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In this work, we report on the first successful deposition of Vernier phase yttrium oxyfluoride (V-YOF) thin films on Si (100) wafers using pulsed liquid injection metal organic chemical vapor deposition (PLI-MOCVD). The formation of V-YOF has been confirmed by X-ray diffraction measurements and electron probe microanalysis. The infrared phonon modes of V-YOF thin films and their corresponding optical constants as inferred from spectroscopic ellipsometry are reported here for the first time. The V-YOF thin films are featured by a broad absorption band centering around 370–373 cm−1; their refractive index is located between those of YF3 and Y2O3, and which shows an intimate relationship with the oxygen content in the film. The luminescence properties of Er3+ doped V-YOF thin films are finally examined and compared with that of YF3. Our results highlight that the as-deposited V-YOF thin films by PLI-MOCVD serve as promising candidates as efficient host material for spectral conversion for photovoltaic applications. [ABSTRACT FROM AUTHOR]

An effective encapsulation solution for flexible CIGS is urgently needed to ensure a competitive market entry of the technology. In this work, we demonstrate the feasibility to effectively encapsulate module-level (10 × 10 cm2) CIGS/glass solar cells by employing a thin Al 2 O 3 barrier layer grown by atomic layer deposition (ALD). As determined by a direct methodology, 10 nm ALD-Al 2 O 3 is proved to be sufficient in preventing electrical degradation of the Al:ZnO (AZO) window layer upon exposure to damp heat test (DHT) and equally effective to encapsulate 10 × 10 cm2 CIGS/glass mini-modules by efficient blockage of moisture ingress. CIGS mini-modules encapsulated by ALD-Al 2 O 3 barrier layer retain an average of 80% and 72% of initial efficiency after 1000 and 2000 h of DHT, respectively. Whereas unencapsulated modules drop to an average of 67% (1000 h DHT) and 22% (2000 h DHT) of initial efficiency. Thanks to the presence of ALD-Al 2 O 3 barrier layer, less electrical degradation occurred in AZO window layer and P3 interconnection; also less shunting paths appeared – both led to a lower FF drop in encapsulated CIGS mini-modules. However, an issue of Na migration out of the CIGS layer is observed, which negatively impacts the module stability during DHT. Image 1 • ALD-Al 2 O 3 is proved feasible to effectively encapsulate module-level CIGS solar cells. • 10 nm ALD-Al 2 O 3 is comparable to glass-glass encapsulation, especially for >1000h DHT. • ALD-Al 2 O 3 prevents electrical degradation of AZO window layer and P3 interconnection. • Na diffusion out of CIGS during DHT leads to ~10% drop in V oc after 1000h DHT. [ABSTRACT FROM AUTHOR]

Unusual substitutional and interstitial solid solutions were observed in (1−x)Ba(Zr0.35Ti0.65)O3-xZnO thin films, where one Zn2+ cation substituted one B-site Zr4+/Ti4+ site and two Zn2+ cations substituted one A-site Ba2+ site simultaneously. Such a hybrid solid solution with an appropriate ZnO content remarkably increases both the electric breakdown strength (Eb) by widening the bandgap and the energy storage efficiency (η) by suppressing the hysteresis of the ferroelectric loop. As a result, the films with x = 0.2 show superior energy storage performance with a recoverable energy storage density (Wrec) of 130.3 J/cm3 and η of 89.1%. This work confirms the feasibility of forming an unconventional hybrid solid solution, which may shed light on further work on perovskite oxides with improved ferroic functionalities. [ABSTRACT FROM AUTHOR]

• Orientation of Bi 0.9 La 0.1 FeO 3 (BFLO) were controlled by anneal temperature. • (001)-oriented of BLFO (BLFO (001)) has higher photovoltaic performances. • BLFO (001) has obvious domain structure which contributing to stronger polarization. • BLFO (001) exhibits excellent self-powered photodetection properties. Self-powered photodetectors based on ferroelectric photovoltaic materials have attracted a lot of attentions in advanced optoelectronic systems. Because of the opposition between ferroelectric polarization and bandgap, however, low photocurrent output is a serious drawback for their photodetection performances. Here, excellent photodetection properties are achieved in a Bi 0.9 La 0.1 FeO 3 (BLFO (001)) ferroelectric thin film with (001)-orientation growth. Its responsivity and detectivity can reach respectively 3.95 mA/W and 5.058 × 109 Jones under 100 mW/cm2, which are almost 5 and 3 times than those of the Bi 0.9 La 0.1 FeO 3 (BLFO ro) thin film with random orientation. It is suggested that the BLFO (001) thin film with a strong domain structure possesses high polarization, which enhances depolarization field and decreases build-in field (E bi) at Au/BLFO interface, generating a large driving force to separate photogenerated carriers. This work opens up a promising route to the development of high-performance ferroelectric photodetectors. [ABSTRACT FROM AUTHOR]

