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Highlights Blue micro-light-emitting diodes (μLED)-integrated gas sensors were fabricated as monolithic structure by directly loading sensing materials onto the μLED. SnO2 nanoparticles are activated by blue μLED and exhibit outstanding sensitivity to NO2 at μ-Watt power levels. Noble metal (Au, Pd, Pt)-decorated SnO2 showed the tunable gas selectivity for 4 target gases under blue light illumination.

Research on Hanwoo cattle has focused on the pleomorphic adenoma gene (PLAG) family, vital for traits like growth and carcass quality. Single nucleotide polymorphisms (SNPs) within this gene family profoundly impact economic traits. At the cellular level, energy and protein sources, notably glucose and lysine, crucially regulate muscle satellite cell (MSC) growth and differentiation.This study delved into how varied glucose and lysine levels affect gene expression patterns in Hanwoo MSC. MSC from 9 Hanwoo, aged 29–36 months, categorized into 3 PLAG1 genotypes (GG, GC, CC), were treated with six combinations of glucose (5.5 and 25 mM) and lysine (2, 4, and 8 mM). Analysis of myogenic and adipogenic genes linked to meat quality and quantity ensued.The GG genotype displayed superior dressed percentage, yield grade, and marbling score, hinting at genotype-associated carcass characteristic disparities. In cell culture, gene expression generally rose with lysine addition to high glucose in the GG group. Contrarily, significant differences across all treatments in the GC genotype suggested distinct responses. Significant effects of genotype, glucose, and lysine on cell proliferation-related gene expression were noted. Highest mRNA expression for MyoD, MyoG, and FASN occurred in the CC genotype, while Myf5 and Pax7 expression peaked in the GG genotype. Glucose significantly influenced Pax7 and FASN expression, while lysine positively impacted MyoD and MyoG genes. Notable interactions, especially in Genotype × Lysine, influenced MyoD, Myf5, and Pax7 expression, highlighting complex relationships in cell proliferation. Regarding cell differentiation, Pax7 expression was highest in PLAG1 GG type. High glucose prompted wider myotubes, while lower lysine concentrations slightly favored cell differentiation. Correspondingly, MyoG expression decreased with higher lysine levels.This study furnishes insights into lysine and glucose supplementation effects on bovine MSC proliferation and differentiation, considering PLAG1 genotype influence. It offers valuable data for beef production system establishment and optimizing cell-based food production.

Abstract Monitoring taste‐inducing ions and molecules continuously in liquids or solutions is of great considerable matter for the realization of the electronic tongue (E‐tongue). Particularly from the five major tastes, the highly selective, sensitive detection of Na+ in real‐time is prioritized. Prioritization is due to the saltiness of food is the key ingredient in most meals. Nevertheless, existing Na+ detecting devices have relatively low performances of selectivity, sensitivity, and lack of on–off functions. Additionally, conventional devices significantly deteriorate in capacity due to repetitive usage or lifetime shortage by degradation of the sensing material. Herein, a graphene‐based channel was rationally designed by the facile decoration of Calix[4]arene and Nafion to address this issue. They act as a receptor and a molecular sieve, respectively, to enhance selectivity and sensitivity and elongate the life expectancy of the device. This device was merged with a microfluidic channel to control the injection and withdrawal of solutions to fulfill dynamic on–off functions. The fabricated device has highly selective, sensitive Na+ detection properties compared to other 10 molecule/ionic species. Dynamic on–off functions of the device were available, also possesses a long lifespan of at least 220 days. Additionally, it can precisely discriminate real beverages containing Na+, which can be observed by principal component analysis plot. These features offer the possibility of ascending to a platform for E‐tongues in near future.

Abstract The development of new heterostructures with high photoactivity is a breakthrough for the limitation of solar‐driven water splitting. Here, we first introduce indium oxide (In2O3) nanorods (NRs) as a novel electron transport layer for bismuth vanadate (BiVO4) with a short charge diffusion length. In2O3 NRs reinforce the electron transport and hole blocking of BiVO4, surpassing the state‐of‐the‐art photoelectrochemical performances of BiVO4‐based photoanodes. Also, a tannin–nickel–iron complex (TANF) is used as an oxygen evolution catalyst to speed up the reaction kinetics. The final TANF/BiVO4/In2O3 NR photoanode generates photocurrent densities of 7.1 mA cm−2 in sulfite oxidation and 4.2 mA cm−2 in water oxidation at 1.23 V versus the reversible hydrogen electrode. Furthermore, the “artificial leaf,” which is a tandem cell with a perovskite/silicon solar cell, shows a solar‐to‐hydrogen conversion efficiency of 6.2% for unbiased solar water splitting. We reveal significant advances in the photoactivity of TANF/BiVO4/In2O3 NRs from the tailored nanostructure and band structure for charge dynamics.

