An Ultra-broadband Metallic Plasmonic Antenna for Ultrasensitive Molecular Fingerprint Identification.

Near-field enhanced mid-infrared light-matter interactions via metallic plasmonic antennae (PA) have attracted much attention but are inevitably limited by the detuning between their narrow band and the broad applied spectral range. Here, we develop a new low-temperature incubation synthetic method to acquire uniform Ag microparticles (MPs) with numerous hotspots. Their plasmonic band is remarkably extended by the plasmonic coupling of numerous hotspots and covers the entire mid-infrared range (400-4000 cm-1). Hence, the almost complete molecular fingerprint of 4-mercaptobenzonitrile was successfully probed for the first time via resonant surface-enhanced infrared absorption (rSEIRA), and the rSEIRA spectra of different essential amino acids were further detected and exhibit a high spectral identification degree assisted by machine learning. This work changes the inertia perception of "narrow band and large size but small hotspot area" of mid-infrared metallic PA and paves the way for the ultrasensitive mid-infrared optical sensing.

Bridging the gap between surface physics and photonics.

Use and performance criteria of photonic devices increase in various application areas such as information and communication, lighting, and photovoltaics. In many current and future photonic devices, surfaces of a semiconductor crystal are a weak part causing significant photo-electric losses and malfunctions in applications. These surface challenges, many of which arise from material defects at semiconductor surfaces, include signal attenuation in waveguides, light absorption in light emitting diodes, non-radiative recombination of carriers in solar cells, leakage (dark) current of photodiodes, and light reflection at solar cell interfaces for instance. To reduce harmful surface effects, the optical and electrical passivation of devices has been developed for several decades, especially with the methods of semiconductor technology. Because atomic scale control and knowledge of surface-related phenomena have become relevant to increase the performance of different devices, it might be useful to enhance the bridging of surface physics to photonics. Toward that target, we review some evolving research subjects with open questions and possible solutions, which hopefully provide example connecting points between photonic device passivation and surface physics. One question is related to the properties of the wet chemically cleaned semiconductor surfaces which are typically utilized in device manufacturing processes, but which appear to be different from crystalline surfaces studied in ultrahigh vacuum by physicists. In devices, a defective semiconductor surface often lies at an embedded interface formed by a thin metal or insulator film grown on the semiconductor crystal, which makes the measurements of its atomic and electronic structures difficult. To understand these interface properties, it is essential to combine quantum mechanical simulation methods. This review also covers metal-semiconductor interfaces which are included in most photonic devices to transmit electric carriers to the semiconductor structure. Low-resistive and passivated contacts with an ultrathin tunneling barrier are an emergent solution to control electrical losses in photonic devices.

Hydrothermally Stimulated Molecular Interfaces for Augmented Electron Delocalization in Wet-Chemical Phosphorus Recovery from Incineration Ash of Sewage Sludge.

Wet-chemically recovering phosphorus (P) from sewage sludge incineration ash (SSIA) has already become a global initiative to address P deficit, but effectively isolating P from these accompanying metals (AMs) through adsorption in a SSIA-derived extract remains elusive. Here, we devised a hydrothermal stimulus-motivated thermodynamic and kinetic enhancement to gain anionic ethylenediaminetetraacetic acid (EDTA) molecular interfaces for AM enclosure to resolve this conundrum. A new dosage rule based on the EDTA coordination ratio with AMs was established for the first time. Upon hydrothermal extraction at 140 °C for 1 h, the P extraction efficiency reached 96.7% or higher for these obtained SSIA samples, and then exceptional P sequestration from these EDTA-chelated AMs was realized by the peculiar lanthanum (La)-based nanoadsorbent (having 188.86 mg P/g adsorbent at pH ∼ 3.0). Relevant theoretical calculations unraveled that these delocalized electrons of tetravalent EDTA molecules boosted the enclosure of liberated AMs, thereby entailing a substantially increased negative adsorption energy (-408.7 kcal/mol) of P in the form of H2PO4- through intruding lattice-edged carbonates to coordinate La with monodentate mononuclear over LaCO5(1 0 1). This work highlights the prospect of molecular adaptation of these common extractants in wet-chemical P recovery from various P-included wastes, further sustaining global P circularity.

Realization of smooth side profile using diffusion-controlled wet chemical etching for HgTe/(Hg,Cd)Te heterostructures.

