Search query: BCN TiO2

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abstract: Abstract In this work, BCN TiO2(A+R) heterojunctions were constructed via a simple one step calcination method as efficient photocatalysts for H2 evolution. Simultaneously, an anatase/rutile phase junction was also obtained due to the crystalline phase transformation that occurred during high temperature calcination. The unique heterojunction and phase junction lead to the formation of an intimate interface and large contact area between two semiconductors and extended the visible light absorption range. Therefore, BCN TiO2(A+R) heterojunctions with a mixed anatase and rutile phase exhibit enhanced photocarrier separation efficiency, realizing an eleven fold increase in the electron lifetime compared to that of pure TiO2 and yielding a remarkable visible light driven H2 evolution rate nearly 7.5 and 12.2 times higher than that of TiO2(A+R) and pure BCN, respectively. This work provides a new strategy for designing efficient water splitting photocatalysts with highly efficient charge separation and transfer.
author_names: Xiaolei Xing

Huihui Zhu

Min Zhang

Limin Xiao

Qiuye Li

Jianjun Yang
title: Effect of heterojunctions and phase junctions on visible light photocatalytic hydrogen evolution in BCN TiO2 photocatalysts
venue: Chemical Physics Letters
year: 2019

abstract: All solid state Z scheme BCN TiO2 binary heterostructures with a surface oxygen vacancy layer as the contact interface are fabricated by NaBH4 reduction and ball milling. The effect of the surface oxygen vacancy layer of BCN TiO2 binary heterostructures on the charge carrier transfer and photocatalytic hydrogen evolution was thoroughly investigated. UV vis diffuse reflection spectra results reveal that the surface oxygen vacancy can extend the light absorption from the UV to the visible light region for BCN TiO2 binary heterostructures. The steady state/time resolved photoluminescence spectra exhibit an increased charge carrier lifetime, improved charge carrier separation efficiency and strengthened direct Z scheme charge transfer process for BCN TiO2 x heterostructures. As expected, the BCN TiO2 x heterostructures exhibited a higher visible light photocatalytic efficiency, about 7 and 11 times higher than that of the pure TiO2 and BCN samples. Namely, the photocatalytic activity of hydrogen evolution can be greatly promoted by constructing the surface oxygen vacancy layer. This work provides a new pathway to construct an efficient contact layer for the direct Z scheme system to improve the charge carrier separation and transfer and thereby improve the photocatalytic activity.
author_names: Xiaolei Xing

Huihui Zhu

Min Zhang

Lili Hou

Qiuye Li

Jianjun Yang
title: Interfacial oxygen vacancy layer of a Z scheme BCN TiO2 heterostructure accelerating charge carrier transfer for visible light photocatalytic H2 evolution
year: 2018

abstract: Abstract BCN TiO 2 nanocomposites are obtained by a simple calcination method using a hexagonal boron carbon nitride (BCN) semiconductor and nanotubular titanic acid (NTA) as precursors. The BCN TiO 2 nanocomposites are characterized systematically by XRD, TEM, XPS, DRS, ESR, BET, I t and PL techniques. Compared with the novel TiO 2 or single BCN sample, the BCN TiO 2 nanocomposites prepared by a calcination method show the highest photocatalytic activity for hydrogen production under visible light irradiation. The photocatalytic activity of BCN TiO 2 nanocomposites is optimized by changing the amount of BCN. Characterization results confirm that a large amount of single electron oxygen vacancies can be formed when NTA was calcined at the higher temperature, which is beneficial to the enhancement of visible light absorption and the transfer of photogenerated carriers due to the formation of ohmic contact at the interface between BCN and novel TiO 2 Therefore, the visible light photocatalytic activity for H 2 production of BCN TiO 2 nanocomposites has been improved significantly by the formation of BCN TiO 2 Z scheme photocatalyst, which results in efficient space separation of photo induced charge carriers.
author_names: Xiaolei Xing

Min Zhang

Lili Hou

Limin Xiao

Qiuye Li

Jianjun Yang
title: Z scheme BCN TiO2 nanocomposites with oxygen vacancy for high efficiency visible light driven hydrogen production
year: 2017

abstract: BCN TiO2 was prepared by doping Ti(OH)4 with graphite like structure BCN in an annealing process at 400[degC] for 2[h] The catalyst samples were characterized by X ray diffraction (XRD) X ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) Graphite like structure BCN was detected by XRD. The results showed that with graphite like structure BCN doped in, the crystal size became smaller than pure TiO2. Also B, C, N were detected in crystal lattice of TiO2, in which Boron was in the form of Bx+ Carbon substituted some of the lattice oxygen atoms as Ti C, and Nitrogen was in the form of Ti N and Ti O N.
author_names: L Zhang

