SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Huixing Yang,Wei Li,Yangyang Jiang,Qiuming Wei,Linlin Hou,Zhiliang Wu,Qinyu He,Yinzhen Wang,Dingyuan Tang
The proper design of photocatalysts is essential to improving photocatalytic decomposition of water and degradation of pollutants. In this work, we used nitrogen-rich carbon nitride with high electronic properties combined with CdS-DETA to generate CdS-DETA@g-C 3 N 5 composite, and diethylenetriamine (DETA) was used to enhance the band bending to enable the excellent photocatalytic performance of the photocatalyst. The hydrogen evolution rate (14.23 mmol/(g·h)) of the CdS-DETA@g-C 3 N 5 composite is 7.1, 7.5, and 4.5 times higher than that of g-C 3 N 5 (2.03 mmol/(g·h)), 20CSCN5 (1.89 mmol/(g·h)), and CdS-DETA (3.17 mmol/(g·h)), and the OFLX degradation rate (95.6 %) is 3.4 and 1.5 times higher than that of g-C 3 N 5 and CdS-DETA, respectively. These performance enhancements result from the enhancement of energy band bending, the construction of a built-in electric field (IEF), and the retention of high redox carriers. This work provides new insights into the design of nitrogen-rich carbon nitride-based photocatalyst for efficient photocatalytic degradation and hydrogen precipitation activity.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Electronic Materials
·
2017
·Vol. 3
·期 11
·1700136
·
IF 4.193
Panlong Zhang,Shuai Zhao,Haibo Wang,Jidong Zhang,Jianwu Shi,Hua Wang,Donghang Yan
There is still a challenge in organic electronics to effectively tailor interfacial electronic structures for achieving desired electronic properties for optoelectronic devices. This study realizes the tuning of interfacial electronic structures in organic semiconductor pentacene by employing substrates with different work functions. Pentacene layers show downward band-bending with a low work function, flat band with a middle work function, and upward band-bending with a high work function. The formation of band-bending is explained by the electrostatic potential according to the Fermi level position. Different interfacial electronic structures can influence the carrier transport across the interface. Their diodes show different rectifying behaviors due to band-bending, and ohmic transport is observed for the flat band structure. This work is a promising exploration to realize desired functions of semiconductor devices by tailoring interfacial electronic structures.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Kexin Wang,Zhongge Luo,Bin Xiao,Tong Zhou,Jianhong Zhao,Congcong Shen,Dequan Li,Zhishi Qiu,Jin Zhang,Tianwei He,Qingju Liu
TiO 2 photocatalysts are of great interest in the fields of environmental purification, new energy and so on, because of their non-toxicity, high stability, high redox ability and low cost. However, the photogenerated carriers are severely recombined, which limits the application of TiO 2 photocatalysts. Herein, S-scheme Cu 3 P/TiO 2 heterojunction composites were successfully synthesized by a simple and efficient microwave hydrothermal method, and the results show that the hydrogen production rate of Cu 3 P/TiO 2 is 5.83 mmol∙g −1 ∙h −1 under simulated sunlight irradiation, which is 7.3 and 83.3 times higher than that of pure TiO 2 and Cu 3 P, respectively. This excellent performance is derived from the internal electric field (IEF) and energy band bending generated by the S-scheme heterojunction formed between Cu 3 P and TiO 2 . The density functional theory (DFT) calculation indicates that the Cu 3 P possess smaller work function and more negative conduction band (CB) position than that of TiO 2 , which is very conducive to greatly improve the H + reduction ability and hydrogen production performance. This work provides a new idea for the reveal of electron transfer paths and active sites in S-scheme heterojunctions and deepens the mechanism understanding.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Energy & Environmental Materials
·
2023
·
IF 15
Zhaorui Wen,Chao Liang,Shengwen Li,Gang Wang,Bingchen He,Hao Gu,Junpeng Xie,Hui Pan,Zhenhuang Su,Xingyu Gao,Guo Hong,Shi Chen
Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites. However, their incomplete passivation and chaotic usage amounts are not conducive to the preparation of high-quality perovskite films. Herein, we succeeded in obtaining higher-quality CsPbBr 3 films by introducing large-area monolayer graphene as a stable physical overlay on top of TiO 2 substrates. Benefiting from the inert and atomic smooth graphene surface, the CsPbBr 3 film grown on top by the van der Waal epitaxy has higher crystallinity, improved (100) orientation, and an average domain size of up to 1.22 μm. Meanwhile, a strong downward band bending is observed at the graphene/perovskite interface, improving the electron extraction to the electron transport layers (ETL). As a result, perovskite film grown on graphene has lower photoluminescence (PL) intensity, shorter carrier lifetime, and fewer defects. Finally, a photovoltaic device based on epitaxy CsPbBr 3 film is fabricated, exhibiting power conversion efficiency (PCE) of up to 10.64% and stability over 2000 h in the air.