Abstract Dedications to achieve the highly efficient metal oxide semiconductor for the photoelectrochemical water splitting system have been persisted to utilize the TiO2 as the promising photoanode material. Herein, we report notable progress for nanostructured TiO2 photoanodes using facile sequential one-pot hydrothermal synthesis and annealing in hydrogen. A photocurrent density of 3.04 mA·cm−2 at 1.23 V vs. reversible hydrogen electrode was achieved in TiO2 nanorod arrays annealed in hydrogen ambient, which is approximately 4.25 times higher than that of pristine TiO2 annealed in ambient air. 79.2% of incident photon-to-current efficiency at 380 nm wavelength demonstrates the prominence of the material at the near-UV spectral range region and 100 h chronoamperometric test exhibits the stability of the photoanode. Detailed studies regarding crystallinity, bandgap, and elemental analysis provide the importance of the optimized annealing condition for the TiO2-based photoanodes. Water contact angle measurement displays the effect of hydrogen annealing on the hydrophilicity of the material. This study clearly demonstrates the marked improvement using the optimized hydrogen annealing, providing the promising methodologies for eco-friendly mass production of water splitting photoelectrodes. Graphical Abstract

Abstract Direct consideration for both, the catalytically active species and the host materials provides highly efficient strategies for the architecture design of nanostructured catalysts. The conventional wet chemical methods have limitations in achieving such unique layer-by-layer design possessing one body framework with many catalyst parts. Herein, an innovative physical method is presented that allows the well-regulated architecture design for an array of functional nanocatalysts as exemplified by layer-by-layer adornment of Pd nanoparticles (NPs) on the highly arrayed silica nanorods. This spatially confined catalyst exhibits excellent efficiency for the hydrogenation of nitroarenes and widely deployed Suzuki cross-coupling reactions; their facile separation from the reaction mixtures is easily accomplished due to the monolithic structure. The generality of this method for the introduction of other metal source has also been demonstrated with Au NPs. This pioneering effort highlights the feasibility of physically controlled architecture design of nanostructured catalysts which may stimulate further studies in the general domain of the heterogeneous catalytic transformations.

Abstract Although bismuth vanadate (BiVO4) has been promising as photoanode material for photoelectrochemical water splitting, its charge recombination issue by short charge diffusion length has led to various studies about heterostructure photoanodes. As a hole blocking layer of BiVO4, titanium dioxide (TiO2) has been considered unsuitable because of its relatively positive valence band edge and low electrical conductivity. Herein, a crystal facet engineering of TiO2 nanostructures is proposed to control band structures for the hole blocking layer of BiVO4 nanodots. We design two types of TiO2 nanostructures, which are nanorods (NRs) and nanoflowers (NFs) with different (001) and (110) crystal facets, respectively, and fabricate BiVO4/TiO2 heterostructure photoanodes. The BiVO4/TiO2 NFs showed 4.8 times higher photocurrent density than the BiVO4/TiO2 NRs. Transient decay time analysis and time-resolved photoluminescence reveal the enhancement is attributed to the reduced charge recombination, which is originated from the formation of type II band alignment between BiVO4 nanodots and TiO2 NFs. This work provides not only new insights into the interplay between crystal facets and band structures but also important steps for the design of highly efficient photoelectrodes.