We utilize a diffusion-controlled wet chemical etching technique to fabricate microstructures from two-dimensional HgTe/(Hg,Cd)Te-based topological insulators. For this purpose, we employ a KI: I2: HBr: H2O-based etchant. Investigation of the side profile of the etched heterostructure reveals that HgTe quantum wells protrude from the layer stack as a result of the different etch rates of the layers. This constraint poses challenges for the study of the transport properties of edge channels in HgTe quantum wells. In order to achieve a smoother side profile, we develop a novel approach to the etching process involving the incorporation of a sacrificial design element in the etch mask. This limits the flow of charge carriers to the ions in the electrolyte during the etching process. The simplicity of the method coupled with the promising results achieved thereby should make it possible for the new approach introduced here to be applied to other semiconductor heterostructures.

Influence of Annealing on the Structural, Morphological, Photoluminescence and Visible Absorption Properties of Mg Doped CuO Micro Grains.

Narrow band gap oxide materials that harvest visible light have gained considerable attention for numerous visible light mediated applications. In this current work, a typical Mg doped CuO bulk material was prepared by a simple wet chemical method. The prepared material was annealed in three different temperatures viz.; 300 °C, 400 and 500 °C in air atmosphere to tune the optical band gap. XRD studies reveal that the average crystallite size increases with increase in annealing temperature. FESEM images of all the samples show their bulk nature with different grain sizes and morphologies. XPS survey scan spectra exhibit photoelectron emissions of Cu2p, O1s and Mg 1s with binding energies 933.69 eV, 533.41 eV and 1304.2 eV for all the samples and validated the effective incorporation of Mg ions into the CuO lattice. PL spectra reveal the polychromatic UV- visible luminescence bands for all the annealed samples, whereby the PL intensity is found to be decreasing as the annealing temperature increases. Finally, the band gap decreases with annealing temperature and indicates that the sample annealed at 500 °C can be exploited for visible light assisted applications such as solar cells, photocatalysis and photoelectrochemical cell.

One-pot wet-chemical fabrication of 3D urchin-like core-shell Au@PdCu nanocrystals for electrochemical breast cancer immunoassay.

Carbohydrate antigen 15-3 (CA15-3) is an important biomarker for early diagnosis of breast cancer. Herein, a label-free electrochemical immunosensor was built based on three-dimensional (3D) urchin-like core-shell Au@PdCu nanocrystals (labeled Au@PdCu NCs) for highly sensitive detection of CA15-3, where K3[Fe(CN)6] behaved as an electroactive probe. The Au@PdCu NCs were synthesized by a simple one-pot wet-chemical approach and the morphology, structures, and electrocatalytic property were investigated by several techniques. The Au@PdCu NCs prepared worked as electrode material to anchor more antibodies and as signal magnification material by virtue of its exceptional catalytic property. The developed biosensor exhibited a wide linear detection range from 0.1 to 300 U mL-1 and a low limit of detection (0.011 U mL-1, S/N = 3) for determination of CA15-3 under the optimal conditions. The established biosensing platform exhibits some insights for detecting other tumor biomarkers in clinical assays and early diagnosis.

Wet chemical synthesis of BiPO4 :Eu3+ phosphor for w-LED application.

The synthesis of BiPO4 :Eu3+ phosphors has been achieved via a wet chemical process. X-ray diffraction patterns show that the phase of the as-prepared samples matches very well with the standard BiPO4 structure. At 395 nm, the highest excitation intensity was observed. Following 395 nm excitation, two characteristic emission peaks at 592 nm and 616 nm were shown. At 0.5 mol% of Eu3+ ions, concentration quenching occurred. The particle size is within the micrometre range, according to the scanning electron microscope magnification. The chromaticity coordinates for wavelengths 592 nm and 616 nm are (x = 0.586, y = 0.412) and (x = 0.682, y = 0.317), respectively. The findings imply that the prepared phosphor may be used to create white light-emitting diodes.

Wet-Chemical Synthesis of TiO2/PVDF Membrane for Energy Applications.

