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Eu2+-activated phosphors are widely applied in lighting and display areas because of their good optical performance. In this paper, an excellent green-emitting zeolite-3A: 1.3 wt% Eu phosphor is prepared by a green and eco-friendly high-thermal reaction method without any reducing atmosphere or agents. Meanwhile, the reducing mechanism from Eu3+ ions to Eu2+ ions is investigated. The experiment results show that the morphology, crystal structure, and luminescent property are affected by sintering temperature. The resulting sample shows the broad excitation band is in the range of 310–450 nm and the peak of the broad emission band is located at 523 nm. Furthermore, zeolite-3A: 1.3 wt% Eu phosphor is encapsulated on a commercial UV-emitting chip to fabricate a purity green light-emitting diode (LED) with the Commission Internationale de L’Eclairage (CIE) color coordinates at (0.295, 0.537).

Due to the advantages of narrow energy distribution of plasmonic hot-electrons in Ag and the high density of states in the TiO2 conduction band, an Ag/TiO2 composite is considered to be an ideal combination to construct a plasmonic hot-electron photodetector with high detectivity and a high response speed. In this work, we fabricate a porous Ag/TiO2-Schottky-diode based plasmonic hot-electron photodetector. This detector shows a high detectivity of 9.8 × 1010 cmHz1/2/W and a fast response speed, with a rise and fall time of 112 μs and 24 μs, respectively, under 450 nm light illumination at zero bias voltage. In addition, the height of the Ag/TiO2 Schottky barrier can be decreased by removing the chemisorbed oxygen from the surface of TiO2 with ultraviolet light illumination, and as a result, the responsivity of the Ag/TiO2 plasmonic hot-electron photodetector at 450 nm can increase from 3.4 mA/W to 7.4 mA/W.

This paper presents a systematic study of Raman spectra of nanocomposite photonic crystals produced using opal matrices or anodic aluminum oxide and filled with various inorganic compounds. We compare Raman spectra of the starting inorganic compounds (K2Cr2O7, CrO3, and KIO3) and nanocomposite photonic crystals whose pores are filled with the inorganic substances. Our results open up the possibility of producing high-performance sensors of inorganic substances introduced into the pores of photonic crystals, based on analysis of enhanced Raman scattering in a nanocomposite photonic crystal.

In this article, pure and tungsten-doped (W-doped) highly ordered two-dimensional (2D) vanadium dioxide (VO2) nanowire arrays were successfully prepared by a hydrothermal treatment, followed by a self-assembly progress and the in-situ high temperature treatment. The infrared photodetector devices based on monoclinic VO2 (VO2(M)) and W-doped VO2(M) nanowires were comparatively studied . It was found that the device based on W-doped VO2(M) nanowires exhibits a rapid infrared response and an enhanced photoelectric responsivity of 21.4 mA/W under the incident infrared light intensity of 280 mW/cm2, which is nearly two orders of magnitude superior to pure VO2(M) nanowire array. Our experimental results provided a direct and convenient path for design of future high-performance photodetector devices.

Herein, we report an enhanced tunable broadband wavelength-selective lead sulfide (PbS) film detector integrated with Au-nanorod arrays that were obtained by using an ultrathin open-ended porous titanium dioxide membrane (UOP-TM) as a mask. The responsivity of the PbS films with periodic Au-nanorods exhibits a drastic enhancement by up to 125%–175% due to the enhancement of the localized electromagnetic fields around the gold nanorods. Notably, the location of the strongest enhancement peak of photocurrent shifted from 450 to 980 nm as the height of the Au-nanorods increased from 30 to 120 nm. In addition, the responsivity and detectivity of the hybrid PbS film modified with 90 nm Au-nanorod arrays under laser illumination of 980 nm are as high as 944 mA W−1 and 1.72 × 1010 cm Hz1/2 W−1, respectively. These excellent figures-of-merit of the tunable broadband plasma-enhanced PbS films could be a promising candidate in future wavelength-selective photodetector applications.

High-quality Sn2+-sensitized PbS films were deposited via a cost‐effective chemical route. The results demonstrate that the Sn2+-sensitized PbS thin films have better crystallinity and larger grain size. Photoelectric performance of Sn2+-sensitized PbS films has been improved greatly in the visible and near-infrared range. With Sn2+ sensibilization, photoresponsivity is more than 9 times higher, and detectivity is as high as ~1010 cm2 Hz1/2 W−1. Notably, the response speed of the Sn2+-sensitized PbS films reaches a magnitude of microseconds, which is over 105 times improvements compared with the pure PbS film devices. Additionally, high-frequency switching behavior at 4 kHz shows excellent stability. Based on the feasible method and excellent photoelectric performance of the devices, it has been demonstrated that Sn2+ sensibilization is of viability to improve the detection performance of commercial photodetectors.

