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[Display omitted] • A simple and highly specific ratiometric fluorescence probe for AMP was firstly developed based on Eu-MOF and carbon dots. • The sensing platform could discriminate AMP from ADP and ATP through fluorescence restortion. • The probe exhibits a broad linear range of 1.0–80.0 μmol/L with LOD of 0.25 μmol/L. The selective detection of adenosine monophosphate (AMP) is of great significance for the study of cellular energy metabolism. In this study, a ratiometric fluorescent probe was designed based on europium-based metal–organic frameworks (Eu-MOF) and nitrogen-doped carbon dots (CDs) that could specifically recognize AMP. Europium nitrate and Disodium Terephthalate (Na 2 BDC) were used to synthesize Eu-BDC with red fluorescence. The fluorescence of the Eu-BDC was effectively suppressed due to water molecules coordinating with the Eu3+. However, the addition of AMP resulted in a significant restoration of the fluorescence of Eu-BDC, while the fluorescence remained suppressed upon addition of adenosine diphosphate (ADP) and adenosine triphosphate (ATP). We developed a ratiometric fluorescence sensor that could accurately detect AMP by utilizing the blue fluorescence emitted from CDs as a reliable reference signal. Under optimal conditions, the Eu-BDC/CDs system for AMP detection exhibited a linear detection range of 1.0–80.0 μmol/L and a low limit of detection (LOD) of 0.25 μmol/L. The method displayed simple preparation, high selectivity and low cost for AMP detection. To our knowledge, this is the first highly-specify double-response biosensor for AMP. [ABSTRACT FROM AUTHOR]

Pure hexagonal β -NaYF4 micron crystals were synthesized by the hydrothermal method with the up-conversion luminescence properties studied by doping Yb 3 + /Ho 3 + . The up-conversion fluorescence spectra and fluorescence lifetime of β -NaYF4 micron crystals were determined by FLS-980 transient fluorescence spectrometer. By changing the doping concentration of Yb 3 + /Ho 3 + , the optimal doping concentration was confirmed to be 20%Yb 3 + /2%Ho 3 + . The fluorescence spectrum was obtained by changing pump power, the relationship between power and intensity was analyzed, and the β -NaYF4 micron crystal green and red emission up-conversion process was obtained into a two-photon process. The 5F 4 → 5 I8 and 5S 2 → 5 I8 of the sample were thermally coupled to obtain a large absolute sensitivity (Sa) of low temperature. The maximum absolute sensitivity within the range of 64–194 K is 0.0097 K − 1 at 144 K, while maximum absolute sensitivity at 333 K is 0.00335 K − 1 in the range of 293–493 K. The experimental results show that the sensing characteristics of β -NaYF4:Yb 3 + /Ho 3 + at low temperature are better than those at high temperature, and it has the potential to be used in the field of temperature sensing. [ABSTRACT FROM AUTHOR]

• New peroxidase-like nanomaterials were prepared by using PDA as both carbon and nitrogen sources. • The specificity of N-doped C-PDANTs was improved by high N doping. • The mechanism for the intrinsic peroxidase-like activity of N-doped C-PDANTs was deciphered by electrochemical studies. • The application of N-doped C-PDANTs were demonstrated in the detection of glutathione. The introduction of nitrogen heteroatoms into enzyme-like carbon materials is an effective strategy to enhance both catalytic activity and specificity. Herein, we described the preparation of the carbonized polydopamine nanotubes (C-DPANTs) using sacrificial halloysite nanotubes (HNTs) templates. The resulting nitrogen doped C-PDANTs (N-doped C-PDANTs) exhibit solely the peroxidase-like activity owing to the high N doping. N-doped C-PDANTs could catalyze the reduction of H 2 O 2 to produce OH● radicals, which contributed to the oxidation of 3,3', 5,5'-tetramethylbenzidine (TMB) substrates. Moreover, the catalytic mechanism of N-doped C-PDANTs was further revealed by electrochemical measurements. N-doped C-PDANTs with pyridinic N and graphitic N compositions possess the capability to accelerate the electron transfer, thus facilitating the reduction of H 2 O 2. The application of N-doped C-PDANTs were demonstrated in the sensitive detection of glutathione (GSH) in serum samples. Therefore, the present study provides a facile way to prepared peroxidase-like nanomaterials with high specificity. [ABSTRACT FROM AUTHOR]

