通讯机构：
[Tang, Yiwen] C;Cent China Normal Univ CCNU, Dept Nanosci & Technol, Coll Phys & Technol, Wuhan 430079, Peoples R China.
关键词：
defect states;voltage loss;n-type doping;photovoltage;perovskite solar cells
摘要：
The state-of-the-art perovskite solar cells (PSCs) with SnO(2) electron transporting material (ETL) layer displays the probability of conquering the low electron mobility and serious leakage current loss of the TiO(2) ETL layer in photoelectronic devices. The rapid development of SnO(2) ETL layer has brought perovskite efficiencies >20%. However, high density of defect states and voltage loss of high temperature SnO(2) are still latent impediment for the long-term stability and hysteresis effect of photovoltaics. Herein, Nb(5+) doped SnO(2) with deeper energy level is utilized as a compact ETL for printable mesoscopic PSCs. It promotes carrier concentration increase caused by n-type doping, assists Fermi energy level and conduction band minimum to move the deeper energy level, and significantly reduces interface carrier recombination, thus increasing the photovoltage of the device. As a result, the use of Nb(5+) doped SnO(2) brings high photovoltage of 0.92 V, which is 40 mV higher than that of 0.88 V for device based on SnO(2) compact layer. The resulting PSCs displays outstanding efficiency of 13.53%, which contains an ∼10% improvements compared to those without Nb(5+) doping. Our study emphasizes the significance of element doping for compact layer and lays the groundwork for high efficiency PSCs.
关键词：
Carbon-based perovskite solar cells;Energy-level matching;Inorganic copper phthalocyanine;Phenethylammonium iodide treatment;Stability
摘要：
Defects caused by the structural disorder of perovskites and voltage loss resulting from mismatched band structure are important issues to address to improve the performance of carbon-based perovskite solar cells. Different from the conventional approaches of additive-based passivation of perovskite precursors and introducing a hole-transport layer between the perovskite layer and carbon electrode, herein we report a defect-healing method using phenethylammonium iodide (PEAI) treatment and band-structure modification using high-work-function inorganic copper phthalocyanine (CuPc). Because of its relatively smoother surfaces and lower defect content, the optimized device after PEAI-based passivation of the perovskite achieves a power conversion efficiency (PCE) of 11.74%. The PCE is further raised to 13.41% through the auxiliary energy-level matching and high hole extraction abilities of the CuPc-modified carbon electrode. The best-performing device exhibits excellent moisture tolerance and thermal stability with minor current density-voltage hysteresis.
摘要：
Creating a hybrid cobaltous-based oxide/sulfide core-shell composite is an effective strategy to improve the composites conductivity thus enhance the electrochemical performance of cobaltous oxide. By using Co3O4 nanosheets (NSs) as precursor, a room-temperature sulfurization for obtaining Co3O4/CoS core-shell NSs via anion exchange is developed which show better supercapacitor performance in contrast to the most high-temperature material process required in synthesis of CoS. The study demonstrates that the preceding step of introducing oxygen vacancies to Co3O4 by NaBH4 solution reduction is crucial, which allows S2- to facilitate entering the position of O2- in the solid phase successfully at room temperature. The as-obtained Co3O4/CoS NSs preserve the porous morphology and have larger accessible active surface area and better conductivity than those of Co3O4 and CoS composite. In this report, the Co3O4/CoS NSs exhibit an improved specific capacitance of 1658 F g(-1) at 1 A g(-1) which can be maintained at 92.3% after 10,000 cycles. The corresponding assembled asymmetric supercapacitor with activated carbon as anode displays a high energy density of 23.6 Wh kg(-1) at a power density of 250 W kg(-1). (C) 2019 Elsevier B.V. All rights reserved.
通讯机构：
[Tang, Yiwen] C;[Hu, Yue] H;Cent China Normal Univ CCNU, Coll Phys & Technol, Dept Nanosci & Technol, Wuhan 430079, Peoples R China.;Huazhong Univ Sci & Technol HUST, Wuhan Natl Lab Optoelect WNLO, Michael Gratzel Ctr Mesoscop Solar Cells MGC, Wuhan 430074, Peoples R China.
摘要：
The all-inorganic CsPb(IxBr1-x) 3 (0 <= x <= 1) perovskite solar cells (PSCs) are attractive by virtue of their high environmental and thermal stability. Nevertheless, multiple-step deposition and high annealing temperature (>250 degrees C) and the structural and optoelectronic properties changes upon temperature-dependent phase-transition are potential impediments for highly efficient and stable PSCs. Herein, a space-confined method to fabricate stable lower-order symmetric pure monoclinic CsPbBr3 phase at low temperature (<50 degrees C) is for the first time reported. It is found that the carbon-based mesoporous fully printable area can inhibit the phase transition to get a pure phase. Therefore, the device exhibits a power conversion efficiency of 7.52% with a low hysteresis index of 0.024. Moreover, the device passed the 1000 h 85 degrees C thermal test and the 200 cycles thermal cycling test according to IEC-61625 stability tests. These are critical progresses for achieving long-term stability and the stable pure inorganic perovskite phase of high-performance photovoltaics.