研究领域:
材料科学
·
光伏技术
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
Energy & Environmental Science
·
2017
·Vol. 10
·期 11
·2401-2410
·
IF 29.518
Ya-Fang Qi,Dong-Xing Kou,Wen-Hui Zhou,Zheng-Ji Zhou,Qing-Wen Tian,Yue-Na Meng,Xin-Sheng Liu,Zu-Liang Du,Si-Xin Wu
Although the substitution of Cu by Ag to suppress CuZn defects offers several advantages in overcoming the large open-circuit voltage (Voc) deficit for Cu2ZnSn(S,Se)4 (CZTSSe) solar cells, an excellent performance has not been achieved to date primarily due to the Fermi level pinning at the CdS/absorber interface and large recombination at the absorber/Mo interface. Herein, we developed a composition grading strategy to achieve a V-shaped Ag-graded structure with a higher Ag content on both the back and front surfaces of the (Cu,Ag)2ZnSn(S,Se)4 (CAZTSSe) layer. The key advantages of this Ag-graded structure are as follows: the higher content towards the CdS/absorber interface can create weak n-type donor defects and retard Fermi level pinning, whereas the lower content at the interlayer maintains the conductivity and light absorption; moreover, the other higher content towards Mo back contact can effectively suppress the recombination and improve the utilization of long-wave incident light. By appropriately adjusting the Ag gradient, we demonstrated a significant increase in Voc, and an unexpected conversion efficiency of 11.2% was achieved. This is the highest efficiency achieved to date for Ag-substituted CZTSSe solar cells, and the result supports a new aspect that synthesis of a composition-graded CAZTSSe absorber has great potential for future research.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2024
·
IF 5.8
Jingwen Sun,Shangling Han,Fanglei Yao,Ruixin Li,Chenchen Fang,Xiaoyuan Zhang,Yaya Wang,Xuefeng Xu,Di Wu,Kai Liu,Pan Xiong,Junwu Zhu
Construction of built-in electric field has been identified as an attractive improvement strategy in terms of photoelectrochemical (PEC) water splitting by facilitating the carriers extraction from the inside to the surface. However, the promotion effect of the electric field is still restrained by the confined built-in area. Herein, we construct a microscale built-in electric field via the gradient oxygen doping. Octahedral configuration of the synthesized CdIn2S4 (CIS) behaves as a structural basis, which enables the subsequent oxygen doping poking to the depth of ~100 nm. Accordingly, oxygen doped CIS (OCIS) photoanode exhibits a microscale built-in electric field with the band bending. An excellent PEC catalytic activity with a photocurrent density of 3.69 mA/cm2 at 1.23 V vs RHE is achieved by OCIS, which is 3.1 times higher than that of CIS. Combining the results of sufficient characterizations and theoretical calculation, accelerating migration and separation of charge carriers has been determined as the essential encouragement. Meanwhile, probable recombination risk at the doping centers has also been reduced to the minimum via optimal experiments. This work provides a new generation idea of build-in electric field from the view point of bulky configuration towards PEC water splitting.