Ling Li

Zonggang Mou

Xifeng Li
title: Preparation and Characterization of BCN TiO2 Nanoparticles
year: 2011

abstract: Ti3+ self doped TiO2/BCN heterojunction (Ti3+ TiO2/BCN) was constructed via a hydrothermal method with using NaBH4 as reducing agent. The BCN nanosheets function as a good support to block the agglomeration of Ti3+ TiO2 nanoparticles, which decreased the recombination of photogenerated charge carriers. The Ti3+ TiO2/BCN sample exhibited enhanced electronic conductivity and absorption in visible light region because of the introduction of Ti3+ and oxygen vacancies (Ov) The as prepared Ti3+ TiO2/BCN sample showed enhanced photoelectrochemical (PEC) performance as confirmed by analyses of LSV, EIS, Bode plots and M S. Under the visible light irradiation, the optimally Ti3+ self doped TiO2/BCN heterojunction sample yield a photocurrent density of 0.69 mA/cm2 at 1.23 V versus RHE, which is over three times as high as BCN and TiO2/BCN at the same conditions.
author_names: Zheng Liang

Junqi Li

Nan Ye Lei

Liu Guo

Qianqian Song
title: Construction of Ti3+ self doped TiO2/BCN heterojunction with enhanced photoelectrochemical performance for water splitting
venue: Journal of Materials Science: Materials in Electronics
year: 2018

abstract: Titanium dioxide has attracted much attention in the past decades. When it was doped by some elements, such as C, N, P, S and B, the conductibility will be obviously changed. In this work, the BCN doped TiO2 with nanostructured fllm was fabricated by co deposit method. The structure was studied by X ray difiraction measurement. The microstructure was observed by XPS. The investigation of ac impedance spectra for BCN doped TiO2 thin fllm was performed. The grain resistance, resistance of grain boundary, and the capacitance in the thin fllm were determined from impedance technique. 1. INTRODUCTION Recently, much progress has been achieved in the fleld of visible light active TiO2 by incorporation of various dopants into its lattice. Especially the doping of nonmetal, such as nitrogen, uorine, chlorine, sulfur, boron and carbon (1{5) Some studies have been reported that doping of nonmetal showed dramatic improvement over undoped TiO2 in its optical absorption and photocatalytic activity under visible light. Asahi et al. theoretically calculated the band structure of the N doped TiO2 and concluded that the visible light sensitivity was due to the narrowing of the band gap by mixing the N2p and O2p states (2,6,7) An additional contribution to the impedance arises from the larger scale microstructural elements, such as grain boundaries and remote electrical contacts. From the analysis of impedance data, relaxation processes at the tip surface junction, grain boundaries, and electrodes can be difierentiated according to characteristic time constants (8,9) Combination of this analysis with spatially resolved impedance imaging yields frequency, bias, and position dependent information on microscopic transport properties. In this paper, the BCN doped TiO2 with nanostructured fllm was fabricated by co deposit method.The structure was studied by X ray difiraction measurement. The microstructure was observed by XPS. The investigation of ac impedance spectra for BCN doped TiO2 thin fllm was performed. The resistance and impedance value in deferent frequency for the thin fllm were determined from impedance technique. 2. SECTION 1 2.1. Experimental Procedure The preparation of TiOBCN includes the use of the precursors Ti(OH)4 and BCN, and subsequent calcination. Detailed procedures are described below. The Ti(OH)4 was prepared by precipitation as described below. The 0.005mol TiCl4 solution was cooled down i10 C below in ice water. Then, 28mL of H2O2 solution (30% was dropped under constant stirring to obtain a transparent, complex compound. Next, a strong NH3 H2O aqueous solution (25% was added dropwise into the transparent yellow precursors resulting in a pH of 10. The transparent yellow precursors were heated to 50 C under constant stirring to a obtain yellow precipitate, which was then flltered, thoroughly washed with distilled water and dried overnight at 70 C. Finally, the prepared Ti(OH)4 was calcined at 400 C for 4h to yield TiO2. Graphite BCN powder was synthesized by high temperature anneals. The resulting Ti(OH)4 and BCN were mixed thoroughly at a mass ratio 10 1. This mixture was then calcined at 400 for 4h for the synthesis of TiOBCN, then added some binder to the TiOBCN power formed fllm. 2.2. Results and Discussion The crystalline phases of the prepared samples were measured by X ray difiraction (XRD) using a Rigaku D/Max III. V X ray difirac tometer with Cu Kfi radiation (1.5406 " at 40kV and 40mA and a secondary graphite monochromator. Measurements were recorded in steps of 0.025 with a count time of 2s in the 2u range of 20 {70 Fig. 1 shows XRD patterns of the synthesized
author_names: Ling Zhang

