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[Display omitted] • Silicon nanopillar arrays(Si-NPAs) with high light absorption are used as substrates for photodetectors to improve light utilization. • Large-area coating deposition of layer less MoS 2 on the surface of three-dimensional silicon nanopillar arrays. • Combining MoS 2 with silicon to form a heterojunction reduces the silicon surface compound, boosting the photocurrent and reducing the dark current. • The use of reticulated, high-transmittance conductive thin Ag nanowires as the upper electrode provides multiple paths for electron transport without affecting light absorption and enhances the photodetector response speed. Two-dimensional MoS 2 has shown great potential in the photoelectric field because of its excellent optical and electrical properties. However, the performance of MoS 2 -based planar photodetector is constrained by the short transmission path and limited light absorption capacity of the planar thin layer of MoS 2. In this paper, highly sensitive MoS 2 /silicon nanopillar arrays(Si-NPAs) photodetector by coating the surface of silicon nanotrap light array with MoS 2. The interaction between light waves and silicon nanopillars and MoS 2 is significantly enhanced by the Fabry-Pérot-enhanced Mie resonance between pillars as well as the multiple reflection. In the meantime, a Van der Waals heterojunction is constructed between the MoS 2 and Si-NPAs coated across a large area. This is beneficial to address the poor performance of traditional two-dimensional photodetectors in light absorption and prevent the surface recombination of silicon-based photodetectors. According to the research results,the detector has 4.15 × 102 excellent rectification characteristics and 1.93 × 103 high switch ratio, and the photovoltaic effect is significant. The average external quantum efficiency of MoS 2 /Si-NPAs photodetector is 61.2% in the visible and near infrared bands, which is twice that of MoS 2 /planar silicon photodetector. At 850 nm, the responsiveness of the MoS 2 /Si NPAs photodetector is 0.48 A/W. the detection rate reaches 1.058 × 1012cm·Hz 1/2 W−1, which is 10.7 times higher than that of MoS 2 /planar silicon photodetector. To sum up, this study contributes a fresh idea to the design and application of high-performance devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchical Ti-doped Co 3 O 4 miscrospheres with abundant oxygen defects was prepared. • Ti-doped Co 3 O 4 miscrospheres with more oxygen vacancies had a response of 64.9 to 50 ppm xylene. • Ti-doped Co 3 O 4 miscrospheres with more defect oxygen ions had a response of 57.2 to 50 ppm toluene. • The Ti-doped Co 3 O 4 miscrospheres showed excellent selectivity, repeatability, and stability. Vast efforts have been made to develop high-performance gas sensing materials for the detection of harmful volatile organic compounds (VOCs) like toluene and xylene. However, it is challenging to selectively detect toluene and xylene simultaneously. Herein, the hierarchical Ti-doped cobalt layered hydroxides miscrospheres were synthesized first and sintered at high temperature consequently to prepare hierarchical Ti-doped Co 3 O 4 miscrospheres. The incorporation of Ti into the lattice of Co 3 O 4 decreased the crystal sizes and crystallinity, resulting in higher specific surface area and more oxygen defects. Interestingly, the 3 at.% Ti-doped Co 3 O 4 miscrospheres sintered at 450 °C exhibited the highest response of 64.9 to 50 ppm of xylene at 210 °C, while the 1 at.% Ti-doped Co 3 O 4 miscrospheres calcined at 500 °C displayed the highest response of 57.2 to 50 ppm of toluene at 240 °C, which were about 11.8 and 7.8 times higher in comparison with pristine Co 3 O 4. The different selectivity of Ti-doped Co 3 O 4 to toluene and xylene arises from the different amounts of oxygen vacancies and defect oxygen ions. The obtained Ti-doped Co 3 O 4 microspheres also showed the merits of good selectivity, repeatability and long-term stability, indicating the promising applications of Ti-doped Co 3 O 4 miscrospheres in the detection of toluene and xylene. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel microcapsule system was constructed for sensitive detection of H 2 O 2 at high temperature. • The microcapsules were based on PCM core, electroactive layer, and surface-immobilized catalase. • The microcapsules show a high latent heat capacity for thermal regulation of H 2 O 2 biosensor. • The biosensor exhibits an enhanced ability for H 2 O 2 determination due to in-situ thermal management. • The biosensor finds great potential for detecting the H 2 O 2 level over a broad working temperature range. To address the deterioration in electrochemical biosensing detection of hydrogen peroxide (H 2 O 2) caused by enzymatic inactivation in high-temperature environments, we have developed a novel type of catalase-immobilized electroactive phase-change microcapsules based on a phase change