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Organic‐inorganic hybrid perovskite solar cells (PSCs) have developed rapidly in recent years owing to the low cost and high power conversion efficiency achieved. The excellent performance of PSCs is attributed to the superior electrical properties of each layer, including the electron transport layer (ETL), light‐harvest layer, hole transport layer. As one of the most promising ETL materials for PSCs, SnO2 shows excellent transmission, an appropriate energy band gap, a deep conduction band level, and high electron mobility, leading to efficient electron extraction and transport. Here, recent advancements in the PSCs with SnO2 ETLs and endeavors aimed at improving the performance of this photovoltaic device are reviewed. Several typical configurations of SnO2 based PSCs are discussed, including the planar structure, mesoporous structure, inverted structure and flexible PSCs. The efforts of modification and composite SnO2 with other metal oxides are also assessed. Finally, an overview of the perspectives and challenges for the future of SnO2 based PSCs is provided.

In this paper, we give a review of our theoretical and experimental progress in octahedral spherical hohlraum study. From our theoretical study, the octahedral spherical hohlraums with 6 Laser Entrance Holes (LEHs) of octahedral symmetry have robust high symmetry during the capsule implosion at hohlraum-to-capsule radius ratio larger than 3.7. In addition, the octahedral spherical hohlraums also have potential superiority on low backscattering without supplementary technology. We studied the laser arrangement and constraints of the octahedral spherical hohlraums, and gave a design on the laser arrangement for ignition octahedral hohlraums. As a result, the injection angle of laser beams of 50°–60° was proposed as the optimum candidate range for the octahedral spherical hohlraums. We proposed a novel octahedral spherical hohlraum with cylindrical LEHs and LEH shields, in order to increase the laser coupling efficiency and improve the capsule symmetry and to mitigate the influence of the wall blowoff on laser transport. We studied on the sensitivity of the octahedral spherical hohlraums to random errors and compared the sensitivity among the octahedral spherical hohlraums, the rugby hohlraums and the cylindrical hohlraums, and the results show that the octahedral spherical hohlraums are robust to these random errors while the cylindrical hohlraums are the most sensitive. Up till to now, we have carried out three experiments on the spherical hohlraum with 2 LEHs on Shenguang(SG) laser facilities, including demonstration of improving laser transport by using the cylindrical LEHs in the spherical hohlraums, spherical hohlraum energetics on the SGIII prototype laser facility, and comparisons of laser plasma instabilities between the spherical hohlraums and the cylindrical hohlraums on the SGIII laser facility.

Abstract:We have developed a method to equip homodyne interferometers with the capability to operate with constant high sensitivity over many fringes for continuous real-time tracking. The method can be considered as an extension of the "J 1 ...J 4 " methods, and its enhancement to deliver very sensitive angular measurements through Differential Wavefront Sensing is straightforward. Beam generation requires a sinusoidal phase modulation of several radians in one interferometer arm. On a stable optical bench, we have demonstrated a long-term sensitivity over thousands of seconds of 0.1 mrad/ √ Hz that correspond to 20 pm/ √ Hz in length, and 10 nrad/ √ Hz in angle at millihertz frequencies.

L37 ConclusionsA highly successful procedure has been developed which allows deposition of thin-film ceramics on highly porous substrates. The methodology is inexpensive and scalable. Thin-film SOFCs fabricated using these techniques demonstrate performances of close to 2 W/cm2 at 800°C. Current interrupt techniques indicate the majority of the voltage loss at high current density is due to ohmic losses, most likely associated with cathode/electrolyte contact resistance (0.1 i cm2). The exceptional performance of the thinfilm SOFC5 implies that reduced temperature operation is possible while still maintaining high power density. ABSTRACTHighly selective chemical etching of Si vs. epitaxial Si1 Ge in NH4OH solution has been investigated. It was found the selectivity was better than 80:1 even for a Si09Ge0, in 10 weight percent(w/o) NH4OH at 75°C. As the fraction xof Ge was increased, higher selectivity was obtained due to the decrease of the etch rate of the Si -The achievement of the excellent selectivity in a Si/Si Ge/Si heterostructure was clearly demonstrated by scanning electron microscopy. Surfaces of etched Si1, ,Ge, samples were analyzed using x-ray photoelectron spectroscopy. The high etch selectivity obtained in NH4OH is essentially due to a passivation-film effect at the Si1Ge surface.