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Gas sensors based on noble metal/metal oxide are applied extensively, and show a relatively high response to carbon monoxide at inferior operating temperature. In this paper, a carbon monoxide sensor based on Pt decorated SnO2 nanoparticles is obtained by a hydrothermal method. Abundant characterization methods are used to analyze the structure, morphology, chemical state and specific surface area of the as-prepared compounds. The pure SnO2 sensor exhibits inferior operating temperature and low response for the detection of carbon monoxide. In contrast, the observed response of the sensor with the as-synthesized 1.5 mol% Pt decorated SnO2 is up to 610.45 at a low operating temperature of 80 °C, and the response value is about three times higher than that of SnO2 sensor. The significantly improved performance is thoroughly explained in terms of the adsorption-desorption mechanism, and the chemical sensitization and electronic sensitization of Pt. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a Ni(OH)2@Ni foam binder‐free electrode was obtained through the corrosion of Ni foam with ultrapure water under hydrothermal conditions. The structure, morphology, and surface chemical states of the obtained Ni(OH)2@Ni foam were characterized by X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy. The chemical formation mechanism is discussed. In addition, it was found that the loading amount and morphology of the deposited Ni(OH)2 depend largely on the corrosion time. Furthermore, electrodes corroded for different times were then directly used as working electrodes to investigate the areal and specific capacitances of the deposited Ni(OH)2 by using cyclic voltammetry, through which a relationship between the corrosion time, loading amount, morphology, and final capacitance is built up. The electrode with the highest areal capacitance was further studied with cyclic voltammetry, galvanostatic charge−discharge processes, as well as electrochemical impedance spectroscopy. The as‐prepared Ni(OH)2@Ni foam is a typical pseudocapacitance electrode. At a high current density of 5 mA cm−2, the electrode exhibits an areal capacitance of 0.863 F cm−2. For the deposited Ni(OH)2, its specific capacitance reaches 693 F g−1 at a current density of 4 A g−1. After 3000 charge−discharge cycles at a current density as high as 10 A g−1 (12.5 mA cm−2), the areal capacitance retains 77.3 % of its initial value. The findings in this work could be meaningful for the corrosion preparation of related electrodes and the design of binder‐free electrodes. [ABSTRACT FROM AUTHOR]

Light‐emitting diode (LED)‐driven displays create colored images by down‐converting an intense blue LED signal to longer wavelengths using inorganic phosphors. Unfortunately, overexposure to this blue LED emission throughout the course of a day has been linked to insomnia and mood disorders. “Human‐centric” lighting can alleviate this problem by transitioning to safe violet LED driven devices and utilizing a trichromatic phosphor mixture. For further details see article number 2202689 by Jakoah Brgoch and co‐workers. [ABSTRACT FROM AUTHOR]

Anatase–rutile mixed-phase TiO2 is proved to have better photocatalytic activity than pure anatase TiO2, but the preparation of the mixed-phase TiO2 usually needs thermal treatments at more than 500 °C. In this study, we present a one-step nonaqueous sol–gel route to form mixed-phase TiO2 at relatively low temperatures from 160 to 220 °C. The structure, morphology and surface chemical state were examined with X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), respectively. The influence of the preparation temperature on the structural characteristics including grain size and phase content were investigated using the Rietveld refinement. Through TEM, the evolution from sphere-like anatase nanoparticle to hexagonal rutile single-crystal was investigated. The photocatalytic activities of the obtained anatase and anatase-rutile TiO2 were evaluated by degradation of Rhodamine B under visible light, and a distinct enhanced activity was observed. Through the UV-vis spectrum and mass spectrum, the pathway of RhB degradation caused by the mixed-phase TiO2 with visible light was studied. At the same time, the mechanism of the enhanced photocatalytic properties was presented. The mechanisms were verified with UV-vis measurements. It is believed that the obtained mixed-phase TiO2 is one promising candidate for wastewater treatment. [ABSTRACT FROM AUTHOR]