Developing metal-free carbon electrocatalysts with atomically precise structures of hetero-doping is crucial for inventing reliable alternatives to precious metal-based catalysts. Our study reveals that the optimal active site is the edge-exposed N-neighbored carbon site in a chained N- C -C-S structure. Carbon material with N- C -C-S functional doping is controllably synthesized through polymer dehalogenation and heteroatom doping with thiomorpholine at room temperature. The resulting N/S-co-doped carbon with N- C -C-S functionalization, named N-C 2 -S, exhibits excellent ORR performance compared to other types of N, S-co-doped carbon, and commercial Pt/C. Typically, the N-C 2 -S sample shows the earliest onset potential of 0.96 V and a high half-wave potential of 0.85 V for promoting ORR. Assembled into an Al-air battery, The N-C 2 -S delivers an exceptional open-circuit voltage of 1.95 V and a large specific power of 128.1 mW cm 2. The synthesis strategy developed in this work can potentially open up precise functionalization of synthetic carbons with heteroatoms. [Display omitted] • The C site near the N in N-C-C-S is identified as highly active for oxygen reduction. • Different types of N, S-co-doped carbon are obtained via dehalogenation of PVDC. • N-C-C-S doping is realized via dehalogenation coupling reaction with thiomorpholine. • The N-C 2 -S sample exhibits exceptionally good oxygen reduction reaction performance. • The N-C 2 -S-assembled Al-air battery delivers high cell voltages and large powers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 3 BTC 2 MOF-impregnated boron-doped biochar was successfully fabricated by a one-pot strategy. • HKUST-1/BBC delivered superior NH 3 sorption capability at 10.44 mmol∙g−1 at 298 K and 100 kPa. • HKUST-1/BBC exhibited a fast NH 3 sorption process and in line with PSO kinetics model. • The adsorption mechanism of NH 3 on HKUST-1/BBC was ascribed to a reactive adsorption process. Ammonia (NH 3) is a typical malodorous pollutant and one of the key factors causing PM2.5. This study proposed a one-pot impregnating method to synthesize a novel NH 3 sorbent-boron (B)-doped biochar derived from waste orange peels impregnated with Cu 3 BTC 2 MOFs (i.e., HKUST-1/BBC). Boric acid activation, boron-doping, and HKUST-1 impregnation provided a structure with more pores and sorption sites on the surface of the HKUST-1/BBC composite. The as-fabricated HKUST-1/BBC-5-2.5 (5 representing the mass ratios of added H 3 BO 4 to orange peels powder, 2.5 indicating the mass ratio of B-doped porous biochar BBC-5 to pure HKUST-1) had a 3.71 at.% nitrogen and 1.96 at.% boron content, as well as the largest specific surface area of 674.31 m2·g−1, delivering an outstanding NH 3 capture capacity of 10.44 mmol·g−1 at 298 K and 100 kPa, and a fast sorption kinetics (circa 95 % of balance capacity after 15 min), and moderate heat of sorption (25 to 50 kJ·mol−1). The sorption mechanism of NH 3 on HKUST-1/BBC-5-2.5 was proposed to be a reactive adsorption process. This study demonstrates the HKUST-1/BBC-5-2.5 as a sorbent for enhanced NH 3 capture, as well as offers a facile and scalable production strategy for processing waste peels as adsorbent to absorb waste gas. [ABSTRACT FROM AUTHOR]

