International Journal of Electrochemical Science
·
2023
·
IF 1.5
Qiuchan Huang,Shengzhou Chen,Tingting Ma,Hanbo Zou,Wei Yang
TiN supported Co-Mo nitride nano particles were synthesized via a modified sol-gel method, and then nitrided under NH 3 atmosphere at 700 °C. The samples obtained were characterized by XRD, XPS, HRTEM and SAED techniques and tested as catalysts for oxygen reduction reactions (ORR) in acid medium. The synergistic effect of the cobalt and molybdenum nitrides on nanosized TiN leads to a good ORR catalytic activity. The onset potential for the Co 1 Mo 1 Nx/TiN-6 catalyst was shifted to a more positive value 0.347 V versus SCE and the reduction peak located at 0.273 V versus SCE (0.401 V of Pt/C at the same condition). The number of electron transfer was tested by a rotating disk electrode which was in concordance with a two-electron mechanism at the potential 0.2 V versus SCE and it increased to four-electron in the negative values of the potential -0.2 V versus SCE. HRTEM showed that the nanoscale Co 2 N and MoN were still highly dispersed on the surface of TiN though heated at high temperature. This work clearly indicates that the oxygen reduction active center of Co-Mo-N/TiN catalyst was the mixture of Co 2 N and MoN.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Lina Wang,Jinxing Yu,Zhuo Li,Xiaoxiang Xu
LaTiO 2 N is a promising photocatalyst for solar water splitting but is generally subject to a low activity due to inadequate separation of photocarriers (i.e . e - and h + ). Loading noble metal cocatalysts such as Pt often has limited improvements because of their Schottky-type interfaces with LaTiO 2 N, resulting in a deficient electron collection at the surface catalytic sites. In this work, TiN nanoparticles have been firmly anchored at the surface of mesoporous single-crystalline LaTiO 2 N. As opposed to Pt, TiN has an ohmic contact with LaTiO 2 N due to a comparable work function and the structurally matched heterointerfaces. Such a tight and ohmic connection enables TiN to readily collect electrons from LaTiO 2 N, which in turn substantially improves the photocarrier separation and photocatalytic activity. These findings justify that TiN is an ideal relay for electron transfer between n-type semiconductors and noble metal cocatalysts which would otherwise be very difficult when the Schottky-type interfaces are formed.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2023
·Vol. 30
·期 9
·1740-1747
·
IF 4.8
Cai Dawei,Zhang Li,Wang Wanlin,Zhang Lei,Sohn Il
Mold flux serves the crucial metallurgical function of absorbing inclusions, directly impacting the smoothness of the casting process as well as the cast slab quality. In this study, the dissolution behavior and mechanism of TiO 2 and TiN inclusions in molten CaO–SiO 2– B 2 O 3 -based fluorine-free mold flux were explored by in situ single hot thermocouple technology combined with X-ray photoelectron spectroscopy. The results showed that TiO 2 inclusions are effectively dissolved by the molten slag within 76 s, during which the original octahedral [TiO 6 ] 8− structures are destroyed and convert to the networker tetrahedral [TiO 4 ] 4− structures. However, the dissolution rate is much lower for TiN inclusions than for TiO 2 inclusions. This can be attributed to the fact that the TiN particles need to be oxidized and then dissolved in the molten slag to form tetrahedral [TiO 4 ] 4− and octahedral [TiO 6 ] 8− structures during the TiN inclusion dissolution process, which is accompanied by the generation of a large amount of N 2 gas. Moreover, CaTiO 3 crystals tend to nucleate and grow on bubble surfaces with sufficient octahedral [TiO 6 ] 8− structures and Ca 2+ ions, eventually resulting in the molten slag being in a solid–liquid mixed state.
