A facile hydrothermal synthesis route to N and S, co-doped graphene quantum dots (GQDs) was developed by using citric acid as the C source urea or thiourea S sources. Both doped GQDs showed high yield (78% 71%), excitation independent under of 340–400 nm single exponential decay UV excitation. broad absorption band in visible region appeared due doping with sulfur, which alters surface state GQDs. However, show different color emission 420–520 their region. The excellent photocatalytic...

Photoluminescent graphene quantum dots (GQDs) have received enormous attention because of their unique chemical, electronic and optical properties. Here a series GQDs were synthesized under hydrothermal processes in order to investigate the formation process properties N-doped GQDs. Citric acid (CA) was used as carbon precursor self-assembled into sheet structure basic condition formed N-free GQD graphite framework through intermolecular dehydrolysis reaction. prepared using N-containing...

Iron is one of the most important elements in metabolic process for all living system. However, both its deficiency and excess from normal permissible limits can induce serious disorders. We synthesized a europium-based metal-organic framework (Eu-MOF), EuL(3) (L = 4'-(4-carboxyphenyl)-2,2': 6',2″-terpyridine), under hydrothermal conditions, used it as solid luminescence sensor Fe(3+) ions. The robust shows fast response (∼ 1 min) high sensitivity (Stern-Volmer constant K(SV) 4.1 × 10(3)...

Abstract Super broadband near‐infrared (NIR) phosphor converted light‐emitting diodes (pc‐LEDs) are future light sources in NIR spectroscopy applications such as food testing. At present, a few blue LED excitable super phosphors (bandwidth > 300 nm) have been developed producing the output powers below 26 mW at 100 mA input current after packaging. Here, an efficient achieved by doping Yb 3+ is reported Ca 2 LuZr Al 3 O 12 :Cr (CLZA:Cr ) garnet previously. Benefited from superposition of...

In this work, the optical properties of carbon nanoparticles (CNPs) can be modulated by dopant‐N atom and sp 2 C‐contents. CNPs prepared with low urea mass ratio 0.2:1 (CNP1) exhibit blue emission (maximum PL quantum yield: 15%). Increasing C‐ contents, as determined in high 2:1 (CNP2), lead to green yield up 36% ethanol aqueous solution). Amplified spontaneous (ASE) observed only CNP2 solution. Green lasing is achieved from solution a linear long Fabry‐Perot cavity, indicating potential...

A new type of environmentally friendly phosphor based on carbon nanodots (CDs) has been developed through the dispersion CDs by integrating with starch particles. The particles contain large numbers hydroxyl groups around surfaces, which can effectively absorb CDs, whose surfaces are functionalized lots carboxyl and amide groups, hydrogen bonding. Effective suppress non-radiative decay processes photoluminescence (PL) quenching induced aggregation CDs. matrix neither competes for absorbing...

A new method for the growth of high-quality ZnO nanoparticles is presented here; it a novel, low-cost, and easy operation. This approach, using solid-state heat decomposition at low temperature, allows one to produce with relatively high dispersivity. The optical properties have been investigated. It demonstrated that show strong ultraviolet emission, while low-energy visible emission nearly fully quenched room temperature. result quality ZnO. X-ray diffraction patterns reveal...

Novel blue-emitting K2Al2B2O7:Eu2+ (KAB:Eu2+) phosphor was synthesized by solid state reaction. The crystal structural and photoluminescence (PL) properties of KAB:Eu2+ phosphor, as well its thermal the photoluminescence, were investigated. exhibits broad excitation spectra ranging from 230 to 420 nm, an intense asymmetric blue emission band centered at 450 nm under λex = 325 nm. Two different Eu2+ centers in confirmed via their fluorescence decay lifetimes. optimal concentration ions...

Red upconversion luminescence (UCL) is selectively enhanced <italic>via</italic> Fe³⁺ codoping into a NaYF₄:Yb,Er nanocrystalline lattice showing remarkable promise as multimodal nanoprobe for biomedical imaging.

A visual colorimetric dipicolinic acid sensor was prepared by modulating the energy transfer process in MOF.

Bright red upconversion phosphor Ba₃Y₄O₉:Er³⁺/Yb³⁺ and dual-color complementary optical thermometry to maintain relatively high sensitivities over a wide temperature scope.

An ultra-high sensitive acetylene (C2H2) Quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor based on a high power laser and quartz tuning fork with resonance frequency f0 of 30.72 kHz was demonstrated. erbium-doped fiber amplifier (EDFA) amplified distributed feedback diode center wavelength 1.53 μm used as the exciting source. A 33.2 ppb minimum detection limit (MDL) at 6534.37 cm−1 achieved, calculated normalized noise equivalent absorption coefficient 3.54 × 10−8 W/√Hz when output...

Inorganic semiconductor-based photodetectors have been suffering from slow response speeds, which are caused by the persistent photoconductivity of semiconductor materials. For realizing high speed optoelectronic devices, organometal halide perovskite thin films were applied onto interdigitated (IDT) patterned Au electrodes, and symmetrical structured photoconductive detectors achieved. The sensitive to incident light signals, photocurrents devices 2–3 orders magnitude higher than dark...

Defects (Ti3+ or oxygen vacancies) have been demonstrated to promote the charge separation process in TiO2 based photocatalysts. Particularly, bulk defects within a certain concentration can give great enhancement for both light absorption and efficiency. In this report, we explored one-step molten salts route synthesize SrTiO3 nanocubes with doped) by using SrCO3 as Sr source, Ti powder sources. The amount of be tuned changing molar ratio Ti/TiO2. corresponding bandgap changed from 3.29...

The piezoresistive behavior of a silicon carbonitride ceramic derived from polymer precursor is investigated under uniaxial compressive loading condition. electric conductivity has been measured as function the applied stress along both longitudinal and transverse directions. gauge factor materials was then calculated data at different levels. results show that material exhibits an extremely high coefficient directions, ranging 1000 to 4000, which are much higher than any existing material....

We report on bandgap engineering of an emerging photovoltaic material Cu2CdxZn1−xSnS4 (CCZTS) alloy. CCZTS alloy thin films with different Cd contents and single kesterite phase were fabricated using the sol-gel method. The optical absorption measurements indicate that can be continuously tuned in a range 1.55–1.09 eV as content varied from x = 0 to 1. Hall effect suggest hole concentration decreases increasing content. CCZTS-based solar cell 0.47 demonstrates power conversion efficiency...

Through introducing a probe layer of bis(4,6-difluorophenylpyridinato-N,C2)picolinatoiridium (FIrpic) between QD emission and 4, 4-N, N- dicarbazole-biphenyl (CBP) hole transport layer, we successfully demonstrate that the electroluminescence (EL) mechanism inverted quantum dot light-emitting diodes (QD-LEDs) with ZnO nanoparticle electron injection/transport should be direct charge-injection from charge layers into QDs. Further, EL QD-LEDs at sub-bandgap drive voltages is achieved, which in...

Dexmedetomidine is an α2-adrenergic receptor agonist that exhibits a protective effect on ischemia-reperfusion injury of the heart, kidney, and other organs. In present study, we examined neuroprotective action potential mechanisms dexmedetomidine against induced cerebral injury. Transient focal was in Sprague-Dawley rats by middle artery occlusion. After ischemic insult, animals then received intravenous 1 µg/kg load dose, followed 0.05 µg/kg/min infusion for 2 h. 24 h reperfusion,...