研究领域:
材料科学
·
光电化学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advances in Materials Science and Engineering
·
2018
·Vol. 2018
·期 1
·7252809
·
IF 1.372
Van-Tuan Mai,Quang-Bac Hoang,Xuan-Dung Mai
Cost-effective methods for preparing ZnO nanostructures are of importance for the deployment of ZnO in many applications including n-type conduits, catalysts, nanophosphor, and optoelectronics. Herein, we present a room-temperature sol-gel method with the aid of ultrasonication to prepare white-emitting ZnO nanoparticles (NPs). X-ray diffraction and electron microscopic analyses revealed that the size and shape of ZnO NPs can be controlled simply by changing the concentration of the Zn precursor. The ZnO NPs had a broad photoluminescence emission, ranging from 450 nm to 800 nm, while their composite in PMMA matrix showed an enhancement in the red region induced by ZnO-PMMA interfacial band-bending effects. The results demonstrated herein promise a simple tool for control over size, shape, and emission of ZnO materials for diverse applications.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
高分子化学
·
发光材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 42
·22292-22301
·
IF 11.301
Junjie Fu,Dongxing Kou,Wenhui Zhou,Zhengji Zhou,Shengjie Yuan,Yafang Qi,Sixin Wu
A major obstacle hindering further development of kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells is the inherent recombination losses that occur both via bulk defects and charge extraction interfaces. Herein, we propose a generic Ag, Ge dual-gradient absorber architecture, involving a downshift of absorber VBM at the front contact and an upshift of absorber CBM at the back contact, to improve device performance. We experimentally show that the substitution of Cu by Ag allows for larger band bending at the p–n junction, and the substitution of Sn by Ge imposes an additional drift field within the quasi-neutral region. Additionally, the Ag and Ge ions diffusing into the bulk absorber passivate the deleterious CuZn and CuSn deep-level defects. In turn, accelerated charge extraction, transport and minimized recombination loss offered surprising gains in Voc and Jsc, and the dual-gradient device achieved a maximum efficiency of 12.26% with an improved Voc,deficit of 553 mV. This Ag, Ge graded-substitution approach offers an alternative absorber architecture to improve the Voc,deficit in future high-efficiency kesterite PV cells.
研究领域:
材料科学
·
光伏技术
·
半导体物理
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2019
·Vol. 31
·期 12
·1806725
·
IF 25.809
Fengren Cao,Linxing Meng,Meng Wang,Wei Tian,Liang Li
Self-powered photodetectors are highly desired to meet the great demand in applications of sensing, communication, and imaging. Manipulating the carrier separation and recombination is critical to achieve high performance. In this paper, a self-powered photodetector based on the integrated gradient O-doped CdS nanorod array and perovskite is presented. Through optimizing the degree of continuous built-in band bending in the gradient-O CdS, the photodetector demonstrates a remarkable detectivity of 2.1 × 10 13 Jones. Under the self-powered voltage mode, the responsivity can be as high as 0.48 A W −1 , and the rise and decay time are 0.54/2.21 ms. The comprehensive performance is comparable and even better than reported perovskite and other types of self-powered photodetectors. The improved mechanism reveals that the gradient band bending promotes the photogenerated carrier transfer and hinders the recombination at the interface.