• The high-temperature gasification and melting properties of PRPS were studied. • The PRPS prepared at 650 °C shows the best gasification reactivity. • The high-yield effective gas (CO + H 2) was found in the N 2 /CO 2 atmosphere. • The high-density of slag and reduction of PRPS was obtained in the N 2 /CO 2 atmosphere. High-temperature gasification and melting is a promising technology for the harmless disposal and resource utilization of hazardous organic solid wastes. In this study, the high-temperature gasification and melting properties of pyrolysis residues from petrochemical sludge (PRPS) were experimentally investigated. Firstly, the PRPSs in pyrolysis temperatures of 500–700 °C were prepared. The gasification reactivity of PRPSs was investigated through micropolitics pore structure and Raman spectrum analysis. The results show that the PRPS prepared at 650 °C has the best gasification reactivity, with both large surface area and more complete porous structure, and more disordered carbon microstructures. Then, based on the PRPS sample prepared at 650 °C, the effects of the gasification temperature (1100–1400 °C) and atmosphere (N 2 , H 2 O, and CO 2) were studied. In the atmosphere of 40 vol.%N 2 /30 vol.%CO 2 /30 vol.%H 2 O, the yield of effective gas (CO+H 2) began to decrease when the temperature was above 1200 °C. With the increase of temperature (1300–1400 °C), high-density slag of PRPS was observed. At the temperature of 1400 °C, the highest yield of effective gas (CO+H 2), the high-density slag, and the reduction of PRPS were obtained in the atmosphere of 40 vol.%N 2 /60 vol.%CO 2. In this condition, the high CO is conducive to form FeO as fluxing. Moreover, the stable mineral phases (CaSiO 3 , CaSi 2 O 7 , etc.) were detected, which should perform a good solidification effect of heavy metals in the slag. [ABSTRACT FROM AUTHOR]

Although both protein arginine methylation (PRMT) and jasmonate (JA) signaling are crucial for regulating plant development, the relationship between these processes in the control of spikelet development remains unclear. In this study, we used the CRISPR/Cas9 technology to generate two OsPRMT6a loss-of-function mutants that exhibit various abnormal spikelet structures. Interestingly, we found that OsPRMT6a can methylate arginine residues in JA signal repressors OsJAZ1 and OsJAZ7. We showed that arginine methylation of OsJAZ1 enhances the binding affinity of OsJAZ1 with the JA receptors OsCOI1a and OsCOI1b in the presence of JAs, thereby promoting the ubiquitination of OsJAZ1 by the SCFOsCOI1a/OsCOI1b complex and degradation via the 26S proteasome. This process ultimately releases OsMYC2, a core transcriptional regulator in the JA signaling pathway, to activate or repress JA-responsive genes, thereby maintaining normal plant (spikelet) development. However, in the osprmt6a-1 mutant, reduced arginine methylation of OsJAZ1 impaires the interaction between OsJAZ1 and OsCOI1a/OsCOI1b in the presence of JAs. As a result, OsJAZ1 proteins become more stable, repressing JA responses, thus causing the formation of abnormal spikelet structures. Moreover, we discovered that JA signaling reduces the OsPRMT6a mRNA level in an OsMYC2-dependent manner, thereby establishing a negative feedback loop to balance JA signaling. We further found that OsPRMT6a-mediated arginine methylation of OsJAZ1 likely serves as a switch to tune JA signaling to maintain normal spikelet development under harsh environmental conditions such as high temperatures. Collectively, our study establishes a direct molecular link between arginine methylation and JA signaling in rice. This study shows that arginine methylation of OsJAZ1 by OsPRMT6a enhances its binding affinity with OsCOI1a/OsCOI1b, thus promoting the ubiquitination and degradation of OsJAZ1 and, ultimately, jasmonate (JA) responses. In the osprmt6a-1 mutant, the absence of OsJAZ1 arginine methylation results in stabilization of OsJAZ1 proteins, thus repressing JA responses and ultimately leading to abnormal spikelet structures. In addition, JA signaling reduces the OsPRMT6a mRNA level, establishing a negative feedback loop to balance JA signaling. [ABSTRACT FROM AUTHOR]

