Qingqing Shi,Luyi Huang,Xing Chen,Kun Xie
Cobalt phosphide has excellent electrical conductivity, metallic properties, and thermal stability. However, its application is limited due to the few active sites exposed in electrochemical reactions and poor structural stability. Herein, we adopt the strategies of material compounding and structural design to construct CoP@Ni(OH)2 bilayer nanosheets. The bilayer nanosheet structure can provide abundant transport paths for electrons and ions while also exposing more electroactive sites. In addition, the close contact and mutual support of the bilayer nanosheet structure can significantly alleviate material morphological collapse during charging/discharging processes, improving the cycle stability. The advantages of multiple components were combined in CoP@Ni(OH)2 to provide multiple valances for the faradaic redox reactions. The CoP@Ni(OH)2 manifested a specific capacity of 1697.8 C g−1 at 1 A g−1 and maintained a high rate capability of 35.0% even at 20 A g−1. Moreover, the electrode, had great cycling stability, retaining 83.9% of its capacity at 6 A g−1 after 7000 cycles. The asymmetric supercapacitor made of CoP@Ni(OH)2//activated carbon delivered 53.2 W h kg−1 at 800 W kg−1.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Chengbo Wei,Chuan Liu,Linna Gao,Yanfang Sun,Qingyun Liu,Xiao Zhang,Jinxue Guo
Integrating heterogeneous hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalysts into compatible composite catalysts with specific interfaces and structures holds great promise for the development of efficient bifunctional catalysts for overall water splitting. Herein, heterogeneous MoS 2 -Ni(OH) 2 catalyst supported by Ni foam (MoS 2 @Ni(OH) 2 /NF) is developed, in which the Ni(OH) 2 nanorod array is grafted with MoS 2 nanosheets . The hierarchical 1D/2D structures benefit not only the exposure of catalytic site but also the facilitated charge transfer. The heterointerfaces allow the synergism of electric structure modulation for improved catalytic activity and kinetics towards HER, OER, and overall water splitting. MoS 2 @Ni(OH) 2 /NF achieves a current density of 10 mA cm −2 at low overpotentials of 134 and 233 mV for HER and OER in 1 M KOH, respectively. Moreover, a cell voltage as low as 1.46 V is obtained to afford 10 mA cm −2 in a tow-electrode electrolyzer using MoS 2 @Ni(OH) 2 /NF as bifunctional catalysts, assuring it superior to most of the reported noble-metal-free bifunctional electrocatalysts. Such heterogeneous design of composite catalyst should shed light on the exploration of functional materials for energy applications.
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2017
·Vol. 19
·期 38
·5780-5786
·
IF 3.474
Kun Ding,Xiao Zhang,Juping Li,Ping Yang,Xin Cheng
Ultrathin α-Co(OH)2 nanosheets (NSs) were hydrothermally synthesized without using surfactants and templates. Interestingly, the ultrathin α-Co(OH)2 NSs evolved from graphene-like NSs to hexagonal nanoplates (NPs) and then transformed into a needle-like Co(CO3)0.5(OH)·0.11H2O phase with increasing reaction temperature and time. The phase and morphology evolution depended strongly on the CO32− ions in the solution. We ruled out the possibility that CO32− originated from the adsorption of CO2 in air and proposed the possible phase transition mechanism from α-Co(OH)2 to Co(CO3)0.5(OH)·0.11H2O, which was due to the decomposition of hexamethylenetetramine driven by dynamics and thermodynamics. The morphology evolution could be regarded as the dissolution–recrystallization–redissolution–recrystallization of α-Co(OH)2. The electrochemical behavior tests demonstrated that the ultrathin α-Co(OH)2 electrode exhibited an excellent specific capacitance of 833.4 F g−1 at 5 A g−1; however, the specific capacitance of the needle-like Co(CO3)0.5(OH)·0.11H2O electrode was 247.2 F g−1 at the same current density. This excellent electrochemical property is attributed to the crystalline phase and ultrathin nature of the materials.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2017
·
IF 5.951
Yan Gao,Lu Ye,Shuyan Cao,Hu Chen,Yanan Yao,Jian Jiang,Licheng Sun
Perovskite hydroxide CoSn(OH)6 nanoparticles were synthesized and used for the first time in the photocatalytic reduction of CO2 to CO. Under mild reaction conditions and using [Ru(bpy)3](PF6)2 as the photosensitizer, a high photocatalytic efficiency of 19.3 μmol for CO evolution with a high selectivity of 86.46% was obtained. The photocatalytic activity and CO selectivity were further improved by adding weak Brönsted acids, as proton sources, to the system.