To satisfy the ever-increasing energy demands, it is of the utmost importance to develop electrochemical materials capable of producing and storing energy in a highly efficient manner. Titanium dioxide (TiO2) has recently emerged as a promising choice in this field due to its non-toxicity, low cost, and eco-friendliness, in addition to its porosity, large surface area, good mechanical strength, and remarkable transport properties. Here, we present titanium dioxide nanoplates/polyvinylidene fluoride (TiO2/PVDF) membranes prepared by a straightforward hydrothermal strategy and vacuum filtration process. The as-synthesized TiO2/PVDF membrane was applied for energy storage applications. The fabricated TiO2/PVDF membrane served as the negative electrode for supercapacitors (SCs). The electrochemical properties of a TiO2/PVDF membrane were explored in an aqueous 6 M KOH electrolyte that exhibited good energy storage performance. Precisely, the TiO2/PVDF membrane delivered a high specific capacitance of 283.74 F/g at 1 A/g and maintained capacitance retention of 91% after 8000 cycles. Thanks to the synergistic effect of TiO2 and PVDF, the TiO2/PVDF membrane provided superior electrochemical performance as an electrode for a supercapacitor. These superior properties will likely be used in next-generation energy storage technologies.

Enhanced magnetic performance in exchange-coupled CoFe2O4-LaFeO3nanocomposites.

Nanocomposite oxide system of (x)CoFe2O4-(100-x)LaFeO3with different weight percent of core-shell structured CoFe2O4(x = 0, 20, 40, 50, 80, 100) and LaFeO3were fabricated, via a two-step sol-gel wet-chemical synthesis technique. The phase formation of the composites was confirmed by x-ray diffraction and the structural parameters of both the phases were attained from the Rietveld refinement results of XRD patterns. The elemental composition and microstructure of the resulting nanocomposites were examined by using energy-dispersive x-ray spectroscopy and high-resolution transmission electron microscopy technique, respectively. The detailed magnetometry studies at 300 K and 5 K reveal that the inter-and intra-phase magnetic interactions affect the saturation magnetization (MS), remanence magnetization (MR) and coercivity (HC) values of this bi-magnetic system. The remarkable feature of 'pinched magnetic hysteresis loop' was evidenced in the [(50) CoFe2O4- (50)LaFeO3] composite, leading to a lesser magnetic loss factor and better magnetic performance of this sample. The report depicts an improved interfacial exchange coupling at 5 K, for the nanocomposites of core-shell morphology and offers an understanding or explanation of improved magnetic performance for the (50)CoFe2O4- (50)LaFeO3nanocomposite and opens up an important way to design new multiferroic applications in low magnetic fields.

Wet-Chemically Prepared Porphyrin Layers on Rutile TiO2(110).

Porphyrins are large organic molecules that are interesting for different applications, such as photovoltaic cells, gas sensors, or in catalysis. For many of these applications, the interactions between adsorbed molecules and surfaces play a crucial role. Studies of porphyrins on surfaces typically fall into one of two groups: (1) evaporation onto well-defined single-crystal surfaces under well-controlled ultrahigh vacuum conditions or (2) more application-oriented wet chemical deposition onto less well-defined high surface area surfaces under ambient conditions. In this study, we will investigate the wet chemical deposition of 5-(monocarboxyphenyl)-10,15,20-triphenylporphyrin (MCTPP) on well-defined rutile TiO2(110) single crystals under ambient conditions. Prior to deposition, the TiO2(110) crystals were also cleaned wet-chemically under ambient conditions, meaning none of the preparation steps were done in ultrahigh vacuum. However, after each preparation step, the surfaces were characterized in ultrahigh vacuum with X-ray photoelectron spectroscopy (XPS) and the result was compared with porphyrin layers prepared in ultrahigh vacuum (UHV) by evaporation. The differences of both preparations when exposed to zinc ion solutions will also be discussed.

Bromide Ions Triggered Synthesis of Noble Metal-Based Intermetallic Nanocrystals.

Ordered intermetallic nanomaterials with a well-defined crystal structure and fixed stoichiometry facilitate the predictable control of their electronic structure and catalytic performance. To obtain the thermodynamically stable intermetallic structures, the conventional approaches with high-temperature annealing are still far from satisfactory, because of annealing-induced aggregation and sintering of nanomaterials. Herein, a general wet-chemical method is developed to synthesize a series of noble metal-based intermetallic nanocrystals, including hexagonal close-packed (hcp) PtBi nanoplates, face-centered cubic (fcc) Pd3 Pb nanocubes, and hcp Pd2.5 Bi1.5 nanoparticles. During the synthetic process, Br- ions play two important roles for the formation of ordered intermetallic structures: i) Br- ions can coordinate with the metal ions to decrease their reduction potentials thus slowing down the reduction kinetics. ii) Br- ions can combine with molecular oxygen to generate an oxidative etching effect, hence reconstructing the atom arrangement, which is beneficial for the formation of the intermetallic structure. As a proof-of-concept application, Pd3 Pb nanocubes are used as electrocatalysts for ethanol and methanol oxidation reactions, which exhibit significantly improved electrochemical performance compared with the commercial Pd black catalyst.