Ultra-long life fatigue tests of 106-109 cycles under asymmetrical loading were conducted to elucidate the subsurface facets-induced crack nucleation behavior of two alpha-beta titanium alloys, and a theoretical method of describing the microstructure-based strength relationship was proposed. As a result, two titanium alloys all present the continuously descending S – N (stress - number of cycles) curve characteristics with subsurface non-defect induced failure. A bright convergence zone with facets becomes the remarkable feature of failure. By means of the milling of focused ion beam system, the coalescence and growth of subsurface micro-cracks crossing several grains along the 45° angle, controlled by the maximum shear stress, can be observable. Based on this, a subsurface facets-induced crack nucleation and growth mechanisms for titanium alloys was proposed in combination with the discussion of small crack fracture mechanics. In view of the good consistency between the evaluated nucleation life of crack at the size of convergence zone with facets and the total life, the microstructure-based modelling method for evaluating fatigue strength of titanium alloys with subsurface failure in ultra-long life regime can be acceptable. [ABSTRACT FROM AUTHOR]

Citric acid capped CdS quantum dots (CA-CdS QDs), a new assembled fluorescent probe for copper ions (Cu2+), was synthesized successfully by a simple hydrothermal method. In this work, the fluorescence sensor for the detection of heavy and transition metal (HTM) ions has been extensively studied in aqueous solution. The results of the present study indicate that the obtained CA-CdS QDs could detect Cu2+ with high sensitivity and selectivity. It found that the existence of Cu2+ has a significant fluorescence quenching with a large red shifted (from greenish-yellow to yellowish-orange), but not in the presence of 17 other HTM ions. As a result, Cu2S, the energy level below the CdS conduction band, could be formed at the surface of the CA-CdS QDs and leads to the quenching of fluorescence of CA-CdS QDs. Under optimal conditions, the copper ions detection range using the synthesized fluorescence sensor was 1.0 × 10‒8 M to 5.0 × 10‒5 M and the limit of detection (LOD) is 9.2 × 10‒9 M. Besides, the as-synthesized CA-CdS QDs sensor exhibited good selectivity toward Cu2+ relative to other common metal ions. Thus, the CA-CdS QDs has potential applications for detecting Cu2+ in real water samples. [ABSTRACT FROM AUTHOR]

Pd-functionalized one-dimensional (1D) SnO2 nanostructures were synthesized via a facile hydrothermal method and shaddock peels were used as bio-templates to induce a 1D-fiber-like morphology into the gas sensing materials. The gas-sensing performances of sensors based on different ratios of Pd-functionalized SnO2 composites were measured. All results indicate that the sensor based on 5 mol % Pd-functionalized SnO2 composites exhibited significantly enhanced gas-sensing performances toward butane. With regard to pure SnO2, enhanced levels of gas response and selectivity were observed. With 5 mol % Pd-functionalized SnO2 composites, detection limits as low as 10 ppm with responses of 1.38 ± 0.26 were attained. Additionally, the sensor exhibited rapid response/recovery times (3.20/6.28 s) at 3000 ppm butane, good repeatability and long-term stability, demonstrating their potential in practical applications. The excellent gas-sensing performances are attributed to the unique one-dimensional morphology and the large internal surface area of sensing materials afforded using bio-templates, which provide more active sites for the reaction between butane molecules and adsorbed oxygen ions. The catalysis and "spillover effect" of Pd nanoparticles also play an important role in the sensing of butane gas as further discussed in the paper. [ABSTRACT FROM AUTHOR]