Abstract Two-dimensional MoS2 film can grow on oxide substrates including Al2O3 and SiO2. However, it cannot grow usually on non-oxide substrates such as a bare Si wafer using chemical vapor deposition. To address this issue, we prepared as-synthesized and transferred MoS2 (AS-MoS2 and TR-MoS2) films on SiO2/Si substrates and studied the effect of the SiO2 layer on the atomic and electronic structure of the MoS2 films using spherical aberration-corrected scanning transition electron microscopy (STEM) and electron energy loss spectroscopy (EELS). The interlayer distance between MoS2 layers film showed a change at the AS-MoS2/SiO2 interface, which is attributed to the formation of S–O chemical bonding at the interface, whereas the TR-MoS2/SiO2 interface showed only van der Waals interactions. Through STEM and EELS studies, we confirmed that there exists a bonding state in addition to the van der Waals force, which is the dominant interaction between MoS2 and SiO2. The formation of S–O bonding at the AS-MoS2/SiO2 interface layer suggests that the sulfur atoms at the termination layer in the MoS2 films are bonded to the oxygen atoms of the SiO2 layer during chemical vapor deposition. Our results indicate that the S–O bonding feature promotes the growth of MoS2 thin films on oxide growth templates.

Abstract The detection of ions and molecules in liquids has been receiving considerable attention for the realization of the electronic tongue. Solution-gated field-effect transistors (SFETs) with high sensitivity are useful for detecting ions and molecules by reading electrical transconductance. However, to date, ionic and molecular sensors that employ SFETs have limitations, such as the lack of a dynamic on–off function and low selectivity. In this study, we evaluate rationally designed graphene SFETs as pH and glucose-selective sensors. The integration of the microfluidic channel to the graphene SFET exhibits dynamic on–off functions by controlling injection and withdrawal of solutions. The graphene SFET device exhibits high pH and glucose selectivity when coated with Nafion as a molecular sieve and Au-decorated nanoparticles as receptors, respectively. The dynamic on–off functions and high selectivity of SFETs with tailored graphene channels have a high potential for advancing as a platform for electronic tongues by integrating the separate SFETs as an array for simultaneous sensing of multiple targets.

Highlights MoP nanorod-array catalysts were directly synthesized on graphene passivated silicon photocathodes without secondary phase. Mo-O-C covalent bondings and energy band bending at heterointerfaces facilitate the electron transfer to the reaction sites. Numerous catalytic sites and drastically enhanced anti-reflectance of MoP nanorods contribute to the high solar energy conversion efficiency. Abstract Transition metal phosphides (TMPs) and transition metal dichalcogenides (TMDs) have been widely investigated as photoelectrochemical (PEC) catalysts for hydrogen evolution reaction (HER). Using high-temperature processes to get crystallized compounds with large-area uniformity, it is still challenging to directly synthesize these catalysts on silicon photocathodes due to chemical incompatibility at the heterointerface. Here, a graphene interlayer is applied between p-Si and MoP nanorods to enable fully engineered interfaces without forming a metallic secondary compound that absorbs a parasitic light and provides an inefficient electron path for hydrogen evolution. Furthermore, the graphene facilitates the photogenerated electrons to rapidly transfer by creating Mo-O-C covalent bondings and energetically favorable band bending. With a bridging role of graphene, numerous active sites and anti-reflectance of MoP nanorods lead to significantly improved PEC-HER performance with a high photocurrent density of 21.8 mA cm−2 at 0 V versus RHE and high stability. Besides, low dependence on pH and temperature is observed with MoP nanorods incorporated photocathodes, which is desirable for practical use as a part of PEC cells. These results indicate that the direct synthesis of TMPs and TMDs enabled by graphene interlayer is a new promising way to fabricate Si-based photocathodes with high-quality interfaces and superior HER performance. Graphic Abstract

Abstract Rechargeable metal-ion batteries are considered promising electric storage systems to meet the emerging demand from electric vehicles, electronics, and electric grids. Thus far, secondary Li-ion batteries (LIBs) have seen great advances in terms of both their energy and their power density. However, safety issues remain a challenge. Therefore, rechargeable Al-ion batteries (AIBs) with a highly reliable safety advantage and active electrochemical performances have gathered intensive attention. However, the common issue for these two metal-ion batteries is the lack of cathode materials. Many advanced electrode materials reported provide greatly enhanced electrochemical properties. However, their inherent disadvantages—such as complicated fabrication procedures, restricted manufacturing parameters, and the requirement of expensive instruments—limits their potential for further applications. In this work, we demonstrate the high electrochemical activity of the lanthanide element, Sm, towards storing charges when used in both LIBs and AIBs. Lanthanide elements are often overlooked; however, they generally have attractive electrochemical properties owing to their unpaired electrons. We employed starch as both a low-cost carbon source and as a three-dimensional support for Sm metal nanoparticles. The composite product is fabricated using a one-pot wet-chemical method, followed by a simultaneous carbonization process. As a result, highly improved electrochemical properties are obtained when it is used as a cathode material for both LIBs and AIBs when compared to bare starch-derived C. Our results may introduce a new avenue toward the design of high-performance electrode materials for LIBs and AIBs.