研究领域:
冶金学
·
材料科学
·
铸造过程
✓ 已验证
DOI
高影响因子
Energy Storage Materials
·
2021
·
IF 17.789
Linlin Ma,Li-Juan Yu,Jingchong Liu,Ya-Qiong Su,Shuai Li,Xiaohuan Zang,Tao Meng,Shuaihua Zhang,Jianjun Song,Jiangyan Wang,Xiaoxian Zhao,Zhimin Cui,Nü Wang,Yong Zhao
As the desired sulfur host of lithium-sulfur battery, the strong polarity and fast electron migration capability are indispensable for achieving effective adsorption and conversion of lithium polysulfides (LiPSs), that is, restricting the shuttle effect. Herein a porous microdisk Ti 4 O 7 /TiN/C heterojunction with strong polar N-Ti-O covalent bonds is precisely constructed. Compared with O-Ti-O or N-Ti-N bond in single Ti 4 O 7 or TiN , the N-Ti-O bond with stronger polarity could adsorb and bond with S and Li atoms in LiPSs, which is beneficial for LiPSs adsorption. Beside, the Ti 4 O 7 /TiN heterostructure favors the electron transfer , which could promote the conversion of LiPSs. The design strategy is to construct abundant polar N-Ti-O bonds at Ti 4 O 7 /TiN heterogeneous interface that would realize the associative process of LiPSs adsorption, trapping, and conversion, thereby restraining the shuttle effect efficiently. In the current study, as the host of the sulfur cathode, the porous microdisk TiN/Ti 4 O 7 /C heterojunction exhibits a high specific capacity of 1204.5 mAh g −1 at 0.2 C, and a high specific capacity of 616.5 mAh g −1 at an ultrahigh current density of 4 C. In addition, 86.4% and 116.9% capacity are retained over 1000 cycles at 1 C and 2 C, respectively. This strategy provides an insight into developing lithium-sulfur battery with extraordinary performance, and opens promising routes to design the next-generation electrochemical energy storage devices.
研究领域:
材料科学
·
电化学能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2017
·
IF 2.764
Chao Li,Weiyi Yang,Qi Li
To develop TiO 2 -based photocatalysts with visible light activity for better solar energy utilization, a simple flash oxidation method was developed by calcining commercial TiN nanoparticle to prepare N-doped TiO 2 photocatalyst and TiN/TiO 2 composite photocatalysts through the modulation of the calcination time and temperature. It was found that more energy and processing time were needed to prepare N-doped TiO 2 photocatalyst than that of TiN/TiO 2 composite photocatalyst during this process, while TiN/TiO 2 composite photocatalyst had a better visible light absorption/photocatalytic performance than that of N-doped TiO 2 photocatalyst prepared from the oxidation of the same TiN precursor. Thus, the preparation of TiN/TiO 2 composite photocatalyst from TiN precursor should be a more preferred approach than the preparation of N-doped TiO 2 photocatalyst for visible-light-activated photocatalysis for its cost-effectiveness.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2021
·
IF 3.383
Shi Tian,Wenchao Guo,Qianglong He,Aiyang Wang,Tian Tian,Chun Liu,Lanxin Hu,Zhixiao Zhang,Hao Wang,Weimin Wang,Zhengyi Fu
TiN–TiB 2 –hBN composite powders were synthesized by a nitride boronizing process using TiN and amorphous boron as the raw materials, and the reaction process of TiN–B powder mixture was investigated by heat treatment at elevated temperatures. At 1400 °C in a vacuum, TiN–TiB 2 –hBN composite powders with a core-shell structure of layered hBN-wrapped TiB 2 were obtained, which can be used to prepare ceramic composites with excellent properties. The results showed that B atoms began to diffuse into TiN and replace the N atoms to form TiB 2 at high temperature; then, the substituted N escaped outwards, and upon contacted with B, formed hBN at the surface of the TiB 2 particles. The relative density, bending strength , and fracture toughness of the 70 vol% TiN–17.6 vol% TiB 2 –12.4 vol% hBN (TB73) composite prepared by reactive sintering were 98.90%, 521 MPa, and 4.22 MPa m 1/2 , respectively, which were much higher than that of fabricated via conventional method (TBN73: 88.02%, 198 MPa, and 2.58 MPa m 1/2 ).