The g-C3N4-coupling TiO2 photocatalysts with controllable particle size as well as the interface contact were prepared by a general nonaqueous sol-gel method. The structural and morphological features of g-C3N4/TiO2 were investigated through the X-ray diffraction, Fourier transformed infrared spectra, scanning electron microscopy and transmission electron microscopy, respectively. It is found the TiO2 nanoparticles with a size of 7.3 ± 1.6 nm are uniformly anchored on the surface of the g-C3N4 nanosheets in isolation. The photocatalytic properties of as-prepared g-C3N4/TiO2 were tested by degradation of Rhodamine B (RhB) under visible light, and an enhanced activity is observed. The mechanism of the enhanced activity was further investigated through N2 adsorption-desorption isotherms, UV-vis spectra, photoluminescence spectra, photoelectrochemical measurements, radical trapping experiments and X-ray photoelectron spectroscopy. Furthermore, the photocatalytic performances of obtained g-C3N4/TiO2 under sunlight were also evaluated in aspects of degradation efficiency and stability. The results indicate that the obtained g-C3N4/TiO2 is one promising photocatalyst for practical applications. The study of as-prepared g-C3N4/TiO2 also implies that the present method could be a general route of g-C3N4-coupling photocatalysts. [ABSTRACT FROM AUTHOR]

Abstract Water-soluble rhodamine B assisted graphene quantum dots (RhB-GQDs) were synthesized by a facile one-pot hydrothermal method, using rhodamine B and ethylenediamine as nitrogen source. The as-synthesized RhB-GQDs have few layers configuration with an average size of 4.5 nm and good distribution. The fluorescence quenching approach was applied to the sensing of mercury ions in water. Rodamine B absorb on the surface of RhB-GQDs, and it can prevent RhB-GQDs from contacting with interfering cations. The presence of N atoms reduces the ability of interfering cations to form stable complex with carboxyl groups, and gives the RhB-GQDs good selectivity to mercury ions. In the case of low concentration, the fluorescence quenching efficiency of as-synthesized RhB-GQDs still has a good liner relationship with concentration. Due to the strong affinity of Hg2+ to amino and carboxyl on the surface of RhB-GQDs, the fluorescence of RhB-GQDs is quenched by nonradiative electron transfer between Hg2+ and the excited state of RhB-GQDs. Based on the fluorescence turn off process, the as-synthesized RhB-GQDs can be served as fluorescent platform for the sensitive and selective detection of Hg2+ with a detection limit of 0.16 nM. Graphical abstract Rhodamine B assisted graphene quantum dots (RhB-GQDs) synthesized a facile one-pot hydrothermal method using rhodamine B and ethylenediamine as nitrogen source exhibit the excellently selective and sensitive response to Hg2+ as flourescent sensor. fx1 [ABSTRACT FROM AUTHOR]

To understand the potential effects of intrinsic calcium compounds on sludge pyrolysis, the pyrolysis behavior of petrochemical sludge (PS), calcium carbonate blend PS (CaPS), and decalcified PS (DePS) were investigated using thermogravimetric analysis (TGA) and in-situ Fourier-transform infrared spectroscopy coupled with pyrolysis-gas chromatography and mass spectrometry (Py–GC/MS). The TGA results indicated that decalcification increased and decreased the energy barriers of PS decomposition in ranges 200–350 °C and 350–600 °C, respectively. In contrast, copyrolysis with CaCO 3 decreased the activation energy (E) of the pseudoreaction phase 2 (PH2) and altered the mechanism model. Meanwhile, during copyrolysis, char deposition and interaction hindered CaCO 3 decomposition. The two-dimensional correlation spectroscopy results, on the other hand, showed that the reaction priority of O-containing groups and CH– vibration of methyl groups were affected by both decalcification and CaCO 3 copyrolysis. The Py–GC/MS results indicated that the three sludges mainly released hydrocarbons, N-containing organics, alcohols, aldehydes, and acids. During pyrolysis, CaCO 3 also played a neutralization role, which reduced the release of pyrolytic acidic products. In addition, the increase of the pyrolysis temperature increased the hydrocarbon content. This research will guide the industrial application of sludge pyrolysis. [Display omitted] • Roles of intrinsic Ca compound on pyrolysis of petrochemical sludge were studied. • Decalcification increased decomposition energy barrier at low-temperature pyrolysis. • Decalcification and co-pyrolysis with CaCO 3 altered the order of char devolatilization. • Co-pyrolysis with CaCO 3 affected O-containing and methyl groups evolution. • Co-pyrolysis with DePS increased E of CaCO 3 decomposition stage by 78.4 kJ/mol. [ABSTRACT FROM AUTHOR]