研究领域:
光电子学
·
材料科学
·
纳米技术
·
半导体物理
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Meiqin Xiao,Simin Gong,Jonghee Yang,Yi Wang,Junyu Nie,Wenzhe Li,Jiang Cheng,Hongkang Xu,Wei Zhang,Junzhong Wang,Ping Chen
Ion migration, especially taking place at the interface of perovskite/charge transport layer, poses great threats to the stability of perovskite light–emitting diodes (PeLEDs). However, the existing strategies mitigating ion migration sacrifice efficient charge injection, thus limiting the PeLED performances. Herein, an interfacial layer of a biaxially charge-polarized molecule, bi-4-(N-carbazolyl)phenyl)phenylphosphine oxide (BCPO), is applied. The strong surface coordination of BCPO not only manifests a high-quality metal halide perovskites (MHPs) emitter with improved defect passivation and crystallinity but also establishes a rigorous vertical dipole alignment, inducing band-bending for favorable electron injection. Additionally, the in-plane geometry of the electron-withdrawing carbazolylphenyl units achieves intimate lateral electrostatic contact with the MHPs surface, realizing stronger chemical interaction that suppresses the escape of halide at the interface. Encouraged by these achievements, the optimized PeLEDs with BCPO demonstrate maximum external quantum efficiency of 25.8% and T 50-EL lifetime of 13.4 h, representing one of the best green PeLEDs reported. This work newly opens a synergistic strategy, combined with molecular structure design and interfacial engineering, for simultaneously realizing efficient and color-stable PeLEDs, which tackles the crucial challenges for their commercialization.
研究领域:
材料科学
·
光电子学
·
纳米技术
·
分子工程
·
器件物理
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2019
·Vol. 10
·期 1
·1-11
·
IF 11.878
Zhu Cheng,Niu Xiuxiu,Fu Yuhao,Li Nengxu,Hu Chen,Chen Yihua,He Xin,Na Guangren,Liu Pengfei,Zai Huachao,Ge Yang,Lu Yue,Ke Xiaoxing,Bai Yang,Yang Shihe,Chen Pengwan,Li Yujing,Sui Manling,Zhang Lijun,Zhou Huanping,Chen Qi
The mixed halide perovskites have emerged as outstanding light absorbers for efficient solar cells. Unfortunately, it reveals inhomogeneity in these polycrystalline films due to composition separation, which leads to local lattice mismatches and emergent residual strains consequently. Thus far, the understanding of these residual strains and their effects on photovoltaic device performance is absent. Herein we study the evolution of residual strain over the films by depth-dependent grazing incident X-ray diffraction measurements. We identify the gradient distribution of in-plane strain component perpendicular to the substrate. Moreover, we reveal its impacts on the carrier dynamics over corresponding solar cells, which is stemmed from the strain induced energy bands bending of the perovskite absorber as indicated by first-principles calculations. Eventually, we modulate the status of residual strains in a controllable manner, which leads to enhanced PCEs up to 20.7% (certified) in devices via rational strain engineering.
研究领域:
材料科学
·
光伏技术
·
固体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Hai Guo,Huai-Yuan Niu,Chao Liang,Cheng-Gang Niu,Yu Liu,Ning Tang,Yang Yang,Hui-Yun Liu,Ya-Ya Yang,Wen-Jun Wang
In this work, electron-withdrawing groups functionalized few layer graphitic carbon nitride (FCN-12) nanosheet was prepared and utilized for photocatalytic activation of peroxymonosulfate (PMS). Experimental characterization and density functional theory (DFT) calculation reveals that the electronic structure of FCN-12 is efficiently adjusted by forming an upward band bending, as the functionalized carbonyl (C=O) and carboxyl (-COOH) groups can withdraw the electron from the C-N=C skeleton. With the addition of PMS, FCN-12 displays superb photocatalytic activity for chlortetracycline hydrochloride (CTC) degradation, where 83.4% CTC can be degraded within 120 min under visible light irradiation, much higher than that of bulk g-C 3 N 4 (34.3%). Besides, even under the different pH condition and co-existed anions environment, FCN-12/PMS/vis system still exhibits favorable applicability. The boosted catalytic performance is resulted from the collective effect of the few-layer feature and the energy band bending, which leads to the effective migration of photogenerated electron from FCN-12 to PMS via C=O and -COOH groups. This work not only provides an exhaustive insight into the role of energy band bending in electron-withdrawing group functionalized g-C 3 N 4 , but also paves the avenue for the development of metal-free photocatalyst-mediated environmental remediation based on PMS activation.
研究领域:
环境科学
·
材料科学
·
化学
·
光催化
✓ 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）