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 9
·4807-4815
·
IF 11.301
Ying Gu,Aiping Wu,Lei Wang,Dongxu Wang,Haijing Yan,Peng Yu,Ying Xie,Chungui Tian,Fanfei Sun,Honggang Fu
Single-atom catalysts (SACs) have been promising in various catalytic fields, but the controllable synthesis of SACs with high stability remains challenging. Here, we show a robust strategy toward the fabrication of highly efficient and stable SACs based on the “competitive occupancy” of two metal (M) species on graphene oxide (GO). The abundant M1 (Ti) species predominantly occupy more groups of GO, thereby leaving a tiny number of groups in the gaps of the M1 species to combine with M2 (Co2+, etc.) species. Consequently, this guarantees the formation of Co–N4 SACs embedded in 2D TiN/rGO sheets during nitridation. Further, TiN can act as a “spacer” to prevent Co–N4 from aggregation, thereby improving catalyst stability. Co–N4/TiN–rGO exhibits outstanding catalytic performance for the fast conversion of highly concentrated aromatic nitro compounds (∼0.3–2 mM) into amino compounds and excellent recyclability, which is the best among reported catalysts. In contrast, TiN/rGO has no obvious activity, and Co4N–rGO prepared without Ti competition shows poor activity and stability, which indicates the vital role of Co–N4 and TiN for obtaining the remarkable catalytic ability of Co–N4/TiN–rGO. The reaction mechanism is also proposed based on theoretical calculations. The strategy can be used to design Ni (Fe, Cr, Cu)-based SACs.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 30
·2300378
·
IF 13.3
Qian Zhao,Xiulong Wu,Shenghu Li,Qiaotian Zheng,Shuai Jiang,Ye Xu,Bin He,Ling Ma,Yangtong Luo,Yujue Wang,Wanglai Cen,Yan Meng,Dan Xiao
Currently, the commercial separator (Celgard2500) of lithium-ion batteries (LIBs) suffers from poor electrolyte affinity, mechanical property and thermal stability, which seriously affect the electrochemical performances and safety of LIBs. Here, the composite separators named PVDF-HFP/TiN for high-safety LIBs are synthesized. The integration of PVDF-HFP and TiN forms porous structure with a uniform and rich organic framework. TiN significantly improves the adsorption between PVDF-HFP and electrolyte, causing a higher electrolyte absorption rate (192%). Meanwhile, XPS results further demonstrate the tight link between PVDF-HFP and TiN due to the existence of Ti F bond in PVDF-HFP/TiN, resulting in a strong impediment for the puncture of lithium dendrites as a result of the improved mechanical strengths. And PVDF-HFP/TiN can effectively suppress the growth of lithium dendrites by means of uniform lithium flux. In addition, the excellent heat resistance of TiN improves the thermal stability of PVDF-HFP/TiN. As a result, the LiFePO 4 ||Li cells assembled PVDF-HFP/TiN-12 exhibit excellent specific capacity, rate performance, and capacity retention rate. Even the high specific capacity of 153 mAh g −1 can be obtained at the high temperature of 80 °C. Meaningfully, a reliable modification strategy for the preparation of separators with high safety and electrochemical performance in LIBs is provided.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Baosong Li,Dandan Li,Wei Chen,Yuying Liu,Jun Zhang,Yulei Wei,Weiwei Zhang,Wanchun Jia
Ni-W/TiN nanocomposite coatings were successfully prepared via pulse electroplating from an electrolyte containing suspended TiN nanoparticles . The effects of applied current density and deposition time on microstructure, morphology, composition, hardness and electrochemical behaviors of the obtained coatings were investigated. Results showed that the current density and deposition time affect remarkably the electrochemical co-deposition process and then the structure and characteristics of the composites. It illustrated that the nanocomposites are uniform, compact and crack-free. The nanocomposites prepared at I a = 3 A dm −2 and t = 20 min had the finest structure, showing a fine and smooth surface. EDS mapping and XPS spectra illustrated that the TiN nanoparticles had been homogeneously dispersed throughout the coating. 2.34 wt% TiN nanoparticles were embedded in Ni–W (68.56 wt% Ni and 29.1 wt% W) alloy matrix at I a = 3.0 A dm −2 . The inclusion of TiN nanoparticles in Ni–W could promote the nucleation and cause a distinct microstructural change. The crystallite size was in the range of 11–15 nm. The average roughness value ( R a ) is 65.7 nm and 73.8 nm for coating formed at 20 min and 40 min, respectively. The electrochemical measurements illustrated that I a = 3–5 A dm −2 and t = 40–60 min was the optimal operating parameters for the excellent anti-corrosion properties of Ni–W/TiN nanocomposites. The embedded TiN in Ni–W matrix could fill defects then improve its corrosion resistance . This electrodeposited Ni–W/TiN nanocomposites possess excellent hardness and superior corrosion resistance , and is expected to be applied in aggressive environment as a protective coating.