SnO 2 is a typical metal oxide semiconductor gas sensitive material, which has been studied deeply. However, pure SnO 2 sensing materials usually have good performance at high operating temperatures. In this study, we reported an n-butanol sensor with high selectivity and fast response based on SnO 2 submicron porous cube prepared by heating and decomposing the Sn-based metal-organic framework material (Sn-MOF) in air at a certain temperature. SnO 2 submicron porous cube prepared at 450 °C shows good response and selectivity for n-butanol. And it has a response (%) of 175% to 100 ppm n-butanol and a relatively fast response/recovery time of 184 s/183 s at room temperature. The (110) crystal plane with sufficient oxygen-rich vacancy can adsorb O 2 and n-butanol molecules more effectively. Therefore, its sensitivity to n-butanol gas can be significantly improved. This work provides a good idea for further research on pure metal oxide semiconductor room temperature gas sensors. [ABSTRACT FROM AUTHOR]

• Electrostatic anchoring in situ polymerization synthesizes hybrid electrode materials. • MXene collaboratively with high Th loading enhances specific capacity and cycle stability. • Combining supercapacitors with perovskite solar cells achieves rapid charge storage. Portable photorechargeable supercapacitors hold great promise as ideal power sources for future IoT applications. However, the widespread implementation of supercapacitors is hindered by their suboptimal energy density. Organic electrodes, with their high specific capacity, have become rising stars in the energy storage community. Herein, we pioneer an electrostatic-anchoring in situ polymerization reaction pathway to synthesize MXene-organic hybrid electrode materials. Theoretical calculations show that thionine (Th) is the optimal candidate for grafting onto the pseudocapacitive 2D MXene due to its low energy levels, narrow band gap, and multiple active sites. Multilevel interactions between Th and MXene are established to prevent Th from dissolution, to inhibit the MXene from restacking, and to facilitate electron accumulation in Th, thus enhancing the accessibility/absorption of ions in electrolytes and electrode stability. The hybrid electrodes exhibit a specific capacity as high as 4906.7 mF/cm2 at 1 mA cm−2; more importantly, an integrated asymmetric flexible supercapacitor displays high specific capacity (3183.1 mF/cm2) and large energy density (1432.4 mWh/cm2), all three values are the highest among their respective categories. Combining supercapacitors with all-inorganic perovskite solar cells to achieve rapid charge storage. [ABSTRACT FROM AUTHOR]

Abstract Co(OH) 2 @FeCo 2 O 4 nanocomposite was successfully synthesized via a facile one-step hydrothermal reaction without thermal treatment. The structure and chemical composition of as-synthesized Co(OH) 2 @FeCo 2 O 4 was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), respectively. The results show the FeCo 2 O 4 nanosheets are covered with the Co(OH) 2 nanoparticles and the BET show the nanocomposite possess the mesoporous structure with specific surface area and total pore volume are 93.071 m2 g−1 and 0.37 cm3 g−1, respectively. In addition, the electrochemical performances were investigated in a three-electrode system to evaluate the material. The as-synthesized Co(OH) 2 @FeCo 2 O 4 nanocomposite exhibits a high specific capacitance of 1173.43 F g−1 at 1 A g−1 and remarkable cycling stability with 95.4% capacitance retention after 5000 cycles. The results show the higher capacitance and longer cycle performance, compared with the Co(OH) 2 and FeCo 2 O 4 , respectively. This remarkable electrochemical performances were mainly due to mesoporous structure and the synergistic effect of Co(OH) 2 and FeCo 2 O 4. It means that this nanostructure Co(OH) 2 @FeCo 2 O 4 synthesized by this simple and cost-effective method would have more hopeful prospects in energy storage applications. Graphical abstract Co(OH) 2 @FeCo 2 O 4 nanocomposite applied as electrode of supercapacitor shows an impressive enhancement of the performance including the areal capacitance and cycling stability. Image 1 [ABSTRACT FROM AUTHOR]