We always pursue improved energetic performances such as high formation enthalpies, moderate sensitivities and stabilities for all energetic compounds. 1,3,5‐trinitroperhydro‐1,3,5‐triazine (RDX) is a very classic high‐energy explosive which has been applied in both military and civilian fields broadly, whose combustion properties can be enhanced by introducing hydrogen‐storage compounds such as Lithium amidoborane (LAB). Here we apply CPMD method to study how LAB affects a traditional nitramine explosive (RDX) in a simulated detonation. The theoretical results show there are abundant exothermic reactions caused by the introduction of LAB, which suggests hydrogen‐storage material is a prospective assistant ingredient for composite explosives. We apply CPMD method to study how LAB affects a traditional nitramine explosive (RDX) in a simulated detonation. Here we have observed 176 species and more than 200 elementary reactions in one unit cell. The main products are CO2, N2, NH3, H2O, N2O and NO. Compared with the decomposition of pure RDX, the entropy and the corresponding released energy are significantly improved for LAB‐RDX. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Cu/NBC was fabricated by modifying N-doped biochar with Cu MOF-derived Cu. • Cu/NBC exhibited superior desulfurization capacity of 158.28 mg/g at low temperature. • The main desulfurization products of H 2 S were composed of sulfur and copper sulfide. • Desulfurization mechanism involved synergistic catalytic oxidation and adsorption. Hydrogen sulfide (H 2 S) is a highly toxic and corrosive gas that poses significant risks to human health and the environment. Therefore, the development of an adsorbent capable of efficiently purifying H 2 S at room temperature remains a challenging task. In this study, a novel composite adsorbent with a specific surface area of 434 m2·g−1 was fabricated by modifying porous N-doped biochar with Cu nanoparticles (Cu/NBC) derived from Cu-MOFs for low-temperature desulfurization of H 2 S. The effect of pyrolysis temperature and the doping ratio of Cu-MOFs to biochar on the desulfurization performance of H 2 S for the as-prepared Cu/NBC was comprehensively investigated. Experimental results indicated that the desulfurization capability of the optimized Cu/NBC-600-1 adsorbent (synthesized at a pyrolysis temperature of 600 °C and a doping ratio of 1:1) was significantly affected by the desulfurization conditions, and the optimal conditions were determined to be at 25 °C, with 20 % oxygen content and 70 % relative humidity. Under the optimized conditions, the Cu/NBC-600-1 adsorbent exhibited a high H 2 S removal capacity of 158.28 mg·g−1, which was about 3.8 times higher than that of the pristine N-doped biochar. The desulfurization mechanism of the Cu/NBC composite was demonstrated to involve reactive adsorption and catalytic oxidation, resulting in the formation of elemental sulfur and copper sulfides as the main products. This study not only provides a promising approach to modify porous biochar with MOF derivatives, but also offers an effective strategy to remove low concentration H 2 S at room temperature. [ABSTRACT FROM AUTHOR]

The remote and non-invasive optical thermometer exploiting fluorescence intensity ratio technology is of great importance in various intelligent optoelectronic sensors. Dual-emitting YNbO 4 :Bi3+, Eu3+ phosphor is synthesized and investigated for the development of temperature sensing materials. The phosphor excited at 318 nm shows a blue broad band emission and several red sharp peaks. The value of Bi3+→Eu3+ energy transfer can reach 98.2% when Eu3+ doping content is 0.14. Benefiting from diverse thermal response behaviors due to Bi3+ and Eu3+ ions completely different electronic configurations, a dual-emitting optical thermometer is designed. The maximum values of absolute and relative sensitivities are as high as 2.51% K−1 at 473 K and 1.43% K−1 at 423 K, respectively. The thermochromic phosphor possesses a great chromaticity shift (ΔE = 317×10−3) with temperature. Based on superior color discriminability, visual colorimetry temperature measurement relied on thermal characteristic is proposed. All the results demonstrate that YNbO 4 :0.01Bi3+, 0.005Eu3+ phosphor as a sensitive and reliable optical thermometer has great potentials in temperature measurement. [ABSTRACT FROM AUTHOR]

[Display omitted] • A MgFe 2 O 4 -loaded and N -doped biochar (MgFe 2 O 4 @NBC) was fabricated by one-pot pyrolysis method. • MgFe 2 O 4 @NBC realized synergistic desulfurization of H 2 S by metal oxide loading and N doping. • MgFe 2 O 4 @NBC delivered superior desulfurization capacity of 1052.83 mg/g at room temperature. • The desulfurization mechanism of H 2 S on MgFe 2 O 4 @NBC was verified by in-situ DRIFTS and XPS. • The desulfurization process of H 2 S was a combination of catalytic oxidation and reactive adsorption. To improve their low-temperature desulfurization performance, the activated carbon-based materials have typically been modified by either metal oxide loading or nitrogen doping. However, most of the aforementioned materials are limited to only one of the above modification methods, resulting in relatively poor desulfurization performance. Herein, a novel MgFe 2 O 4 -loaded N -doped biochar (MgFe 2 O 4 @NBC) was fabricated by one-pot pyrolysis of a nitrogen containing precursor of g-C 3 N 4 , cooked rice waste, and metal salts for efficient low-temperature desulfurization of H 2 S. Different fabrication conditions such as pyrolysis temperature and the nitrogen mixing ratio (i.e., the mass ratio of cooked rice waste to g-C 3 N 4) have been extensively studied. The optimized MgFe 2 O 4 @NBC-500–2 sample delivered a superior breakthrough capacity of 1052.83 mg/g in an atmosphere of O 2 content of 20% and relative humidity of 80% at 25 °C, and demonstrated high tolerance and stability of desulfurization performance to harsh environmental conditions with 80% relative humidity and no oxygen. The desulfurization mechanism of H 2 S on the surfaces of the MgFe 2 O 4 @NBC composites was attributed to the synergistic effects of reactive adsorption and catalytic oxidation process. The composite also demonstrated excellent reusability, retaining 85% of the initial breakthrough capacity after 5 recycled uses. Therefore, the as-prepared MgFe 2 O 4 @NBC composite offers a potentially promising carbon-based desulfurizers for practical applications in the low-temperature desulfurization field. [ABSTRACT FROM AUTHOR]

