Materials Today Communications
·
2022
·
IF 3.662
Wei Qiang,Xiao Qu,Chuntao Chen,Lei Zhang,Dongping Sun
As a photocatalyst , titanium dioxide (TiO 2 ) suffers from the wide band gap and the quick carrier recombination process, thus leading to the inefficient use of solar energy and poor catalytic performance. Herein, in this work, TiO 2 /Ti 3 C 2 heterojunctions are designed to overcome these shortcomings via growing TiO 2 in situ on the titanium element of Ti 3 C 2 MXene . The TiO 2 /Ti 3 C 2 heterojunctions not only broaden the range of light absorption , but also hugely extend the lifetime of photogenerated carriers. Besides, the anatase TiO 2 with exposed (001) facets further enhances the catalytic properties. After optimizing the amount of TiO 2 /Ti 3 C 2 heterojunctions by controlling reaction time, 20 mg catalysts can degrade 97.6% of 30 mL tetracycline solution (15 mg/L) in 90 min under visible light . Even after five cycles, the degradation ability of TiO 2 /Ti 3 C 2 only changes from 97.6% to 94.3%. This paper offers another perspective on the synthesis of efficient and stable photocatalysts.
研究领域:
材料科学
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环境科学
·
化学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2015
·Vol. 44
·期 29
·13030-13039
·
IF 4.197
Hongmei Chen,Yinghao Xie,Xiaoqin Sun,Meilin Lv,Fangfang Wu,Lei Zhang,Li Li,Xiaoxiang Xu
Separation of photo-generated charges has played a crucial role in controlling the actual performance of a photocatalytic system. Here we have successfully fabricated g-C3N4/TiO2-B nanowire/tube heterostructures through facile urea degradation reactions. Owing to the effective separation of photo-generated charges associated with the type-II band alignment and intimate interfacial contacts between g-C3N4 and TiO2-B nanowires/tubes, such heterostructures demonstrate an improved photocatalytic activity over individual moieties. Synthetic conditions such as hydrothermal temperatures for the preparation of TiO2-B and the weight ratio of TiO2-B to urea were systematically investigated. A high crystallinity of TiO2-B as well as the proper growth of g-C3N4 on its surface are critical factors for a better performance. Our simple synthetic method and the prolonged lifetime of photo-generated charges signify the importance of type-II heterostructures in the photocatalytic applications.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 16
·3843
·
IF 4.2
Xinbao Li,Kai Sun,Ying Chen,Ye Yuan
As a widely used support, TiO2has often been combined with Pd to form highly sensitive gas-chromic materials. Herein, we prepared a series of Pd/TiO2catalysts with different Pd content (from 0.1 to 5 wt.%) by the impregnation method for their utilization in fast room-temperature CO detection. The detection was simply based on visible color change when the Pd/TiO2was exposed to CO. The sample with 1 wt.% Pd/TiO2presented an excellent CO gasochromic character, associated with a maximum chromatic aberration value of 90 before and after CO exposure. Systematic catalyst characterizations of XPS, FT-IR, CO-TPD, and N2adsorption–desorption and density functional theory calculations for the CO adsorption and charge transfer over the Pd and PdO surfaces were further carried out. It was found that the interaction between CO and the Pd surface was strong, associated with a large adsorption energy of −1.99 eV and charge transfer of 0.196e. The color change was caused by a reduction in Pd2+to metallic Pd0over the Pd/TiO2surface after CO exposure.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2018
