In order to achieve a high quantum efficiency, doping crystals with appropriate elements such as sodium cations (ref. [8]) to reduce electronic dimension is a useful method. [5,8] However, doping also tends to cause nonradiation recombination loss. [13] Therefore, a reliable and promising way is to synthesize high-quality inorganic metal halide single crystal (SC) with natural lowdimensional structure to realize stable and high quantum efficiency white-light illumination application.In this work, we successfully synthesized 1D CsCu 2 I 3 SC by replacing toxic Pb with eco-friendly and abundant Cu, and organic molecules with large-radius Cs. [12,13] The "one dimension" we noted here is localized dimension of electron. [14] Through density functional theory (DFT) calculation, in 1D CsCu 2 I 3 SC, [Cu 2 I 3 ] − octahedra contributes most electronic states, and Cs + only forms a 1D electronic structure with isolated [Cu 2 I 3 ] − in 2D direction. Therefore, CsCu 2 I 3 SC obtains a high photoluminescence quantum yield (PLQY ≈15.7%) of the IWE at room temperature. [2] We also calculated that the crystal has a high radiation recombination rate which is owning to the 1D localized electronic structure, and this rate is the key to its high PLQY. [15,16] Under a strong injection and atmospheric environment, the PL intensity of all-inorganic CsCu 2 I 3 SC only decays about 5% after 750 min ( Figure S5, Supporting Information). This excellent stability demonstrates that the all-inorganic CsCu 2 I 3 SC possesses a great prospect in high-efficiency lighting applications.High-quality CsCu 2 I 3 SCs were synthesized by antisolvent infiltration method. [17,18] Cesium iodide and cuprous (I) iodide in certain ratio were dissolved in dimethyl formamide (DMF)dimethyl sulfoxide (DMSO) (4:1) to obtain a saturated solution. Then, methanol (antisolvent) was slowly dropped into the saturated solution to form a white precipitate (the white precipitate quickly dissolved again) until it no longer dissolved. The solution was filtered and then placed in a beaker with methanol atmosphere to grow crystals. Several days later, centimeter-scale high-quality CsCu 2 I 3 SCs were obtained (refer to the Supporting information and the Experimental Section for more details). Figure 1a shows an optical image of a rod-shaped CsCu 2 I 3 SCs excited by ultraviolet light. The SC has a size of about 10 mm × 1.5 mm, being colorless and transparent at room temperature but having strong white-light emission under ultraviolet light. Crystal structure of the CsCu 2 I 3 SC was obtained through single-crystal X-ray diffraction (SCXRD) test (Figure 1b,c), which belongs to orthorhombic system. The 1D Energy-saving white lighting from the efficient intrinsic emission of semiconductors is considered as a next-generation lighting source. Currently, white-light emission can be composited with a blue light-emitting diode and yellow phosphor. However, this solution has an inevitable light loss, which makes the improvement of the energy utilization efficiency more difficult. T...

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This review introduces the developments in β-Ga2O3 materials growth and solar blind UV photodetectors in the last decade, summarizes their advantages and potential for improvement, and puts forward some suggestions for actual application requirements.

Biofuel cells (BFCs) utilize biocatalysts such as enzymes and microorganisms for the conversion of chemical energy into electrical energy. [1][2][3][4] These BFCs represent a new kind of energy-conversion technology that is distinct from conventional fuel cells, such as H 2 /O 2 and methanol/O 2 fuel cells, mainly in that they can operate under moderate conditions, such as in mild media and at ambient temperatures. Moreover, compared with the noble-metal catalysts used in conventional fuel cells, the biocatalysts used in the BFCs are more efficient and selective toward the biomass. More remarkably, the biomass consumed by the BFCs, such as glucose and oxygen, is generally endogenous to biological systems. As such, BFCs are envisaged to be able to power the bioelectronics in vivo, finding uses in systems such as implantable biosensors or pacemakers in the human body. [5][6][7][8] These striking properties and the potential applications of BFCs have evoked intensive interest in the basic study and development of BFCs in recent years. [9][10][11][12][13][14] It is known that carbon nanotubes (CNTs), a new kind of carbon-based nanomaterial, possess unique structural and electronic properties, and are finding striking applications in various research and industrial fields, [15][16][17][18][19][20][21] including electrochemistry. [22][23][24] In addition to their excellent electrochemical properties, CNTs have several characteristics that make them very suitable for the development of enzymatic BFCs. For example, CNTs bear graphene sidewalls that are chemically inert and highly hydrophobic, with a dense p-p stacking. Such a property essentially makes CNTs well suited as a support for the redox mediators [25][26][27] generally employed for shuttling the electron transfer of biocatalysts, for example enzymes and proteins, or for the conversion and oxidation of the NADH (nicotinamide adenine dinucleotide with hydrogen) cofactor when dehydrogenases are used as the anode biocatalysts. Moreover, as demonstrated recently, [28][29][30] the use of CNTs could largely facilitate the direct electron transfer of the enzymes and proteins. On the other hand, CNTs have a good conductivity (depending on the sort of CNTs used) and a high surface area to weight ratio (ca. 300 m 2 g -1 ) [31] as well as the ability to form a 3D matrix that can be used for both enzyme immobilization and electrode reactions.In this Communication we demonstrate the first singlewalled carbon nanotube (SWNT)-based glucose/O 2 biofuel cell with glucose dehydrogenase (GDH) as the anode biocatalyst for the oxidation of glucose, with NAD + as the cofactor and laccase (from Trametes versicolor) as the cathode biocatalyst for O 2 reduction (Scheme 1). On the SWNT anode, methylene blue (MB) was adsorbed through the interactions between MB and SWNTs, as described in our earlier work.[25]Although the formed MB-SWNT adsorptive adduct exhibits excellent electrochemical properties and a good stability, its activity for redox-mediating the oxidation of NADH was found to be...