A high strain sensor composed of elastomer polydimethylsiloxane (PDMS) and polyaniline (PANI) was fabricated by electrodeposition method for PANI preparation and daubing method for PDMS preparation. This kind of sensor could subject to a large tensile strain (∼50%) and revealed a high gauge factor (54 at 50% strain), which was higher than other sensors reported previously. Also, the sensor displayed a current with a magnitude of mA when applied to 1 V, indicating it didn't need expensive and huge test equipment. Moreover, cyclic strain on the sensor obtained repeatable resistive responses. Its work mechanisms were discussed. The flexible sensor was proved to be useful in sensing strains and other various applications.

A type of metal-semiconductor-metal (MSM) photodetector based on PbTe single-crystalline nanowires was prepared. I–V characteristics of the photodetector in the temperature range of 77–300 K were studied. Little dark current was achieved in MSM PbTe nanowire photodetector at low bias voltages due to the formation of back to back Schottky junctions between the PbTe nanowires and Au electrodes. The influences of light intensity, bias voltage, and temperature on the performance of PbTe nanowire photodetector were investigated. It was found that the photocurrent is linear to light intensity. The photosensitivity of the typical photodetector was about 50% and varied only slightly as a function of bias voltage. Moreover, this photodetector displayed a fast respond compared with nanoparticle photodetector due to the one dimensional structure and the high crystallinity of nanowires.

In this paper, we fabricate ordered pore array (OPA) Ag film coated glass with the aid of polystyrene sphere (PS) array templates. This kind of OPA Ag coated glass has optical advantages of visible transparency, blue and near-infrared resistance. The average visible transmittance is 68%, including a transmission peak of 78% located at 570 nm, and low average transmittance of 48% in the blue light region that is not damaging to the eyes. The near-infrared light blocking rate is 67%, among which 40% light is reflected directly, indicating the reflection domination.

Uniform tellurium nanowires (NWs), nanotubes (NTs) and trifold nanorods (NRs) were synthesized using a facile, environmentally benign solvothermal method with ethylene glycol as solvent, polyvinylpyrrolidone as surfactant and non-hazardous ascorbic acid as a reducing agent. By adjusting the amounts of the surfactant and the reducing agent, Te NWs, NTs and trifold NRs were prepared. The diameter of the Te NWs and NTs are 30–40 nm and 120–150 nm, respectively. A morphology evolution diagram based on different amounts of polyvinylpyrrolidone and ascorbic acid aqueous solution are presented. The effects of temperature are also investigated meticulously. The growth mechanism of the Te NTs and trifold Te NRs are discussed based on the crystallization law. The photoelectrical properties of the Te NWs and trifold Te NRs were measured. The photocurrent and responsivity of the photodetector based on Te NWs are 0.17 mA and 25.8 A W−1, respectively.

Although phototransistors for controlling photocurrent with electricity have been studied intensively for several decades, transistors with all-optical inputs that can control the photocurrent with light have not been investigated thus far. In this paper, a plasmonic porous Ag/TiO transistor is fabricated with all-optical inputs. One light input acts as the source to generate a plasmonic-hot-electron photocurrent, while the other gate light changes the current channel by adjusting the height of an Ag/TiO Schottky barrier. As a result, the plasmon-induced photocurrent generated by the source light can be enhanced by several to one hundred times by controlling the gate light. In addition to signal enhancement, the device can also be used for signal modulation and switching., This work was supported by the National Basic Research Program of China (973 Program) (Grant No. 2012CB932303), the National Natural Science Foundation of China (Grant Nos. 51701207, 51471162, 51502294, and 51671183), the CAS/SAFEA International Partnership Program for Creative Research Teams, and the Foundation of Director of Institute of Solid State Physics, Chinese Academy of Sciences (Grant No. 2016DFY20).

Composite hollow nanostructure composed by transition metal oxides are promising materials in electrochemistry, catalyst chemistry and material science. In this contribution, necklace-like NiO-CuO heterogeneous composite hollow nanostructures were synthesized by annealing Ni/Cu superlattice nanowires in air. Two kinds of morphologies including CuO nanotube linked core-shell structures and CuO nanotube linked hollow structures were obtained. The structure can be tuned easily by adjusting the relative length of Cu segments in Ni/Cu superlattice nanowires and the annealing temperature. The relative diffusion amount of Cu to Ni segments was proved to be the key factor to influence the annealed sample morphology. The formation mechanism was discussed in detail based on Kirkendal effect and high temperature oxidation of alloy. We demonstrated that hollow structure or core-shell structure is related to whether the oxidation exists only in external sites or co-exists in external and internal sites during annealing.

One-dimensional noble-metal Ag nanoparticle chains have been prepared by electrodepositing Ag/Bi superlattice nanowires in a porous anodic alumina oxide (AAO) template and following an annealing process in vacuum. It is found that Bi, as a sacrificial metal, can be removed completely after annealing at 450 °C with a vacuum degree of 10(-5) Torr. The regulation of particle size, shape and interparticle spacing of Ag NP chains has been realized by adjusting the segment length of the Ag/Bi superlattice nanowires and the annealing condition. With an extension of the annealing time, it is observed that Ag particles display the transform trend from ellipsoid to sphere. Our findings could inspire further investigation on the design and fabrication of metal nanoparticle chains.