·Vol. 102
·期 4
·2021-2028
·
IF 2.956
Xiaokai Li,Qiangqiang Zhu,Yangyang Xu,Xiaojian Mao,Minghui Feng,Benxue Jiang,Long Zhang
Highly transparent Y 2 O 3 ceramics using TiO 2 as an additive were synthesized by presintering and hot isostatic pressing (HIP). The effects of TiO 2 contents and sintering conditions on the optical properties of the final transparent ceramics were investigated. A small amount (0.04-0.16 wt%) may decrease the densification temperature by about 200°C. The Y 2 O 3 ceramics doped with 0.16 wt% TiO 2 revealed a transparency of 82% in the wavelength range 1-6 μm. The thermal conductivity of the samples is about 11.8 W/m K at 25°C, which is close to that of the undoped Y 2 O 3 ceramics.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
Electronic Materials Letters
·
2022
·Vol. 19
·期 1
·94-107
·
IF 3.151
Luo Menghao,Feng Hange,Hu Yuechuan,Chen Keke,Dong Zibo,Xue Shaolin
Abstract Photocatalytic degradation has received considerable emphasis since it shows significant possibilities in environmental pollution. In this work, ternary Z-scheme heterojunction g-C 3 N 4 /TiO 2 /Ti 3 C 2 photocatalysts are designed and fabricated. The Z-scheme heterojunctions formed on the surfaces of g-C 3 N 4 and TiO 2 dramatically modify the photocatalytic performances of the compound under illumination. Meanwhile, in this process, multilayer Ti 3 C 2 , as the transport medium of Z-scheme heterojunction, is tightly bonded to TiO 2 generated by hydrothermal oxidation and g-C 3 N 4 with large specific surface area, which effectively facilitates the space charge separation and depresses the charge recombination. When the addition amount of TiO 2 /Ti 3 C 2 is 80 mg and calcined at 450 ℃ for 4 h, g-C 3 N 4 /TiO 2 /Ti 3 C 2 has the greatest photocatalytic performance, and the kinetic constant for degradation methyl orange (MO) was about 3.62 times that of g-C 3 N 4 and 14.55 times that of Ti 3 C 2 , respectively. This work illustrates that g-C 3 N 4 /TiO 2 /Ti 3 C 2 has outstanding potential and offers novel insights for designing and synthesizing new ternary heterojunction materials. Graphical Abstract
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 30
·305704
·
IF 3.551
Hong Li,Weizhe Song,Xingqiang Cui,Yanhui Li,Baorong Hou,Xiaoping Zhang,Yuqi Wang,Lianjun Cheng,Pengfei Zhang,Junru Li
AgInS2 nanoparticle and graphene nanosheet co-sensitized anatase TiO2 nanotube array films were fabricated by a combination of hydrothermal reaction and electrochemical anodization on titanium sheets. The results showed that the co-sensitization of AgInS2 nanoparticles and graphene nanosheets extended the photoresponse of TiO2 nanotubes into the visible-light region, and improved the photogenerated charge separation and transfer capability. The photocurrent density of the AgInS2/graphene/TiO2 composites (about 4.0 mA cm−2) was 20 times that of bare TiO2 (only 0.2 mA cm−2) under visible-light illumination. The potential negative shift value of AgInS2/graphene/TiO2 composites was up to 0.68 V versus saturated calomel electrode. The AgInS2/graphene/TiO2 composites can provide Q235 carbon steel with highly efficient photocathodic protection under visible-light illumination.