通讯机构：
[Tang, Yiwen] C;[Yuan, N; Li, MY] W;Wuhan Univ, Sch Phys & Technol, Key Lab Artificial Micro Nano Struct, Minist Educ, Wuhan 430072, Peoples R China.;Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Hubei, Peoples R China.
关键词：
Au nanoparticles;Dye-sensitized solar cells;Gradient-ascent architecture scattering;Localized surface plasmon resonance;SiO2@[email protected]2 microspheres
摘要：
Highly homogeneous, well dispersed SiO2@Au@TiO2(SAT) microspheres decorated with Au nanoparticles (AuNPs) were prepared and incorporated into the photoanode with an optimized concentration gradient-ascent. The effects of SAT microspheres and the gradient-ascent architecture on the light absorption and the photoelectric conversion efficiency (PCE) of the dye-sensitized solar cells (DSSCs) were investigated. Studies indicate that the introduction of SAT microspheres and the gradient-ascent architecture in the photoanode significantly enhance the light scattering and harvesting capability of the photoanode. The DSSC with the optimized SAT gradient-ascent photoanode has the maximum short circuit current density (J(sc)) of 17.7 mA cm(-2) and PCE of 7.75%, remarkably higher than those of the conventional DSSC by 23.7% and 28.0%, respectively. This significantly enhancement of the performance of the DSSC can be attributed to the excellent light reflection/scattering of SAT, the localized surface plasma resonance (LSPR) effect of AuNPs within the microspheres, and the gradient-ascent architecture of SAT microspheres inside the photoanode. This study demonstrates that the tri-synergies of the scattering of SAT microspheres, the LSPR of AuNPs and the gradient-ascent architecture can effectively improve the PCE of DSSC. (C) 2019 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
摘要：
Graphene-based materials have potential applications in supercapacitors, owing to their unique twodimensional structure, high surface area, remarkable chemical stability, and outstanding electrical conductivity. In this work, Hummers method was used to prepare graphene oxide, and then in situ electrochemical method was firstly used to deposit graphene nanosheets on Co/CoO core-shell nano-structure to form a sandwich-type of Co/CoO/graphene electrode materials. The effect of electro-deposition graphene cycles on the electrochemical properties of Co/CoO/graphene composite were investigated. The results showed that the coating of graphene on Co/CoO further enhanced the conductivity of the material, and the specific capacitance reached 7.765 F cm(-2) at the current density of 1 mAcm(-2). The Co/CoO/graphene and AC were assembled into an asymmetric supercapacitor. After 10000 charge/discharge cycles, the total capacitance of the asymmetric supercapacitor was still maintained 79.9%. The coating of graphene not only increased the conductivity of the material, but also increased the stable of structure. (C) 2019 Elsevier B.V. All rights reserved.
作者机构：
[Tang, Yiwen; Du, Heping; Zhang, Jing; Wang, Shiyu; Shen, Wenjian] Cent China Normal Univ, Coll Phys & Technol, Inst Nanosci & Technol, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Tang, Yiwen] C;Cent China Normal Univ, Coll Phys & Technol, Inst Nanosci & Technol, Wuhan 430079, Hubei, Peoples R China.
关键词：
Chemical bath deposition;Interface passivation layer;Ion-exchange;Quantum dots-sensitized solar cells;ZnS-MnS composites
摘要：
Interface passivation layer deposited onto photoanodes has been proven to be an available way to suppress charge recombination and enhance the power conversion efficiency in quantum dot-sensitized solar cells. In this work, the ZnS-MnS composites layers inserted in ZnO/CdS nanotubes photoanodes interface is firstly fabricated via ion-exchange and chemical bath deposition methods, simultaneously. By inserting the ZnS-MnS composites, electron back transfer is efficiently hindered. In addition, the uniform ZnS-MnS layer effectively blocks the direct contact between the polysulfide electrolyte and ZnO nanotubes, which inhabits the recombination of electron-hole pairs occurred at the interface. Besides, the MnS layer is in favour of the CdS quantum dots in higher load, profiting the light absorption intensity in the visible light region. Thus ZnO/ZnS-MnS/CdS nanotubes quantum dot-sensitized solar cells have efficiency of 3.62%, which is much higher than that of the solar cell with ZnS passivation layer (2.33%). This work demonstrates that constructing ZnS-MnS interface passivation layer with a proper band gap structure is a promising approach to enhance the performance of quantum dot-sensitized solar cells. (C) 2019 Elsevier B.V. All rights reserved.