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES COMMUNICATIONS
·
2024
·
IF 6.5
Qixiong Zhang,Yafei Hou,Qi Yang,Jing Cuan,Weiping Li
High energy storage in multilayer composites is pivotal for the progress of advanced electronic and power device systems, however, the uneven distribution of electric fields caused by significant dielectric contrast between adjacent layers limits its potential gaining in energy density. Through incorporating transition layers into multilayer composites to mitigate interlayer dielectric contrast, herein, four-layer matrix gradient-structured composites ( x vol% PMMA/(100- x ) vol% P(VDF-HFP) have been designed and fabricated. The results demonstrate that the transition layers play a crucial role in hindering the breakdown process and homogenizing the electric field distribution. In addition, the linear PMMA as well as horizontally oriented nanoplates are also beneficial in enhancing their energy storage performances. The gradient-structured composite ultimately achieved an energy density of 24.3 J/cm³ and a charge-discharge efficiency of 86.6 % at 676.8 MV/m, significantly surpassing that of traditional multilayer nanocomposites. The strategies proposed here may represent a universal approach to further enhance energy storage performances of multilayer composites.
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2014
·Vol. 7
·期 5
·1963-1969
·
IF 6.739
Pei Hu,Dongfang Hou,Yanwei Wen,Bin Shan,Chaoji Chen,Yunhui Huang,Xianluo Hu
Novel three-dimensional (3D) hierarchical Nb3O7(OH) nanostructures with a sheaf-like nanoarchitecture were fabricated for the first time by a hydrothermal process. Interestingly, the nanosheafs are composed of nanorods with an average diameter of about 25 nm. The as-prepared 3D hierarchical nanostructures possess a high surface area of 77 m2 g−1 with pore diameters of ca. 4.2–12.5 nm. A possible growth mechanism based on the combined Ostwald ripening and self-assembly process was proposed. It is found that both the valence-band top and the conduction-band bottom consist of O 2p and Nb 4d orbitals. Importantly, the 3D hierarchical Nb3O7(OH) nanostructures exhibit enhanced photocatalytic activity for the degradation of Rhodamine B (RhB) under UV-visible light, which is attributed to the unusual hierarchical structure, high surface area, and hybridization of energy bands.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2015
·
IF 3.942
Cen Tang,Yanxia Jin,Jiqing Lu,Xiaonian Li,Guanqun Xie,Mengfei Luo
A series of Mg catalysts supported on SiO 2 were prepared by an incipient wetness impregnation method and tested for gas phase dehydrochlorination of 1,1,2-trichloroethane. It was found that these catalysts were very active and selective for the reaction. The catalytic performance depended on the Mg loading rather than the Mg precursors as the catalysts using Mg(NO 3 ) 2 ·6H 2 O and MgCl 2 ·6H 2 O as the precursors showed the similar performance. A catalyst containing 10 wt.% of Mg showed the best performance with a steady state TCE conversion of 92% and cis -dichloroethene selectivity of 91%. Moreover, characterizations of the catalysts revealed the formation of Cl-containing Mg species on the surface during the reaction. The analyses of the compositions of the stable catalysts under working conditions indicated a Cl/Mg ratio of 1, suggesting that Mg(OH)Cl could be the active sites for the reaction.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）