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 MATERIALS ENGINEERING AND PERFORMANCE
·
2016
·Vol. 26
·期 1
·51-60
·
IF 1.094
Hu Jiaoyu,Liu Jun,Wang Chunxia,Tang Xin
The core/shell nano-TiN-coated Al powders (TiN/Al) were prepared and added into A356 alloy by ultrasonic-assisted casting method in this work. The results show that TiN/Al has a better dispersion in A356 matrix and a stronger strengthening effect than TiN without the core/shell structure. With the addition of TiN/Al, most of the coarse primary α-Al dendrites of A356 turn into equiaxial. After T6 heat treatment, it is found that eutectic silicon in A356 with TiN/Al becomes columnar or globular in shape and smaller in size, which causes a greatly enhanced elongation of 11.7%. The results also suggest that the addition of nanoparticles can affect the precipitation behaviors and change the shapes and sizes of the precipitation.
研究领域:
材料科学
·
金属材料
·
凝固技术
·
复合材料
·
材料加工工程
✓ 已验证
DOI
高影响因子
SURFACE REVIEW AND LETTERS
·
2018
·
IF 0.734
GAO PINGPING,OUYANG CHUN,XIE ZHIYONG,TAO TAO
The Ni-P/TiN coating was used as bipolar plate by electroless plating on Ti. Surface morphology and phase structure of the coatings were characterized by SEM and XRD, respectively. Corrosion resistance of Ni-P and Ni-P/TiN coating was measured in the simulated solution of Proton exchange membrane fuel cells (PEMFCs). The interfacial contact resistance (ICR) was conducted by applied different forces. SEM images indicated that the particles of core–shell structure were formed on the surface of coating on Ti substrate. The core–shell structure was composed of TiN core and Ni-P electroless plating shell. Compared with Ni-P coatings, the Ni-P/TiN coating showed better corrosion resistance behaviors and low ICR (below 10 m Ω cm − 2 under pressure of 200 N/cm 2 ) . TiN particles and distribution of core–shell were in favor of the formation of coating and compact surface morphology. The good conductivity was attributed to the compact surface morphology of coating. The Ni-P/TiN coating showed excellent interfacial conductivity and good corrosion resistance at applied high potential in simulated solution of PEMFCs.
研究领域:
材料科学
·
能源工程
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES COMMUNICATIONS
·
2022
·
IF 7.685
Meng Liu,Zhaozhu Zhang,Yanling Wang,Peilong Li,Mingming Yang,Junya Yuan
Herein, TiN@ZIF-8 hybrid with hierarchical structure was constructed by in situ growth of Zeolitic Imidazolate Frameworks-8 (ZIF-8) onto the TiN surface via a PDA/PEI (polydopamine/polyethyleneimine) intermediate layer. The characterization of structure and chemical composition affirmed the successful assembly of TiN@ZIF-8 hybrid and the specific surface area of TiN@ZIF-8 hybrid showed a sharp increase from 3.5 m 2 /g for pristine TiN to 183.4 m 2 /g. The resulted TiN@ZIF-8 hybrid was aimed at strengthening the mechanical and tribological properties of fabric composites . The results demonstrated that the tensile strength of TiN@ZIF-8/fabric composites presented an increase by 48% due to the stress transfer and reinforcement of TiN@ZIF-8. Additionally, the incorporation of TiN@ZIF-8 restricted the moving of resin molecular chain and escape of decomposition products, contributing to the improvement in heat resistance of fabric composites. Friction and wear tests indicated that the abrasion resistance of TiN@ZIF-8/fabric composites was significantly improved in comparison with pristine composites because the ZIF-8 loaded on the surface of TiN made for a more even dispersion of TiN, and the introduction of TiN@ZIF-8 contributed to forming a uniform, dense transfer film due to the synergistic enhancement between TiN and ZIF-8.
研究领域:
材料科学
·
表面工程
·
复合材料
✓ 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）