研究领域:
材料科学
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电化学
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腐蚀防护
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 26
·15033-15041
·
IF 3.049
Ya Gao,Yongjie Zheng,Jixing Chai,Jingzhi Tian,Tao Jing,Deqing Zhang,Junye Cheng,Huiqing Peng,Bin Liu,Guangping Zheng
Effective separation and rapid transfer of photogenerated electron–hole pairs are key features of photocatalytic materials with high catalytic activity, which could be achieved in co-catalysts. It is reported that the two-dimensional (2D) MoS2 is a promising co-catalyst due to its unique semi-conductive properties and graphene-like layered structure. However, the application of MoS2 as a co-catalyst is limited by its poor electrical conductivity. On the other hand, it is worth noting that TiO2 possesses reactive crystal facets, which is one of the dominant mechanisms for the separation of photogenerated electron–hole pairs. In this work, we prepared MoS2/RGO hybrids as co-catalysts which were doped to TiO2 with highly reactive {001} planes via the hydrothermal method. It was found that the {001}-TiO2/MoS2/RGO photocatalysts with 7 wt% MoS2/RGO co-catalyst show the highest photodegradation activity for the degradation of Rh B under visible light irradiation (λ > 400 nm), which could result from the synergy of the effective separation of electron–hole pairs by the {001} facets in TiO2 and the rapid transfer of electron–hole pairs in MoS2/RGO. The results show that the {001}-TiO2/MoS2/RGO hybrid is a low-cost and stable photocatalyst for the effective degradation of Rh B under visible light.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2017
·
IF 3.582
Haiyan Shen,Dawei Ni,Ping Niu,Yi Zhou,Tianyou Zhai,Ying Ma
Spatially controlled co-loading of both oxidation and reduction cocatalysts on semiconductor photocatalysts has been demonstrated to be favorable for photogenerated charge separation and thus enhanced photocatalytic activity. Herein, we presented a simple ball-milling method to improve photocatalytic H 2 production of TiO 2 by co-loading of oxidation cocatalyst Co 3 O 4 with reduction cocatalyst CuO , wherein the Co 3 O 4 loading amount was significant especially for TiO 2 loaded with sufficient or optimum CuO. In comparison with that on TiO 2 loaded with only CuO, the photocatalytic H 2 production from water over TiO 2 photocatalyst co-loaded with CuO and trace Co 3 O 4 was enhanced by approximately 5.5 times, even though complex spatial control was not adopted. In contrast, remarkable improvement of photocatalytic activity after Co 3 O 4 co-loading was only observed on TiO 2 photocatalysts loaded with less CuO in the presence of methanol. Better separation of photogenerated charges on the surface of dual-cocatalysts modified TiO 2 was further demonstrated by decreased luminescence as well as increased photogenerated electrons and hydroxyl radicals as compared to those loaded with only CuO.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 48
·e202303437
·
IF 2.1
Ms. Menghan Li,Xuan Luo,Tongming Su,Xinling Xie,Hongbing Ji,Zuzeng Qin
Graphical Preparation of NiZr/N-doped TiO 2 /Ti 3 C 2 catalyst for catalytic cinnamaldehyde (CAL) hydrogenation by KBH 4 reduction. N-doped TiO 2 on Ti 3 C 2 , and N-doping substituted O in the TiO 2 lattice to create oxygen vacancies on the surface, increase the surface acidity, and adsorb C=O bonds, which resulted in high cinnamaldehyde conversion and cinnamyl alcohol (COL) selectivity after reaction 8 h. An NiZr/N-doped TiO 2 /Ti 3 C 2 catalyst was prepared by KBH 4 reduction for cinnamaldehyde hydrogenation. Characterization results showed that the synthesis of N-doped TiO 2 on Ti 3 C 2 and the uniform dispersion of TiO 2 on the Ti 3 C 2 surface increased the specific surface area of NiZr/Ti 3 C 2 by 164.4 m 2 /g. N-doping at a level of 19.03 % was used to replace O in the TiO 2 lattice; the Ti−O−Ti peak in the XPS spectrum of the undoped catalyst was shifted by 0.3 eV in the spectrum of the doped catalyst; as a result, there was a 15.40 % increase in the number of surface oxygen vacancies of the NiZr/Ti 3 C 2 catalyst. The synthesis of N-doped TiO 2 on Ti 3 C 2 converted the moderately acidic sites of NiZr/Ti 3 C 2 to strong Lewis acid sites and increased the total number of acid sites by approximately 0.8-fold. The active Lewis acid sites on the surface of NiZr/N-doped TiO 2 /Ti 3 C 2 adsorbed only C=O bonds and inhibited the adsorption of C=C bonds, resulting in a high cinnamaldehyde conversion of 90.69 % and a cinnamyl alcohol selectivity of 91.87 %.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Carbon Letters