Cu 2 ZnSnS 4x Se 4(1-x) (CZTSSe) has recently attracted much attention for solar water splitting due to its high absorption efficient and tunable bandgap. However, high quality CZTSSe thin films with good quality and adherence with the substrate are mainly based on physical deposition method, such as magnetron sputtering, which is expensive and energy consuming processes. Here, we have developed a novel and low-cost solution fabrication method and CZTSSe electrodes were synthesized at low temperature by hydrothermal treatment of chemical bath deposited SnS films. The quality and phase purity of CZTSSe thin films were greatly improved after annealing process and the effect of SnS thickness to the physical and photoelectrochemical (PEC) properties of CZTSSe thin films were detailedly studied. The fabrication of FTO/CZTSSe/CdS/TiO 2 /Pt photocathode improved the PEC properties of CZTSSe thin films greatly and the highest water splitting photocurrents of 7.2 mA/cm−2 had been achieved under simulated solar illumination. Furthermore, the electrode showed good stability and had a good incident photon-to-current efficiency (IPCE) response in the visible light range. [ABSTRACT FROM AUTHOR]

Magnetic compounds with significant and temperature-insensitive magnetoresistance are quite promising for device applications. Here, we intentionally doped different amounts (0.025-0.1) of Co into epitaxial (La0.7Sr0.3)MnO3 thin films. The evolution of electrical, magnetic, magneto-transport, and valence state of this series of Co-doped (La0.7Sr0.3)MnO3 have been systematically characterized. Remarkably, the magnetoresistance in 0.1Co-doped (La0.7Sr0.3)MnO3 can reach significantly 35% within an extremely large temperature window (from 40 to 200 K). Other Co-doped epitaxial (La0.7Sr0.3)MnO3 thin films show similar sharp MR-peaks around Curie temperature as that in (La0.7Sr0.3)MnO3. The evolution of magnetic and magneto-transport properties of Co-(La0.7Sr0.3)MnO3 films can be explained by antiferromagnetic coupling induced by paramagnetic/low-spin Co3+(Co2+) ions in (La0.7Sr0.3)MnO3. Our work demonstrates that doping paramagnetic/low-spin Co into manganites is an effective way to optimize their magneto-transport properties. [ABSTRACT FROM AUTHOR]

Herein, we firstly present Er-doped MoS 2 films with a quasi-closed crucible method in chemical vapor deposition (CVD) system. ErCl 3 ·6H 2 O is exploited as the dopant and assistant agent. The Raman analysis indicates that doped samples are uniform and high crystalline quality which has two prominent peaks with the minimum FWHM ~4 cm −1 of E 2g 1 . However, Er dopant caused a red-shift in PL spectra. Furthermore, doped samples present a clear absorption edge at 1.8 eV and a small split peak of B exciton, which is attributed to the formation of impurity levels in Er-doped MoS 2 based on the DFT calculations. [ABSTRACT FROM AUTHOR]