作者机构：
[Wu, Hua; Wen, Junqing; Sun, Ruijuan; He, Wanlin; Bai, Lihua] Xian Shi You Univ, Sch Sci, Xian 710065, Shaanxi, Peoples R China.;[Tang, Yiwen] Cent China Normal Univ, Sch Phys Sci & Technol, Wuhan 430079, Hubei, Peoples R China.;[Zhang, Han; Wang, Xiao] Xidian Univ, Sch Microelect, State Key Discipline Lab Wide Band Gap Semicond T, Xian 710071, Shaanxi, Peoples R China.
通讯机构：
[Tang, Yiwen] C;[Bai, Lihua] X;Xian Shi You Univ, Sch Sci, Xian 710065, Shaanxi, Peoples R China.;Cent China Normal Univ, Sch Phys Sci & Technol, Wuhan 430079, Hubei, Peoples R China.
关键词：
Au-nanorods;composite photoanodes;dye sensitized solar cells (DSSCs);grapheme;SiO2@TiO2 double shells;synergistic effect
摘要：
Graphene and Au nanorods (AuNRs) coated with SiO2@TiO2 double shells (AuNR@SiO2@TiO2) were incorporated to form novel composite photoanodes in dye sensitized solar cells (DSSCs). The performances of the photoanodes and DSSCs are studied systematically. The short circuit current density (J sc) and power conversion efficiency (PCE) of these composited DSSCs were greatly enhanced and the influences of the graphene, AuNRs and the SiO2@TiO2 double shells were revealed. The optimal properties with the maximal J sc of 16.26 mA cm(-2) and PCE of 8.08% are obtained in the DSSC co-doped with graphene and AuNR@SiO2@TiO2, significantly higher than those of the conventional DSSC with pure TiO2 photoanode by 37.7% and 32.9%, respectively. These significant enhancements in J sc and PCE are attributed to the synergistic effect of graphene, the local surface plasma resonance of AuNRs, as well as the outer SiO2@TiO2 double shells, which result in the increased specific surface area and dye adsorption, the increased light absorption, the decreased charge transfer resistance R 2 and electron recombination and thus the increased J sc and PCE of the DSSCs.
通讯机构：
[Yiwen Tang] N;[Yue Hu] M;Michael Grätzel Center for Mesoscopic Solar Cells (MGC), Wuhan National Laboratory for Optoelectronics (WNLO), Huazhong University of Science and Technology (HUST), Wuhan 430074, China<&wdkj&>Nano-Science & Technology, College of Physics and Technology, Central China Normal University (CCNU), Wuhan 430079, China
摘要：
A low-temperature carbon electrode with good perovskite compatibility is employed in hole-transport-material free perovskite solar cells, and a champion power conversion efficiency (PCE) of 11.7% is obtained. The PCE is enhanced to 14.55% by an interface modification of PEDOT:PSS. The application of this carbon on ITO/PEN substrates is also demonstrated.
作者机构：
[Su, Chenliang; Li, Ying; Tian, Bingbing; Qu, Gan] Shenzhen Univ, Coll Optoelect Engn, SZU NUS Collaborat Ctr, Shenzhen 518060, Peoples R China.;[Su, Chenliang; Li, Ying; Tian, Bingbing; Qu, Gan] Shenzhen Univ, Int Collaborat Lab Mat Optoelect Sci & Technol 2D, Engn Technol Res Ctr Mat Informat Funct Devices &, Coll Optoelect Engn, Shenzhen 518060, Peoples R China.;[Tang, Yiwen; Qu, Gan] Cent China Normal Univ, Dept Phys & Technol, Inst Nanosci & Technol, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Tang, Yiwen] C;[Li, Ying] S;Shenzhen Univ, Coll Optoelect Engn, SZU NUS Collaborat Ctr, Shenzhen 518060, Peoples R China.;Shenzhen Univ, Int Collaborat Lab Mat Optoelect Sci & Technol 2D, Engn Technol Res Ctr Mat Informat Funct Devices &, Coll Optoelect Engn, Shenzhen 518060, Peoples R China.;Cent China Normal Univ, Dept Phys & Technol, Inst Nanosci & Technol, Wuhan 430079, Hubei, Peoples R China.
摘要：
Herein, gas bubbles generated in situ from precursors assist the rapid construction of hollow sycamore fruit-like CoMoO4 spheres (HSCSs). This bubble-assisted fabrication strategy is easy to operate, ultra-fast, low cost and post-treatment-free, showing great potential for the large-scale production of HSCSs. The growth mechanism of HSCSs is discussed to reveal the evolution process, which may be generalized to the construction of a series of hollow ternary Mo-based oxides. The obtained HSCSs exhibit a superior specific capacitance and outstanding cyclic stability when applied in supercapacitors.