material (PCM) core, an SiO 2 shell, and a poly(3,4 -ethylenedioxythiophene)/Au nanocomposite layer with the surface-immobilized catalase. The microcapsules not only show a well-defined core–shell microstructure with the desired chemical compositions, but also present a high latent heat capacity of over 130 J/g for thermal regulation. An electrochemical biosensor was established using the microcapsule-modified working electrode to obtain a high electrochemical response to H 2 O 2 through combining the highly electroactive layer with covalently bonded catalase. The developed biosensor achieved an enhanced electrochemical biosensing response to H 2 O 2 through regulating the microenvironmental temperature surrounding the working electrode by the latent heat release of its PCM core to prevent enzymatic inactivation at high temperature. Compared to conventional H 2 O 2 biosensors without thermal management by PCMs, the developed biosensor exhibits a higher sensitivity of 42.85 µA·mM−1·cm−2 and a lower detection limit of 3.56 µM at a high working temperature of 50 °C. The developed biosensor has found practical applications for sensitive detection and accurate determination of H 2 O 2 level in real food and biological samples over a wide temperature range. [ABSTRACT FROM AUTHOR]

[Display omitted] • Titania oxide with a shrubby morphology was prepared on carbon cloth to trigger SERS "hotspots" with a high-density. • The structure-dependent SERS and photocatalysis performance were investigated for as-prepared CC/TiO 2 /Ag hybrid substrates. • An actual detection of quercetin in teas was achieved by the self-cleaning SERS substrate. Constructing of plasmonic substrate with the capability of detecting nutritional food quality will soon be emerged as the frontier research directions with broad prospects in surface-enhanced Raman scattering (SERS) technology ascribed to an improvement of living standards. Herein, a novel TiO 2 framework with a shrubby morphology was successfully constructed on carbon cloth (CC) matrix to trigger significantly enhanced electromagnetic "hotspots" after dense Ag network with numerous sharp corners and edges was formed by a photo-induced reduction. Particularly, the structure-dependent optical performance was investigated for these as-prepared CC/TiO 2 /Ag hybrid substrates, screening out an optimal one with an enhancement factor of 6.38 × 107. Regarding a prominent photocatalytic efficiency ascribed to the high electron-hole separation efficiency assisted by the CC matrix and Ag decoration, a recyclable SERS-based monitoring of quercetin (QR) was achieved in teas, demonstrating recovery values distributed from 88.9 % to 106.4 %. The strategy proposed here opened a new way to create high-density "hotspots" for multifunctional SERS substrates, which might play a crucial role in food quality monitoring applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultra-high quality O/N co-doped graphene with high surface area is derived from biomass. • Intrinsic Ca-containing species in biomass transfers into CaO during pyrolysis process. • The imbedded CaO functions as template and catalyst to generate hierarchical porous graphene. • KOH effectively facilitated the graphene formation and enhanced the porosity. • Biomass-based graphene exhibits excellent supercapacitive performance. Ultrahigh-quality graphene with structural hierarchy has been successfully fabricated through a novel and effective bioinspired in situ self-catalyzing strategy with camphor leaves as a renewable carbon source. The intrinsic Ca-containing species in biomass transfers into CaO via the intermediate of CaCO 3 during the pyrolysis process, and the finally imbedded CaO functions as in situ hard template and catalyst to generate hierarchical structure and construct the graphitic structure. The utilization of KOH effectively facilitated the graphene formation and enhanced the porosity of the carbon materials. The resultant graphene possesses many advantages for supercapacitor application, including large surface area, hierarchical porosity (crosslinked micro/meso/macroporous vacancies), well-organized graphene layers and favorable dually co-doping of O/N, thereby contributing to rapid charge transportation on the electrode/electrolyte interface, fast diffusion of electrolyte ions and high conductivity. When directly used as supercapacitor electrode (without the mixture of any conductive agent), as-produced graphene exhibited a specific capacitance of 397F/g at a current density of 1.0 A/g with a high rate retention of 74% from 1 to 20 A/g in a three-electrode system with 6 M KOH aqueous electrolyte. The high-quality graphene prepared from biomass via a readily scalable method opened up new vision towards high performance applications in energy storage and conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • We fabricated a type of phase-change microcapsules with surface-constructed Ni(OH) 2 nanoflowers. • The resultant