Yongfan Zhang

Liangguo Yan

Fangxin He
title: Investigation of the Electrical Properties of BCN codoped TiO2 Thin Film Using Impedance Spectroscopy
year: 2011

abstract: Abstract With the development of clean and renewable energy, hydrogen produced via photoelectrochemical (PEC) water splitting has attracted considerable attention. However, to develop the photoanodes with stable and excellent PEC ability is still a big challenge. In our work, TiO 2 nanorods decorated with boron doped g C 3 N 4 (BCN/TiO 2 is fabricated via thermal polymerization method to improve the PEC performance. The BCN/TiO 2 displays 4 fold increase of the photocurrent density (1.01 mA cm 2 at 1.23 V vs. RHE under irradiation (100 mW cm 2 AM 1.5 G) And the onset potential of BCN/TiO 2 exhibits a negative shift with 100 mV. Attributed to the broad light absorption of BCN and hetero junction forming between BCN and TiO 2 the IPCE value is increased to 87.8% in 380 nm, and the charge separation and transfer efficiency are both increased. Doping metal free inorganic material with heteroatoms is a simple and efficient strategy to increase the light absorption within visible light and charge transfer efficiency in PEC and photocatalytic applications.
author_names: Kong Weiqian

Xiaofang Zhang

Binbin Chang

Yannan Zhou

Shouren Zhang

He Guangli

Bao-cheng Yang

Junjie Li
title: Fabrication of B doped g C3N4/TiO2 heterojunction for efficient photoelectrochemical water oxidation
year: 2018

abstract: Abstract The establishment of ultrasensitive, highly selective and cost effective photoelectrochemical (PEC) biosensing platforms is essential for biological assays. In this work, a novel visible light driven PEC platform was developed for ultrasensitive detection of bisphenol A (BPA) based on TiO2 nanoparticles embedded in borocarbonitrides nanosheets (TiO2/BCN) which were fabricated through one step thermal treatment approach. The introduction of BCN not only extends photoresponding of TiO2 to visible light area, but also effectively suppresses the recombination of photoinduced electron hole pairs, and then presented enhanced PEC performances. The PEC sensing platform is constructed via a stepwise modification method with the aids of BPA aptamer, and characterized by PEC and electrochemical impedance spectroscopy (EIS) In the presence of BPA, the photocurrent can be greatly enhanced because BPA can inhibit the recombination of photogenerated electron hole pairs and accelerate the interfacial charge transfer process. The results demonstrated that the photocurrent is highly linear over BPA concentrations ranging from 0.1 fM to 5 nM with a low detection limit of 0.03 fM (S/N 3) Moreover, the as fabricated PEC sensor exhibited high selectivity and low cost, which could be successfully applied for the fast, sensitive, and selective determination of BPA in real water samples.
author_names: Ding Jiang

Xiaojiao Du

Lei Zhou

Henan Li

Kun Wang
title: TiO2 nanoparticles embedded in borocarbonitrides nanosheets for sensitive and selective photoelectrochemical aptasensing of bisphenol A
year: 2018

abstract: Abstract It can be said that energy depletion and environmental pollution on a global scale are the most serious and urgent issues facing mankind in recent times. It is, thus, vital to design novel energy production and conversion systems that utilize natural energy and allow sustainable development without environmental destruction or pollution. In line with these objectives, the decomposition of H2O into H2 and O2, as well as the related reactions using visible light responsive photocatalysts under sunlight irradiation, has been intensively investigated as one of the most promising environmentally benign energy production systems to address these issues. In the past half century, research on various photocatalytic systems using metal oxides has been carried out. However, to achieve higher efficiency in the production of H2, more innovative breakthroughs in the development of photocatalytic materials are strongly desired. To address such issues, graphitic carbon nitride (g C3N4) and hexagonal boron carbon nitride (BCN) nano materials have been investigated as promising visible light responsive photocatalytic materials. In this chapter, we have highlighted the development of such g C3N4 and hexagonal BCN photocatalytic nano materials, focusing on their design, construction and optimization, as well as their applications to environmentally benign solar energy conversion systems, for the decomposition of H2O, reduction and fixation of CO2, and organic redox reactions. Such visible light responsive photocatalytic materials are considered to be the most important research for the development of safe and clean energy production technologies for the 21st century and beyond.
author_names: Bo Wang

Masakazu Anpo

Xinchen Wang
title: Visible Light Responsive Photocatalysts From TiO2 to Carbon Nitrides and Boron Carbon Nitride
year: 2018

abstract: Abstract BCN TiO2 was prepared by doping TiO2 with graphite like structure BCN, and characterised by X ray diffraction (XRD) X ray photoelectron spectroscopy (XPS) scanning electron microscope (SEM) and visible light photocatalysis visible light degradation of MB. The results demonstrated that BCN TiO2 has weaker anatase crystal characteristic peaks, and the crystal size become smaller. XPS result showed that B, C, N have been dopped in crystal lattice of TiO2. Boron was in the form of Bx+ Carbon substituted some of the lattice oxygen atoms as Ti C, and Nitrogen was in the form of Ti N and Ti O N. According to the result of visible light photocatalysis, with BCN dopped in, the catalysts photocatalytic efficiency is greatly improved.
author_names: Ling Zhang

Ling Li

Mou Zonggang

Xifeng Li
title: Study on microstructure and catalytic performance of B, C, N co dopped TiO2
year: 2012