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In p–i–n type lead halide perovskite solar cells (PSCs), the poor wettability of the perovskite solution on the typically used hole transport layer, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), is detrimental to obtaining high quality perovskite films. Moreover, the formation of excess lead iodide (PbI2) deteriorates the device stability. Herein, by introducing diamine hydrobromides with different lengths on the PTAA layer, its wettability is greatly increased, leading to a more uniform perovskite film and reduced trap density. Moreover, diamine hydrobromide can reduce excess PbI2. Density functional theory (DFT) calculations further prove the strong interaction between diamine hydrobromides and PbI2; diamine hydrobromides with different lengths present different binding energies with PbI2. Among them, hexanediamine hydrobromate (HDADBr) has the lowest binding energy with PbI2 and enables the least traps formed in the device. Moreover, HDADBr also has the weakest interaction with the I−-rich perovskite surface, and the distribution of the I density of states is expanded, which is more conducive to the diffusion of charge carriers. The best-performing PSC is achieved when HDADBr is used, which exhibits an improved power conversion efficiency (PCE) of 20.22% from 18.41% of the control device. The device stability is also notably improved; the PCE of the unencapsulated PSC remains at 90% of the initial value after 400 h of degradation. [ABSTRACT FROM AUTHOR]

Cellulose was the most abundant biological molecule in nature, as a major component of plant cell wall. Nano cellulose Isolated through integration of cellulose fibers could be used as an adsorbent for wastewater treatment due to is excellent properties. Owing to is high cellulose content and almost without jig- nine in the cell walks, Chlorella was a good raw material for preparing Nano cellulose. In this study, Chlorella-re sexual based TEMPCoxidized cellulose nanofibers (TCNF) were prepared through TEMPC--mediated oxidation processes under gentle mixing without high-energy mechanical treatments. The average daameter of TCNF Ls a¬bout 2 nm, whereas tots average length was about 300 nm, and the carboxyl content is 1.54 moll/g. Moreover, methylene blue (MB) was used as a model dye to measure the adsorption capacity of TCNF. The adsorption capacity is almost saturated when TCNF contacted MB for 80 min, and the adsorption kinetics coincide with the pseudo-secondary kinetics model. The adsorption of TCNF on MB s greatly affected by the pH value, worth a maximum value at pH = 8. The email concentration of MB considerably affects is adsorption on TCNF. Below the INTA! Concentration of 10 mg/g, adsorption of TCNF considerably increases with the increase in the email concentration of MB. And when the concentration is higher than 10 mg/L, the adsorption tends to be saturated. Based on the scorpion isotherms analyses of TCNF, the Langmuir model its best worth the experimental data. Thus, TCNF surfaces are uniform and monolayer adsorption occurred. In conclusion, the preparation of TCNF from Chlorella-residual is a simple and promising scheme for the removal of caiiomc dyes from industrial Wastewater. [ABSTRACT FROM AUTHOR]

Broadband photodetectors have a wide range of applications in the fields of biomedical sensing, environmental monitoring, optical communications, and space exploration. Since light absorbed by MAPbX3 perovskite materials is mainly located within the visible light region, the detection range of perovskite photodetectors is limited. To broaden the detection range for these types of photodetectors and, thus, enhance the number of possible application scenarios, a non‐fullerene acceptor Y6 is introduced that strongly absorbs light in the near‐infrared band and alongside PM6 forms an organic bulk heterojunction. This results in the expansion of the absorption range due to the formation of a supplementary absorption layer onto the perovskite layer. In this paper, the effects of the newly introduced organic layer on the device performance are studied. Through the synergistic effects of the perovskite and the organic layer, a high‐performance self‐powered perovskite/organic hybrid broadband photodetector can be realized, which contains a wide detection range from ultraviolet and visible light to near‐infrared (300–1000 nm). After its optimization, the device exhibits a high external quantum efficiency value that is as high as 80% in the visible–near‐infrared band, a short response time in the region of 803/698 ns, and a large linear dynamic range of 143 dB. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) and tin-based composites along with carbon have attracted significant interest as negative electrodes for lithium-ion batteries (LIBs). However, tin-based composite electrodes have some critical drawbacks, such as high volume expansion, low capacity at high current density due to low ionic conductivity, and poor cycle stability. Moreover, complex preparation methods and high-cost carbon coating procedures are considered main challenges in the commercialization of tin-based electrodes for LIBs. In this study, we prepared a Sn/SnO2/C nano-composite structure by employing a low-cost hydrothermal method, where Sn nanoparticles were oxidized in glucose and carboxymethyl cellulose CMC was introduced into the solution. Scanning electron microscope (SEM) and transmission electron microscope revealed the irregular structure of Sn nanoparticles and SnO2 phases in the conductive carbon matrix. The as-prepared Sn/SnO2/C nano-composite showed high first-cycle reversible discharge capacity (2248 mAhg−1) at 100 mAg−1 with a first coulombic efficiency of 70%, and also displayed 474.64 mAhg−1 at the relatively high current density of about 500 mAg−1 after 100 cycles. A low-cost Sn/SnO2/C nano-composite with significant electrochemical performance could be the next generation of high-performance negative electrodes for LIBs. [ABSTRACT FROM AUTHOR]