Controlling the Facet of ZnO during Wet Chemical Etching Its (000 1 ¯ ) O-Terminated Surface.

Special surface plays a crucial role in nature as well as in industry. Here, the surface morphology evolution of ZnO during wet etching is studied by in situ liquid cell transmission electron microscopy and ex situ wet chemical etching. Many hillocks are observed on the (000 1 ¯ ) O-terminated surface of ZnO nano/micro belts during in situ etching. Nanoparticles on the apex of the hillocks are observed to be essential for the formation of the hillocks, providing direct experimental evidence of the micromasking mechanism. The surfaces of the hillocks are identified to be {01 1 ¯ 3 ¯ } crystal facets, which is different from the known fact that {01 1 ¯ 1 ¯ } crystal facets appear on the (000 1 ¯ ) O-terminated surface of ZnO after wet chemical etching. O2 plasma treatment is found to be the key factor for the appearance of {01 1 ¯ 3 ¯ } instead of {01 1 ¯ 1 ¯ } crystal facets after etching for both ZnO nano/micro belts and bulk materials. The synergistic effect of acidic etching and O-rich surface caused by O2 plasma treatment is proposed to be the cause of the appearance of {01 1 ¯ 3 ¯ } crystal facets. This method can be extended to control the surface morphology of other materials during wet chemical etching.

Synthesis and photoluminescence properties of Eu3+ -activated Ba2 Mg(PO4 )2 phosphor.

In this paper, we have reported the photoluminescence (PL) properties of the Ba2 Mg(PO4 )2 :Eu3+ phosphor synthesized using a wet chemical method. The preliminary scanning electron microscopy (SEM) investigation of the sample revealed irregular surface morphology with particle sizes in the 10-50 µm range. The strongest PL excitation peak was observed at 396 nm. The emission spectra indicated that this phosphor can be effectively excited by the 396 nm wavelength. Upon 396 nm excitation, the emission spectrum showed characteristics peaks located at 592 nm and 615 nm. These intense orange-red emission peaks were obtained due to f→f transitions of Eu3+ ions. The emission peak at 592 nm is referred to as the magnetic dipole 5 D0 →7 F1 transition and the emission peak at 615 nm corresponded to the electric dipole 5 D0 →7 F2 transition of Eu3+ . The Commission Internationale de l'Eclairage (CIE) coordinates of the Ba2 Mg(PO4 )2 :Eu3+ phosphor were found to be (0.586, 0.412) for wavelength 592 nm and (0.680, 0.319) for wavelength 615 nm situated at the edge of the CIE diagram, indicating high colour purity of phosphors. Due to the high emission intensity and a good excitation profile, Eu3+ -doped Ba2 Mg(PO4 )2 phosphor may be a promising orange-red phosphor candidate for solid-state lighting applications.

Luminescence characterization of KBaPO4 :RE (RE = Sm3+ ,Eu3+ ,Dy3+ ) phosphors.

KBaPO4 luminescent powdered phosphors doped with rare earth elements (RE = Sm3+ ,Eu3+ ,Dy3+ ) were successfully synthesized using a wet chemical method to identify the most suitable phosphor for solid-state lighting based on the measurement of their emission spectra at excitation wavelengths. The X-ray diffraction pattern of the as-prepared KBaPO4 was well matched with its standard JCPDS file no. 330996, indicating the formation of the desired compound. Scanning electron microscopy images revealed irregular morphology, the material crystallized particles aggregated and were non-uniform with particle sizes ranging from 1 to 100 µm. Photoluminescence excitation and emission spectra clearly indicated that the phosphor containing the Sm3+ -activated KBaPO4 phosphors could be efficiently excited at 403 nm and exhibited an emission mainly including two wavelength peaks at 559 nm and 597 nm. The phosphor containing the Eu3+ -activated KBaPO4 phosphors could be efficiently excited at 396 nm and exhibited a bright red emission mainly including two wavelength peaks at 594 nm and 617 nm. The phosphor containing the Dy3+ -activated KBaPO4 phosphors could be efficiently excited at 349 nm and exhibited wavelength peaks at 474 nm and 570 nm.