Single phase multiferroics are rare in nature, because ferroelectric and ferromagnetic orderings require empty d -orbits and filled d -orbits, respectively. Here we demonstrate that ferroelectricity can be induced by ion-pair doping in ferromagnetic oxide such as ferrites with filled d -orbits. Our study shows that a new kind of room temperature multiferroic can be achieved in single phase thin films of CoFe 2 O 4 with Li + -Al 3+ pair substitution of Co 2+ along 〈110〉 direction. A ferroelectric domain mechanism related to ion-pairs in co-doped thin films was revealed. Importantly, a new way for fabricating single phase multiferroic materials is provided in the present study. [ABSTRACT FROM AUTHOR]

[Display omitted] • B-TiO 2 /LDH heterojunction was successfully fabricated via in-situ hydrothermal synthesis. • B-TiO 2 /LDH delivered a superior 100% H 2 S removal efficiency by visible-light-driven photocatalysis. • B-TiO 2 /LDH exhibited high photocatalytic performance of H 2 S under different desulfurization conditions. • B-TiO 2 /LDH was demonstrated remarkable stability in a long-term desulfurization test. • The sulfate formed on B-TiO 2 /LDH was proven to boost H 2 S catalytic oxidation process. Hydrogen sulfide (H 2 S), a highly toxic, malodorous, and corrosive gas, poses a serious threat to the atmospheric environment and human health. It is highly attractive to design high-performance desulfurization photocatalyst in environmental remediation. Herein, a novel and highly efficient photocatalyst boron-doped TiO 2 combined with MgAl-Layered double hydroxides (B-TiO 2 /LDH) was synthesized via an in-situ hydrothermal method. The B-TiO 2 /LDH photocatalyst exhibited outstanding photocatalytic performance with 100% H 2 S removal efficiency within 120 min under visible light irradiation. The B-TiO 2 /LDH photocatalyst also exhibits a good H 2 S removal efficiency in different desulfurization conditions and delivers remarkable stability in a long-term test. The sulfate formed on the surface of B-TiO 2 /LDH has been shown to favor the light-enhanced catalytic oxidation process. This work provides a promising idea for effectively treating malodorous gas and shows potential of using the novel B-TiO 2 /LDH photocatalyst for future environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Micro-swelling and penetration assisted laser processing (MSPALP) method introduces benzophenone into polydimethylsiloxane films by swelling and penetration behavior to adjust properties of films and improve its laser processing. • MSPALP method performs higher efficiency, less thermal effects and better quality and eliminates the impacts of dopant on polydimethylsiloxane films. • The kerf with a high aspect ratio and quality can be obtained by controlling the benzophenone content. • The interactions between laser, dopant and polydimethylsiloxane promote the photochemical decomposition of polydimethylsiloxane and suppress photothermal reactions. Polydimethylsiloxane and its laser processing have significance in broad fields. The problems caused by poor absorption and current doping methods have prevailed in the laser processing of polydimethylsiloxane. Here, a simple and efficient dopant-induced laser processing method based on the swelling and penetration behavior was presented to improve the laser processing of polydimethylsiloxane films: micro-swelling and penetration assisted laser processing. In this method, the dopant benzophenone was introduced into polydimethylsiloxane films through micro-swelling and penetration pretreatment to adjust its physical/chemical properties so as to improve the laser processing. Results showed that micro-swelling and penetration assisted laser processing method performed higher efficiency, capability (Depth: 625.9 ± 38 μm, Width: 13.2 ± 0.9 μm, Aspect Ratio: 47.4 ± 1.7:1) and quality (no debris or micro-crack and less thermal effects) compared to the typical laser processing method (Depth: 140.1 ± 5.7 μm, Width: 28.0 ± 2.0 μm, Aspect Ratio: 5.0 ± 0.4:1). The introduction of benzophenone changed the polydimethylsiloxane films' optical, photochemical and thermodynamic properties and affected its laser ablation process, in which the more complete and uniform photochemical decomposition of polydimethylsiloxane films was promoted due to that benzophenone molecules absorbed photon energy and decomposed, and transferred energy to polydimethylsiloxane. Moreover, this method hardly influenced the original properties of polymer films due to the removability of dopants. [ABSTRACT FROM AUTHOR]