Abstract Although lithium‐air batteries (LABs) are considered the promising alternative of existing lithium–ion batteries owing to their high energy density of 11 680 W h kg−1, their practical applications are limited by the technical issues, such as unstable solid electrolyte interface and dendrite formation from metal anode and insufficient bifunctional activities and durability from cathode catalyst. In order to resolve these bottlenecks, carbon nanostructures have been investigated owing to their high surface area, excellent electrical conductivity, electrochemical stability, and various modification chemistries. Herein, we comprehensively review a recent progress on the design of carbon nanostructures for their applications into metal hosts, protection layers, and bifunctional electrocatalysts of LABs. The correlation between the crystalline, electronic, porous, and chemical structures and the electrochemical properties of carbon nanomaterials are discussed depending on their classification and characteristics. Various chemical modifications, such as morphological control, hierarchical architecturing, heteroatom incorporation, and the formation of composites, for the improved electrochemical performances of anode and cathode will be also addressed. Furthermore, we deal with the perspectives for the ongoing obstruction and future guidance.

Abstract A low-cost nanocomposite catalyst containing copper oxide (CuO) nanoparticles (NPs) on graphene oxide (GO) was fabricated by a facile hydrothermal self-assembly process. The segregated CuO NPs and GO exhibited negligible catalytic activities for the reduction of nitroaromatics. However, their hybrid composite accomplished facile reduction with high conversions for several substituted nitroaromatics in aqueous NaBH4 solution; synergetic coupling effect of CuO NPs with GO in the nanocomposite catalyst provided excellent catalytic activity. The nanocomposite catalyst could be separated from the reaction mixture and recycled consecutively.

Abstract One of the well‐known strategies for achieving high‐performance light‐activated gas sensors is to design a nanostructure for effective surface responses with its geometric advances. However, no study has gone beyond the benefits of the large surface area and provided fundamental strategies to offer a rational structure for increasing their optical and chemical performances. Here, a new class of UV‐activated sensing nanoarchitecture made of highly periodic 3D TiO2, which facilitates 55 times enhanced light absorption by confining the incident light in the nanostructure, is prepared as an active gas channel. The key parameters, such as the total 3D TiO2 film and thin‐shell thicknesses, are precisely optimized by finite element analysis. Collectively, this fundamental design leads to ultrahigh chemoresistive response to NO2 with a theoretical detection limit of ≈200 ppt. The demonstration of high responses with visible light illumination proposes a future perspective for light‐activated gas sensors based on semiconducting oxides.

Summary: Selecting moderate semiconducting materials for photoelectrochemical (PEC) cells is essential to achieve high solar-energy conversion. Despite the advantageous features of silicon, such as earth abundance and narrow band gap, silicon suffers from severe photocorrosion. Here, heterogeneous nickel-based catalysts produced via electrodeposition are investigated to expedite water oxidation and protect the silicon from corrosion. The morphology of the catalysts and their PEC performances are demonstrated in detail. Synergistic Ni nanoparticles (NPs)/Ni(OH)2/n-Si photoanode shows a high photocurrent density of 29.6 mA cm−2 at 1.23 V versus RHE and operates over 140 h. Owing to the insufficient photovoltage generated by a single photoanode, we introduce a perovskite/Si tandem solar cell as a voltage supplier. The fabricated wired tandem device shows a photocurrent density of 9.8 mA cm−2, corresponding to a solar-to-hydrogen (STH) conversion efficiency of 12% without external bias. Our work may present a promising pathway toward a design of spontaneous energy conversion devices.