·
2023
·Vol. 33
·期 5
·1395-1406
·
IF 4.5
Chen Zhangjing,Li Liangliang,Cheng Gang
Photocatalytic CO 2 reduction is a promising approach for reducing CO 2 emissions and achieving the goal of carbon neutrality. In this work, selectively coupling Cu(OH) 2 and CuO with amine-modified brookite TiO 2 (NH 2 –B–TiO 2 ) has been achieved by a simple precipitation method. The results show that CuO is better than Cu(OH) 2 as a co-catalyst to enhance the CO 2 photoreduction capability of NH 2 –B–TiO 2 . The highest rates of CO 2 conversion to CH 4 and CO of NH 2 –B–TiO 2 –CuO composite reach 6.05 and 3.25 μmol h −1 g −1 , respectively, which is higher than 8 times the yield of CH 4 of NH 2 –B–TiO 2 . It is proposed that the NH 2 –B–TiO 2 –CuO composite offers an effective charge transfer through the formation of a p–n junction between NH 2 –B–TiO 2 and CuO interfaces, while in the NH 2 –B–TiO 2 –Cu(OH) 2 composite, the Cu(OH) 2 dominantly serves as an electron sink to capture photo-induced electrons, promoting photo-induced carrier separation. This work provides an ingenious synthetic method for selectively anchoring Cu(OH) 2 and CuO on semiconductors with different charge transfer routes for an efficient CO 2 photoreduction. Graphical abstract
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Catalysts
·
2020
·Vol. 10
·期 10
·1126
·
IF 3.52
Jun Liu,Xuli Li,Haobo Hou,Min Zhou
To further boost the charge separation and photocatalytic activity of TiO2under visible light, the anatase–rutile mixed-phase nitrogen-doped (N-doped) TiO2nanoparticles were successfully synthesized through a facile one-step calcining procedure using TiN as raw materials. The crystal phases, morphologies, chemical compositions, textural structures, and optical properties of as-obtained N-doped TiO2were characterized by the corresponding analytical techniques. The photocatalytic activities of as-fabricated samples were evaluated by degrading 4-chlorophenol (4-CP) and methylene blue (MB) aqueous solution under visible light irradiation. The results revealed that the ratio of rutile to anatase increased with the improvement of sintering temperature, and the sample prepared at 500 °C had the best photocatalytic activity. This might be because it possessed the most appropriate rutile/anatase proportion as well as the nitrogen doping. The transient photocurrent responses, photoluminescence spectra (PL) measurements, and active species trapping experiments were implemented to disclose the photocatalytic mechanism. This work will provide a further insight into the synthesis of highly efficient N-doped TiO2photocatalysts for organic contaminant removal.Keywords:N-doped TiO2;charge separation;photocatalytic activity
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
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Wenxiang Yang,Guozhi Ma,Yin Fu,Ke Peng,Hongli Yang,Xiaoqiang Zhan,Weiyou Yang,Lin Wang,Huilin Hou
The development of novel and efficient heterojunction photocatalysts is still a challenging issue for achieving highly efficient solar-to-chemical energy conversion. Herein, we report the construction of Ti 3 C 2 MXene@TiO 2 /CuInS 2 (M@T/CIS) integrated Schottky/step-scheme (S-scheme) heterojunction by two-step hydrothermal process for boosting photocatalytic hydrogen generation activity. The as-prepared M@T/CIS hybrid photocatalysts exhibit the synergistic effects for enhanced visible-light harvesting, improved charge transfer and increased active site for photocatalytic H 2 evolution. They deliver a H 2 evolution rate of 356.27 μmol g -1 h −1 , which is ∼ 69 and 636 times higher than those of M@T and CIS, respectively, representing their potential applications towards photocatalytic H 2 evolution.
研究领域:
材料科学
·
能源转换技术
✓ 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）