By using pulsed laser deposition, Ba 0.95 La 0.05 PbO 3 (BLPO) thin films with different substrate temperatures (550–750 °C) and oxygen pressures (5–20 Pa) were prepared on SrTiO 3 (100) substrates. The charge valences of Ba and Pb cations in all the films are determined to be +2 and +4 by x-ray photoelectron spectroscopy. However, surface roughness of the films doesn’t keep unchanged, it increases with increasing temperature and oxygen pressure. The resistivity is significantly affected by substrate temperature and oxygen pressure, which increases with the former and decreases with the latter. Especially, the films deposited under 600 °C and 10 Pa oxygen pressure show metallic transport behavior with nearly temperature-insensitive values, as evidenced by the resistivity of 6.24×10 −5 Ω m and 5.41×10 −5 Ω m at 300 K and 15 K, respectively. Based on the structure and transport measurements, the optimized deposition conditions are determined to be close to 600 °C and 10 Pa. This work may provide some helpful clues for further work on tuning properties of BLPO films. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of monolithic perovskite/silicon tandem solar cells has surpassed that of silicon single-junction solar cells recently. Industrial textured crystalline silicon heterojunction solar cells are considered as competitive candidate bottom cells because of their high efficiency and simple process flow. Meanwhile, the front transparent conductive window layers with industrial compatibility and low processing temperature are worth investigating in detail. In this work, zinc-doped indium oxide (IZO) thin films achieved by room-temperature sputtering are studied as a function of sputtering powers. The IZO thin film with the resistivity and electron mobility of 7.2 × 10−4 Ω cm and 40.03 cm2/Vs are obtained under 85 W, which is implemented into the monolithic perovskite/silicon tandem solar cells. A PCE of 19.38% is realized based on the industrial textured silicon heterojunction bottom solar cell and optimized IZO films. • Industrial textured SHJ solar cells was used as the bottom cell of the PSSCs. • Optimal sputtering power of 85 W was obtained for the IZO films with the best FOM. • 60 nm IZO facilitates a higher short circuit current and a better current match between the sub-cells. • 1 cm2 two-terminal PSSC with PCE of 19.38% were demonstrated without additional anti-reflection layers. [ABSTRACT FROM AUTHOR]

[Display omitted] • In 2 S 3 thin films with petal-shaped microspheres were synthesized by chemical bath deposition. • Physical properties of In 2 S 3 thin films with petal-shaped microspheres were investigated. • PEC properties of In 2 S 3 thin films with petal-shaped microspheres were studied. In this paper, In 2 S 3 thin films were prepared by chemical bath deposition. The photoelectric properties of In 2 S 3 thin films were optimized by controlling the amount of acetic acid. The structural characteristics of In 2 S 3 were characterized by X-ray diffraction (XRD). The morphologies of In 2 S 3 thin films were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). The bandgaps of In 2 S 3 thin films were measured by UV–Vis-NIR spectra. PEC measurements indicated that when 0.4 M CH 3 CO 2 H was added, the PEC property of In 2 S 3 was the best, and highest photocurrent density was 41.93 μA/cm2. [ABSTRACT FROM AUTHOR]

• SnS nanosheets were chemical synthesized. • Ag nanoparticles modified the surface of SnS nanosheets. • photoelectic properties of SnS:Ag nanosheets were investigated. In this paper, tin monosulfide (SnS) nanosheets were prepared by one-pot method and silver (Ag) nanoparticles (NPs) were deposited on the SnS nanosheets (NSs) through a photochemical reduction process. X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and energy spectrometer (EDS), UV–Vis-NIR diffuse reflectance spectroscopy were used to characterize the physical properties of the SnS:Ag NSs. Photoelectrochemical tests indicated that Ag NPs enhanced the photoelectric properties of SnS NSs and the highest photocurrent density of 14.93 μA/cm2 was achieved. [ABSTRACT FROM AUTHOR]

In this paper, Cu doped CdS thin films were prepared on FTO substrates by RF magnetron sputtering and then were annealed at 350 °C–425 °C in vacuum for 20 min. The influences of different Cu-doped concentrations (Cu 4.1, 5.4, 7.3, 9.1 at%) on morphological, structural, optical properties and photo-electrochemical (PEC) properties of CdS thin films were investigated. The PEC characterizations indicated that the photocurrent densities of CdS:Cu (Cu 4.1, 5.4, 7.3, 9.1 at%) thin films increased from 0.94, 1.28,1.86,1.91 mA cm−2 to 1.33, 1.89, 2.40, 3.16 mA cm−2 after annealing. And the PEC properties of CdS:Cu thin films annealed at different temperatures were also studied. FTO/annealed CdS:Cu/Pt photoanode were fabricated to enhance the photocurrent activity and the photocurrent density of FTO/annealed CdS:Cu/5 nm Pt is 1.5 times larger than that of the CdS:Cu electrode without Pt cocatalyst. • CdS:Cu thin films were firstly prepared by magnetron sputtering method. • PEC properties of n type CdS:Cu thin films were firstly studied. • FTO/CdS:Cu/Pt improved PEC performances of CdS:Cu thin films. [ABSTRACT FROM AUTHOR]