An Electrochemical Approach for the Selective Detection of Cancer Metabolic Creatine Biomarker with Porous Nano-Formulated CMNO Materials Decorated Glassy Carbon Electrode.

The facile wet-chemical technique was used to prepare the low-dimensional nano-formulated porous mixed metal oxide nanomaterials (CuO.Mn2O3.NiO; CMNO NMs) in an alkaline medium at low temperature. Detailed structural, morphological, crystalline, and functional characterization of CMNO NMs were performed by X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS) analyses. An efficient and selective creatine (CA) sensor probe was fabricated by using CMNO NMs decorated onto glassy carbon electrode (GCE) as CMNO NMs/GCE by using Nafion adhesive (5% suspension in ethanol). The relation of current versus the concentration of CA was plotted to draw a calibration curve of the CMNO NMs/GCE sensor probe, which was found to have a very linear value (r2 = 0.9995) over a large dynamic range (LDR: 0.1 nM~0.1 mM) for selective CA detection. The slope of LDR by considering the active surface area of GCE (0.0316 cm2) was applied to estimate the sensor sensitivity (14.6308 µAµM-1 cm-2). Moreover, the detection limit (21.63 ± 0.05 pM) of CMNO MNs modified GCE was calculated from the signal/noise (S/N) ratio at 3. As a CA sensor probe, it exhibited long-term stability, good reproducibility, and fast response time in the detection of CA by electrochemical approach. Therefore, this research technique is introduced as a promising platform to develop an efficient sensor probe for cancer metabolic biomarker by using nano-formulated mixed metal oxides for biochemical as well as biomedical research for the safety of health care fields.

High Aspect Ratio Sub-Micrometer Channels Using Wet Etching: Application to the Dynamics of Red Blood Cell Transiting through Biomimetic Splenic Slits.

Nanoparticles delivering drugs, disseminating cancer cells, and red blood cells (RBCs) during splenic filtration must deform and pass through the sub-micrometer and high aspect ratio interstices between the endothelial cells lining blood vessels. The dynamics of passage of particles/cells through these slit-like interstices remain poorly understood because the in vitro reproduction of slits with physiological dimensions in devices compatible with optical microscopy observations requires expensive technologies. Here, novel microfluidic PDMS devices containing high aspect ratio slits with sub-micrometer width are molded on silicon masters using a simple, inexpensive, and highly flexible method combining standard UV lithography and anisotropic wet etching. These devices enabled revealing novel modes of deformations of healthy and diseased RBCs squeezing through splenic-like slits (0.6-2 × 5-10 × 1.6-11 µm3 ) under physiological interstitial pressures. At the slit exit, the cytoskeleton of spherocytic RBCs seemed to be detached from the lipid membrane whereas RBCs from healthy donors and patients with sickle cell disease exhibited peculiar tips at their front. These tips disappeared much slower in patients' cells, allowing estimating a threefold increase in RBC cytoplasmic viscosity in sickle cell disease. Measurements of time and rate of RBC sequestration in the slits allowed quantifying the massive trapping of spherocytic RBCs.

Soft, Wet-Chemical Synthesis of Metastable Superparamagnetic Hexagonal Close-Packed Nickel Nanoparticles in Different Ionic Liquids.

