JOURNAL OF ALLOYS AND COMPOUNDS
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2020
·
IF 4.65
Yeming Mei,Hongli Liu,Xianggao Li,Shirong Wang
Hollow TiO 2 spheres were synthesized by template method, with the diameters was 200 nm and the thickness of shell about 30 nm. The high-quality perovskite films fabricated on the hollow TiO 2 mesoporous layer demonstrate smooth surface and large grain size, resulting in the better scattering light ability and fewer defects. The efficiency of the perovskite solar cells prepared on hollow mesoporous layer can reach 17.60%, which is an approximately 14% higher than the PCE of conventional mesoporous layer devices under the same condition. Importantly, the solar cells with hollow TiO 2 can exhibit better stability than the cells with mesoporous TiO 2 after aging 30 days in 65% relative humidity under dark conditions. The results indicate that the hollow TiO 2 mesoporous layer will be a candidate for better efficient and stable CH 3 NH 3 PbI 3 perovskite solar cells, and this structure provides a direction for the design of novel mesoporous layers for perovskite solar cells in future.
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
ADVANCED FUNCTIONAL MATERIALS
·
2021
·Vol. 31
·期 36
·2103949
·
IF 18.808
Liangbin Xiong,Jiashuai Li,Feihong Ye,Haibing Wang,Yaxiong Guo,Xing Ming,Qingyun Chen,Shaoan Zhang,Ruihao Xie,Zhanxu Chen,Yang Lv,Guangqi Hu,Yingji He,Guojia Fang
SnO 2 compact layer (c-SnO 2 ) frequently suffers from degradation in high temperature processes (HTP) such as crack, worse interfacial contact, and electrical properties, that is, annealing effect. To solve this problem, a kind of bifunctional SnO 2 colloid is developed by using small molecular oxalate whose organic components can be removed clearly at a low temperature process (LTP). The c-SnO 2 and SnO 2 mesoporous layer (m-SnO 2 ) derived from the fresh and aged sols with the same colloid show no annealing effect, decreasing oxygen vacancy, and adsorbing water on increasing annealing temperature. The champion devices of LTP and HTP SnO 2 planar perovskite solar cells (PSCs) achieve, respectively, stabilized photoelectric conversion efficiencies (PCEs) of 20.74% and 20.70%. In contrast, the performance of champion devices of their mesoporous counterparts is significantly improved, showing nearly hysteresis free character with stabilized PCEs of 22.40% and 22.37%, respectively. The inclusion of m-SnO 2 plays a role of an energy bridge, improving electrons collection efficiency, which is supported by photoluminescence and transient photoluminescence characterizations. HTP SnO 2 mesoporous PSCs can preserve 97.6% and 80% of their initial PCEs after aging for 25 weeks and 8-h irradiated/16-h dark cycle within 104 h. The high stability of HTP SnO 2 PSCs may ascribe to low oxygen vacancy and adsorbed water of HTP SnO 2 .
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
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Jiwei Liang,Huiping Gao,Mengji Yi,Wenjia Shi,Yuefeng Liu,Zhenlong Zhang,Yanli Mao
β-NaYF 4 :Yb 3+ , Tm 3+ @ TiO 2 core-shell upconversion nanoparticles (UCNPs) were synthesized and incorporated into the TiO 2 mesoporous layer of perovskite solar cells (PSCs). Changes of the upconversion spectra of the UCNPs suggest the existence of the electron injection from NaYF 4 :Yb 3+ , Tm 3+ to the conduction band (CB) of TiO 2 through the NaYF 4 :Yb 3+ , Tm 3+ /TiO 2 nano-heterojunctions. The core-shell UCNPs that incorporated into the TiO 2 mesoporous layer not only act as the upconversion centers to use the NIR light but also serve as the light scatter centers to enhance the light harvesting. When using mesoporous layer containing the core-shell UCNPs in PSCs, the efficiency of the best devices is 16.27%, which is about 16.38% higher than that of the devices without core-shell UCNPs (13.98%). The significant enhancement in the performance of the PSCs is attributed to light scattering, NIR light upconversion and electron injection from the UCNPs to the CB of TiO 2 .
研究领域:
材料科学
·
能源科学
·
纳米技术
✓ 已验证
DOI
高影响因子
Nanoscale Research Letters
·
2020
·Vol. 15
·期 1
·1-8
·
IF 3.578
Yu Miao,Sun Haoxuan,Huang Xiaona,Yan Yichao,Zhang Wanli
Recently, reported perovskite solar cells (PSCs) with high power conversion efficiency (PCE) are mostly based on mesoporous structures containing mesoporous titanium oxide (TiO 2 ) which is the main factor to reduce the overall hysteresis. However, existing fabrication approaches for mesoporous TiO 2 generally require a high-temperature annealing process. Moreover, there is still a long way to go for improvement in terms of increasing the electron conductivity and reducing the carrier recombination. Herein, a facile one-step, in situ, and low-temperature method was developed to prepare an Nb:TiO 2 compact-mesoporous layer which served as both scaffold and electron transport layer (ETL) for PSCs. The Nb:TiO 2 compact-mesoporous ETL-based PSCs exhibit suppressed hysteresis, which is attributed to the synergistic effect of the increased interface surface area caused by nano-pin morphology and the improved carrier transportation caused by Nb doping. Such a high-quality compact-mesoporous layer allows the PSCs assembled using optimized 2% Nb-doped TiO 2 to achieve a remarkable PCE of 19.74%. This work promises an effective approach for creating hysteresis-less and high-efficiency PSCs based on compact-mesoporous structures with lower energy consumption and cost.
研究领域:
材料科学
·
光伏技术
·
纳米材料
·
能源化学
·
半导体器件
·
表面工程
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Rangwei Meng,Zhiyuan He,Xuanhui Luo,Chi Zhang,Mengwei Chen,Halfei Lu,Yingping Yang
In this study, NaGdF 4 :Yb 3+ , Er 3+ @NaGdF 4 :Eu 3+ (NGEY@NGE) core-shell rare earth nanoparticles are prepared by a simple hydrothermal method . After testing, the emission peaks are observed at 415, 525, 540 and 660 nm with an excitation light of 980 nm due to the up-conversion luminescence from rare-earth nanoparticles . Under light excitation at 395 nm, the rare-earth nanoparticles undergo down-conversion luminescence with emission peaks at 590, 610 and 695 nm. The resulting nanoparticles are introduced into the TiO 2 mesoporous layer of hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes to broaden the spectral response of the cells from the visible range to the near-infrared and near-ultraviolet regions, which can guarantee a high light absorption efficiency and corresponding accelerated generation of electron-hole pairs. The results suggest that the mixing of NGEY@NGE nanoparticles into mesoporous TiO 2 layer improves the power conversion efficiency of PSCs to 14.21%, which is 10.6% higher than that of the control cells, which can pave an effective way to improve the performance of PSCs with a broadened response range.
研究领域:
材料科学
·
纳米技术
·
太阳能
·
光电
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）