Highlights • The rougher morphology of FGA reveals the rather distorted crack growth path. • A fatigue strength evaluation model is developed. • The predicted crack growth rate reflects the discontinuous crack growth behavior. • An assessment method is proposed for predicting allowable fatigue strength. Abstract A fatigue assessment approach for interior inclusion-FGA (fine granular area)-fisheye induced fracture was proposed through experimental investigation of very high cycle fatigue properties of two high-strength low-alloy steels. The rougher morphology of FGA reveals the rather distorted crack growth path and slow crack growth rate. A strength evaluation model related to defect size and fatigue life was developed, using which the predicted results are in agreement with the experimental results. Based on the modelling of micro-crack growth rate, the evaluated value can be less than the magnitude of one Burger's vector, which reflects the discontinuous crack growth behavior within FGA. [ABSTRACT FROM AUTHOR]

Nanoporous titanium dioxide was synthesized by a hydrothermal method without using of surfactant or template. The structure, morphology, surface chemical states and specific surface area were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and N 2 adsorption-desorption isotherms, respectively. The as-synthesized products are anatase-TiO 2 with small grain size (about 12.27 nm) and high surface area (147.17 m 2 g −1 ). The as-synthesized porous TiO 2 powder was used to fabricate indirect-heating gas sensor whose gas-sensing characteristics toward acetone were investigated. At its optimal operation temperature, the sensor possesses a good sensitivity, selectivity, linear dependence, low detection limitation, and response/recovery, repeatability as well as long-term stability. Especially for the high sensitivity and fast response/recovery, its response reaches 25.97 for 500 ppm acetone, which is several times higher that of the reported TiO 2 -based sensors. The response and recovery times are only 13 and 8 s, respectively. Those values demonstrate the potential of using as-synthesized TiO 2 for acetone gas detection, particularly in the dynamic monitoring. Apart from these, the mechanism related to the advanced properties was also investigated and presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell-structured CoP x @FeOOH is designed as an efficient catalyst for selective seawater oxidation. • This hierarchical catalyst has high conductivity, large surface area, and improved turnover frequency, which lead to superb OER performance. • The strong chloride corrosion resistance and enhanced chemical stability help it work well in alkaline seawater electrolyte. • The CoP x ||CoP x @FeOOH pair requires low voltages to attain high current densities for overall seawater splitting with high Faradaic efficiency and excellent stability. Hydrogen generation by seawater electrolysis is a sustainable approach to renewable-energy conversion which requires efficient catalyst to address challenges such as competing chlorine evolution reaction, chloride corrosion, and catalyst poisoning. Here, core-shell-structured CoP x @FeOOH is designed for selective OER in seawater. This catalyst has high conductivity, large surface area, improved turnover frequency, and optimal absorption energy to OER intermediates, which together lead to excellent catalytic activity. The enhanced chemical stability and corrosion resistance ensure its catalytic performance in seawater. Specifically, it requires overpotentials of 283 and 337 mV to attain current densities of 100 and 500 mA cm−2, respectively, in 1 M KOH seawater, with durability over 80 h of continuous testing without producing any hypochlorite. The CoP x ||CoP x @FeOOH pair requires voltages of 1.710 and 1.867 V to attain current densities of 100 and 500 mA cm−2 with a high Faradaic efficiency, showing its great promise for fuel-gas production from seawater. [ABSTRACT FROM AUTHOR]