The microwave-induced decomposition of bis{N,N'-diisopropylacetamidinate}nickel(II) [Ni{MeC(NiPr)2 }2 ] or bis(1,5-cyclooctadiene)nickel(0) [Ni(COD)2 ] in imidazolium-, pyridinium-, or thiophenium-based ionic liquids (ILs) with different anions (tetrafluoroborate, [BF4 ]- , hexafluorophosphate, [PF6 ]- , and bis(trifluoromethylsulfonyl)imide, [NTf2 ]- ) yields small, uniform nickel nanoparticles (Ni NPs), which are stable in the absence of capping ligands (surfactants) for more than eight weeks. The soft, wet-chemical synthesis yields the metastable Ni hexagonal close-packed (hcp) and not the stable Ni face-centered cubic (fcc) phase. The size of the nickel nanoparticles increases with the molecular volume of the used anions from about 5 nm for [BF4 ]- to ≈10 nm for [NTf2 ]- (with 1-alkyl-3-methyl-imidazolium cations). The n-butyl-pyridinium, [BPy]+ , cation ILs reproducibly yield very small nickel nanoparticles of 2(±1) nm average diameter. The Ni NPs were characterized by high-resolution transmission electron microscopy (HR-TEM) and powder X-ray diffraction. An X-ray photoelectron spectroscopic (XPS) analysis shows an increase of the binding energy (EB ) of the electron from the Ni 2p3/2 orbital of the very small 2(±1) nm diameter Ni particles by about 0.3 eV to EB =853.2 eV compared with bulk Ni0 , which is traced to the small cluster size. The Ni nanoparticles show superparamagnetic behavior from 150 K up to room temperature. The saturation magnetization of a Ni (2±1 nm) sample from [BPy][NTf2 ] is 2.08 A m2 kg-1 and of a Ni (10±4 nm) sample from [LMIm][NTf2 ] it is 0.99 A m2 kg-1 , ([LMIm]=1-lauryl-3-methyl- imidazolium). The Ni NPs were active catalysts in IL dispersions for 1-hexene or benzene hydrogenation. Over 90 % conversion was reached under 5 bar H2 in 1 h at 100 °C for 1-hexene and a turnover frequency (TOF) up to 1330 molhexane (molNi )-1 h-1 or in 60 h at 100 °C for benzene hydrogenation and TOF=23 molcyclohexane (molNi )-1 h-1 .

How Size Determines the Value of Gold: Economic Aspects of Wet Chemical and Laser-Based Metal Colloid Synthesis.

Gold is one of the most valuable materials, and its monetary value is enhanced by size reduction from bullions to colloidal nanoparticles by a factor of 450. Wet-chemical reduction with subsequent centrifugation and pulsed laser ablation in liquids are frequently used for pure colloidal gold synthesis. Both methods provide similar physicochemical nanoparticle properties, but are very different synthesis techniques. However, the costs inherent to these methods are surprisingly seldom discussed. Both methods have in common that the labor effort poses the majority of synthesis costs. Besides an increase in batch size and mass concentration, especially an increase of the nanoparticle productivity via higher laser power and centrifugation capacity reduces synthesis costs if pilot- or industrial-scale applications are intended. In this case, laser-based synthesis is more economical if its productivity exceeds a break-even value of 550 mg h-1 , where the costs arising are limited by the metal costs. In contrast to industrial scale production, wet-chemical synthesis is more feasible for laboratory-scale applications, especially if the advantageous nanoparticle properties provided by laser ablation in liquids are not needed.

25 nm Single-Crystal Silicon Nanowires Fabricated by Anisotropic Wet Etching.

We report a top-down method for fabricating ultra-high aspect ratio single-crystal silicon nanowires. The fabrication method is based on the standard photolithography technique and anisotropic wet etching of the single-crystal silicon in KOH solution. SiO2 mask nanolines used for patterning single-crystal silicon nanowires are formed by the undercut etching of thin SiO2 layer in buffered hydrofluoric solution. The minimum width of the SiO2 mask nanolines are 50 nm. The length of SiO2 mask nanolines is 2 cm. The single-crystal silicon nanowires have been successfully transferred from the SiO2 mask nanolines by KOH anisotropic wet-chemical etching. The minimum width of the silicon nanowire has obtained to be 25 nm. The fabricated single-crystal silicon nanowires have trapezoidal and triangular cross sections, which are useful for applications in nanoelectronic and nanophotonic elements.

Luminescence characterization of Dy and Eu doped Na6 Mg(SO4 )4 phosphors.

A series of single-phase phosphors based on Na6 Mg(SO4 )4 (Zeff  = 11.70) doped with Dy and Eu was prepared by the wet chemical method. The photoluminescence (PL) and thermoluminescence (TL) properties of Dy3+ - and Eu3+ -activated Na6 Mg(SO4 )4 phosphors were investigated. The characteristic emissions of Dy3+ and Eu3+ were observed in the Na6 Mg(SO4 )4 host. The TL glow curve of the Na6 Mg(SO4 )4 :Dy phosphor consisted of a prominent peak at 234°C and a very small hump at 158°C. The TL sensitivity of the Na6 Mg(SO4 )4 :Dy phosphor was found to be four times less than the commercialized CaSO4 :Dy phosphor. The TL dose-response of the Na6 Mg(SO4 )4 :Dy phosphor was studied from a dose range of 5-10 kGy and the linear dose-response was observed up to 1 kGy which is good for a microcrystalline phosphor. Trapping parameters for both the samples were calculated using the Initial Rise and Chen's peak shape methods.