In this work, CsPbBr3 and PbSe nanocomposites were synthesized to protect perovskite material from self-enlargement during reaction. UV absorption and photoluminescence (PL) spectra indicate that the addition of Se into CsPbBr3 quantum dots modified the electronic structure of CsPbBr3, increasing the band gap from 2.38 to 2.48 eV as the Cs:Se ratio increased to 1:3. Thus, the emission color of CsPbBr3 perovskite quantum dots was modified from green to blue by increasing the Se ratio in composites. According to X-ray diffraction patterns, the structure of CsPbBr3 quantum dots changed from cubic to orthorhombic due to the introduction of PbSe at the surface. Transmission electron microscopy and X-ray photoemission spectroscopy confirmed that the atomic distribution in CsPbBr3/PbSe composite clusters is uniform and the composite materials were well formed. The PL intensity of a CsPbBr3/PbSe sample with a 1:1 Cs:Se ratio maintained 50% of its initial intensity after keeping the sample for 81 h in air, while the PL intensity of CsPbBr3 reduced to 20% of its initial intensity. Therefore, it is considered that low amounts of Se could improve the stability of CsPbBr3 quantum dots.

Photoelectrochemical water splitting is considered as a long-term solution for the ever-increasing energy demands. Various strategies have been employed to improve the traditional TiO2 photoanode. In this study, TiO2 nanorods were decorated by graphitic carbon nitride (C3N4) derived from different precursors such as thiourea, melamine, and a mixture of thiourea and melamine. Photoelectrochemical activity of TiO2/C3N4 photoanode can be modified by tuning the number of precursors used to synthesize C3N4. C3N4 derived from the mixture of melamine and thiourea in TiO2/C3N4 photoanode showed photocurrent density as high as 2.74 mA/cm2 at 1.23 V vs. RHE. C3N4 synthesized by thiourea showed particle-like morphology, while melamine and melamine with thiourea derived C3N4 yielded two dimensional (2D) nanosheets. Nanosheet-like C3N4 showed higher photoelectrochemical performance than that of particle-like nanostructures as specific surface area, and the redox ability of nanosheets are believed to be superior to particle-like nanostructures. TiO2/C3N4 displayed excellent photostability up to 20 h under continuous illumination. Thiourea plays an important role in enhancing the photoelectrochemical performance of TiO2/C3N4. This study emphasizes the fact that the improved photoelectrochemical performance can be achieved by varying the precursors of C3N4 in TiO2/C3N4 heterojunction. This is the first report to show the influence of C3N4 precursors on photoelectrochemical performance in TiO2/C3N4 systems. This would pave the way to explore different precursors influence on C3N4 with respect to the photoelectrochemical response of TiO2/C3N4 heterojunction photoanode.

Transition metal dichalcogenides (TMDs) have been considered as one of the most promising electrocatalysts for the hydrogen evolution reaction (HER). Many studies have demonstrated the feasibility of significant HER performance improvement of TMDs by constructing composite materials with Ni-based compounds. In this work, we prepared Ni3Se4@MoSe2 composites as electrocatalysts for the HER by growing in situ MoSe2 on the surface of Ni3Se4 nanosheets. Electrochemical measurements revealed that Ni3Se4@MoSe2 nanohybrids are highly active and durable during the HER process, which exhibits a low onset overpotential (145 mV) and Tafel slope (65 mV/dec), resulting in enhanced HER performance compared to pristine MoSe2 nanosheets. The enhanced HER catalytic activity is ascribed to the high surface area of Ni3Se4 nanosheets, which can both efficiently prevent the agglomeration issue of MoSe2 nanosheets and create more catalytic edge sites, hence accelerate electron transfer between MoSe2 and the working electrode in the HER. This approach provides an effective pathway for catalytic enhancement of MoSe2 electrocatalysts and can be applied for other TMD electrocatalysts.

A century after its first synthesis in 1914, black phosphorus has been attracting significant attention as a promising two-dimensional material in recent years due to its unique properties. Nowadays, with the development of its exfoliation method, there are extensive applications of black phosphorus in transistors, batteries and optoelectronics. Though, because of its hardship in mass production and stability problems, the potential of the black phosphorus in various fields is left unexplored. Here, we provide a comprehensive review of crystal structure, electronic, optical properties and synthesis of black phosphorus. Recent research works about the applications of black phosphorus is summarized. Among them, the possibility of black phosphorous as a solar water splitting photocatalyst is mainly discussed and the feasible novel structure of photocatalysts based on black phosphorous is proposed.