• The interior microcrack growth in the maximum shear stress plane is observed in FIB milling. • Formation of facets is attributed to the pure slip where the facet plane is closed to 45°. • The crack growth rate within the IMZ is less than the magnitude of one Burger's vector. • A strength evaluation approach with facet-IMZ-fisheye induced failure is proposed. Very high cycle fatigue properties of titanium alloys under symmetrical and asymmetrical loads were experimentally examined to clarify the failure behavior. An inhomogeneous microstructure zone (IMZ) containing facets is observable. By focused ion beam testing, the interior micro-crack extends along the maximum shear stress plane and the facet plane is about 45°. By the modeling of growth rate and the definition of controlling line, a strength evaluation approach with the failure behavior was well proposed. This reflects that the micro-crack growth rate in IMZ stage is below one Burger's vector. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) structural Cd-doped SnO 2 are prepared using shaddock peels as bio-templates via a facile hydrothermal method. The as-synthesized materials are characterized by different techniques, including XRD, FESEM, TEM, XPS and N 2 adsorption-desorption. Interestingly, unique 1D fiber-like structures are observed and composed of numerous small nanoparticles. Moreover, the result shows that 5 mol% Cd-doped SnO 2 nanofibers possesses a larger specific surface area of 38.850 m2/g. At the same time, the gas-sensing properties of sensors based on as-prepared SnO 2 nanofibers are also investigated. The 5 mol% Cd-doped SnO 2 nanofibers based sensor shows the highest response towards formaldehyde at a lower operating temperature of 160 °C. The excellent gas-sensing properties of sensor towards formaldehyde may attribute to the unique 1D fiber-like structure, large specific surface area and the additive of Cd, which can provide more active sites for the reaction between adsorbed oxygen ions and formaldehyde molecules on the surface of sensing materials. In addition, based on the above experimental results, the possible sensing mechanism of sensor towards formaldehyde is discussed in detail. Gas sensor based on 5 mol% Cd-doped SnO 2 nanofibers prepared using shaddock peels as bio-templates via a facile hydrothermal method shows high gas response, low detection limit and fast response toward various formaldehyde gas at the relative low operating temperature of 160 °C. Image 1 • Cd-doped SnO 2 nanofibers were using shaddock peels as bio-templates at first time. • Cd-doped SnO 2 nanofibers based gas sensor shows a high response towards formaldehyde. • Sensor has good repeatability, stability, fast response and recovery towards formaldehyde. • 1D structure increases surface area and oxygen specie to promote oxidation of formaldehyde. [ABSTRACT FROM AUTHOR]

Understanding the effects of laser light, water vapor, and energetic electron irradiation on the intrinsic properties of perovskites is important in the development of perovskite-based solar cells. Various phase transition and degradation processes have been reported when these agents interact with perovskites separately. However, detailed studies of their synergistic effects are still missing. In this work, the synergistic effect of three factors (exposure to laser light, water vapor, and e-beam) on the optical and physical properties of two-dimensional (2D) Ruddlesden-Popper (RP) perovskite flakes [(BA) 2 (MA) 2 Pb 3 Br 10 ] has been investigated in an environmental cell. When the perovskite flakes were subjected to moderate laser irradiation in a humid environment after prior e-beam irradiation, the photoluminescence (PL) peak centered at 480 nm vanished, while a new PL peak centered at 525 nm emerged, grew, and then quenched. This indicates the degradation process of the 2D RP perovskite was a phase transition to a three-dimensional (3D) perovskite [MAPbBr 3 ] followed by the degradation of 3D perovskite. The spatial distribution of the 525 nm PL signal shows that this phase-transition process spreads across the flake to the area as far as ∼40 μm from the laser spot. Without humidity, the phase transition happened in the laser-irritated area but did not spread, which suggests that moisture enhanced the ion migration from the laser-scanned area to the rest of the flake and accelerated the phase transition in the nearby area. Experiments with no prior e-beam irradiation show that e-beam irradiation is the key to activating the 2D-3D phase transition. Therefore, when the three factors work synergistically, a conversion from the 2D RP perovskite into the 3D perovskite is not localized and propagates through the perovskite. These findings contribute to our understanding of the complex interactions between external stimuli and perovskite materials, thereby advancing the development of efficient and stable perovskite-based solar cells., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)