A novel nanomaterial formed by a Cu2ZnSnS4 (CZTS)/CeO2 heterojunction with excellent electrochemical sensing for ammonia nitrogen was prepared by a microwave irradiation method combined with a hydrothermal method. The properties of the CZTS/CeO2 heterojunction were investigated by a series of characterizations such as Raman spectra, x-ray diffraction, scanning electron microscopy, thermogravimetric analysis, specific surface area (SSA), temperature-programmed desorption of ammonia and UV–vis spectroscopy. Nickel foam was used as a conductive frame electrode in order to enhance the sensitivity of the sensor along with the electrical conductivity, permeability and SSA. It is revealed by electrochemical measurements that the ammonia nitrogen oxidation reaction occurring in the sensing electrode of the CZTS/CeO2 heterojunction demonstrated regulation of Ip (mA) = 6.4 × 10−3C (mM)+ 0.1527 (R2= 0.9987) in a wide concentration range of 0–380.0 mM with a low detection of 6.0 μM according to the signal-to-noise ratio (S/N= 2). The CZTS/CeO2 heterojunction is expected to become a new candidate semiconductor nanomaterial for the electrochemical detection of ammonia nitrogen in an aqueous solution. [ABSTRACT FROM AUTHOR]

Cu2ZnSnS4 (CZTS) is a narrow band gap, non-toxic, environmentally friendly semiconductor photocatalytic material. Cu2ZnSnS4 nanoparticles were synthesized by a hydrothermal method at different temperatures. XRD and Raman results showed that CZTS with a high crystallinity kesterite structure was successfully prepared. Photoelectrochemical tests showed that CZTS is a p-type semiconductor with a band gap of 1.5 eV, and its photocurrent density could attain 0.3271 μA cm−2. It was found that CZTS had good photocatalytic activity for RhB via the photocatalysis of Rhodamine B (RhB) degradation with CZTS nanoparticles under visible light. The degradation efficiency of RhB by CZTS reached 98.20% within 90 min, and the degradation rate was about 0.02905 min−1. The photocatalytic degradation mechanism of CZTS was studied through free radical capture experiments, and results showed that photo-generated electrons could react with O2 and H2O in the solution to form ˙OH, which degraded RhB into H2O and CO2. [ABSTRACT FROM AUTHOR]

A stress‐induced failure study on a high‐temperature air‐stable ceramic composite solar selective absorber (SSA) based on a W–SiO2 system is reported. The as‐prepared SSA exhibits excellent spectral and structural stability after annealing in air at 500 °C for 36 h, proving its thermal stability against air corrosion. However, once the temperature is elevated to 600 °C, optical performance degradation and coating cracking happens. The X‐ray diffraction (XRD) patterns reveal that an O‐induced phase transition process from α‐W to β‐W occurs at the interface between the W IR reflector and W–SiO2 layer during deposition. The phase transition induces immense internal stress, which becomes the incentive of crack generation. Further increasing the annealing temperature, drastic structural changes of oxidized W become the driving force for crack propagation and hole expansion, leading to a failure analogous to a volcanic eruption. To improve the temperature limit of coating, a Ni–SiO2 stress buffer layer is introduced and successfully reduces the internal stress through Ni atom substitution for W atoms. Therefore, the optimized SSA keeps stable at 600 °C and the cracking temperature increases to 650 °C. These results suggest that the W–SiO2‐based SSA is a good candidate for air‐stable high‐temperature solar thermal conversion. [ABSTRACT FROM AUTHOR]

Adding La2O3 or CeO2 to the Ag/SiO2–ZnO catalyst can improve the catalytic performance in the synthesis of indole and CeO2 exhibits more efficiency than La2O3. La2O3 can improve the dispersion of silver on SiO2. CeO2 can improve the reduction of Ag2O. Both La2O3 and CeO2 can suppress the formation of coke. [ABSTRACT FROM AUTHOR]