microcapsules show a well-defined layer-by-layer core-shell microstructure. • The microcapsules achieve a significant enhancement in heat transfer and thermal response. • The microcapsules exhibit a satisfactory latent-heat capacity and stable thermal energy-storage process. • This study offers a new design of phase-change microcapsules with fast thermal response. A phase-change microcapsule system based on an n -docosane core and SiO 2 /nanostructural Ni(OH) 2 layer-by-layer shell was designed with the aim to enhance the heat transfer and thermal response capability of phase-change microcapsules. This system was fabricated through emulsion-templated interfacial polycondensation to form a SiO 2 / n -docosane microcapsule system, followed by anchoring Ni(OH) 2 nanoflowers on the surface of the SiO 2 shell via structure-directed interfacial precipitation. The resultant microcapsule system achieved a satisfactory latent heat-storage capacity of around 130 J/g with high energy-storage efficiency over 99%. Compared to conventional SiO 2 / n -docosane phase-change microcapsules, this microcapsule system not only presents high thermal conductivity, rapid heat transfer rate, good leakage prevention capability, high heat charging-discharging stability, but also exhibits a good phase-change reversibility and resilience ability to perform repetitious solid-liquid phase transformations. The combination of traditional phase-change microcapsules with a nanostructural Ni(OH) 2 outer layer results in a significant enhancement in heat transfer, which makes the system a fast thermal response ability to satisfy a variety of applications where fast and stable thermal energy storage/release is required. Through constructing the Ni(OH) 2 nanoflowers on the surface of conventional phase-change microcapsules, this study offers a promising strategy for the design and fabrication of high-performance phase-change microcapsules with fast thermal response. [ABSTRACT FROM AUTHOR]

[Display omitted] • A two-dimensional composite semiconductor was developed by in-situ growing reticular ZIF-67 film upon black phosphorus (BP) nanosheets. • An attractive synergistic chemical enhancement was triggered attributed to the efficient continued charge transfer process in the BP/ZIF-67 system. • A selective SERS enhancement of food additive molecules with different orbital structures was achieved. Semiconductor-based surface-enhanced Raman scattering (SERS) dependent on chemical mechanism has shown favorable selective enhancement and recognition capabilities. However, the limited Raman enhancement capability of conventional semiconductor-based still remains a great challenge in the effective monitoring of trace molecules in a practical complex environment. In this context, a novel two-dimensional composite semiconductor substrate was developed by in-situ growing reticular ZIF-67 mesoporous film upon black phosphorus (BP) nanosheets. An attractive synergistic chemical enhancement was triggered attributed to the efficient continued charge transfer process in the BP/ZIF-67 system. Particularly, a selective SERS enhancement of food additive molecules with different orbital structures was found owing to the coupling degree of intrinsic molecular resonance and photo-induced charge transfer. A sensitive detection of lycopene in beverage samples with a high recovery rate was finally realized by the BP/ZIF-67 composite substrate, which exhibited great potential in practical molecular selective recognition. [ABSTRACT FROM AUTHOR]

[Display omitted] • A RuSe 2 /MoSe 2 heterostructure was prepared for HER in alkaline media. • RuSe 2 nanoparticles was uniformly dispersed onto MoSe 2 rods. • The charge redistribution over interface of RuSe 2 /MoSe 2 facilitated charge transfer. • The RuSe 2 /MoSe 2 heterostructure exhibited good performance for HER in alkaline media. • DFT was performed to investigate the mechanism behind performance improvement. Despite being regarded as a favorable substitute for platinum-based catalysts in hydrogen evolution reaction (HER), molybdenum diselenide (MoSe 2) exhibits inferior electrocatalytic performance due to its inadequate conductivity and limited active sites. However, employing molecular engineering for modification holds great potential in significantly enhancing its performance, yet it still poses significant challenges. Herein, an interface engineering strategy was adopted to obtain RuSe 2 modified MoSe 2 composite catalysts (RuSe 2 /MoSe 2). In alkaline media, RuSe 2 /MoSe 2 exhibited a reduced overpotential of 147.8 mV at 10 mA cm−2 comparing with pristine MoSe 2 (351.8 mV). Experimental findings and density functional theory (DFT) calculations indicated that increased conductivity, enhanced hydrophily and optimized adsorption free energies of hydrogen contribute to its enhanced HER activity. This work opens up an interface engineering strategy for designing more efficient selenide-based electrocatalysts. [ABSTRACT FROM AUTHOR]