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The exploration on efficient self-powered solar-blind photodetectors is essential for future sustainable optoelectronic system under tremendous application scenarios. Herein, we demonstrate a photoelectrochemical (PEC)-type heterojunction-driven solar-blind detector constructed by atomic...

Iodine molecules confined in the elliptical nanochannels of AlPO4-11 crystals can only rotate in the plane passing through the major axis of the elliptical cross-section due to size confinement. This leads to different dynamic behaviors of iodine from those confined in round channels of AlPO4-5 crystals under ambient conditions. In this work, we use high pressure technology to manipulate the nanoscaled iodine species confined in the elliptical channels of AlPO4-11 crystals. In situ polarized Raman measurements and theoretical simulations have been carried out to study the topological geometry of the confined iodine species upon compression. It was found that the population of iodine chains could significantly increase at the expense of standing iodine molecules under pressure up to 6 GPa, due to the pressure-induced rotation of standing iodine molecules. Besides, the contraction of the host framework along the channel axis favors the formation of iodine chains and strengthens the interaction of neighbouring molecules in a chain, consequently leading to a frequency redshift of the corresponding Raman mode. The different transformation dynamics of the confined iodine in AlPO4-11 crystals upon compression, compared to those in round channels of AlPO4-5 crystals, have been discussed in terms of the unique nanochannels that offer the quasi two-dimensional nanoscaled confinement environment.

Soft-X-ray interference lithography is utilized in combination with atomic layer deposition to prepare photonic crystal structures on the surface of Bi4Ge3O12 (BGO) scintillator in order to extract the light otherwise trapped in the internal of scintillator due to total internal reflection. An enhancement with wavelength- and emergence angle-integration by 95.1% has been achieved. This method is advantageous to fabricate photonic crystal structures with large-area and high-index-contrast which enable a high-efficient coupling of evanescent field and the photonic crystal structures. Generally, the method demonstrated in this work is also suitable for many other light emitting devices where a large-area is required in the practical applications.