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The continuous process for the production of insoluble sulfur (IS) has been developed to overcome the disadvantages associated with the traditional batch process, such as low automation, discontinuous production, and high consumption of sulfur and CS2. The consumption of CS2 in the continuous process is lower than that in the batch process. The recovery of solvent facilitates the recycling of CS2 and N2 in addition to the closed circulation of the entire system. The key process and recovery parameters of the IS synthesis were simulated using Aspen Plus. Sulfur was completely recovered after high-temperature pyrolysis, and the utilization ratio of sulfur atoms was increased from approximately 50% to more than 95%. Tail gas was comprehensively utilized through compression and cryogenic green treatment. Based on the developed green synthesis process and simulated process parameters, the continuous production of IS was evaluated on an industrial scale of 10,000 metric tonnes. Owing to the continuous characteristics of the production process, the air tightness of the production process was significantly improved, and the quality of the product was more stable than that of the product obtained by the current domestic batch process. The unconverted sulfur could be recycled after recovery, without low-grade sulfur as a by-product. The amount of sulfur used as raw material per unit product was reduced; the comprehensive conversion rate of sulfur to IS exceeded 95%, which significantly improved the utilization rate of sulfur atoms. Through the compression and condensation of the tail gas, the recovery efficiency of CS2 was considerably improved at the same temperature, and compressed N2 could be simultaneously obtained. The liquefaction rate of CS2 approached 91.78%, which was characterized by obvious greening.

Accurate and quantifiable detection of the specific wavelength is vital in different application scenarios. Herein, a novel self‐driven narrowband photodetector (NB‐PD) based on CH(NH2)2PbBr2.5I0.5 crystal film is employed for building a yellow light intensity meter. By taking advantage of the carrier collection narrowing mechanism, a sensitive NB‐PD with peak response at 580 nm and the full‐width at half‐maximum of 23 nm are successfully achieved. The asymmetric contact electrodes of Ag/Pt allow the device to work without bias. The optoelectronic analysis demonstrates that the NB‐PD achieves a maximum responsivity of 59.89 mA W−1, a fast response speed of 202/331 µs, and a high on/off ratio of 636 at zero bias. Then, through introducing the back‐end circuit, a yellow light intensity meter is constructed with the NB‐PD. The absolute error and relative error of the light meter are estimated to be lower than 0.08 mW cm−2 and 4.22%, respectively, indicating the good capability for the yellow light monitoring. Given the simple device geometry and good performance, the achieved yellow light intensity meter can also be extended to other narrowband light detection system. [ABSTRACT FROM AUTHOR]

A narrowband photodetection system that can specifically distinguish green, yellow and red light has potential application in intelligent transportation systems. In this work, a series of MAPbBr3−nXn (X = Cl, I) single-crystal films with controllable thickness have been grown through space-limited inverse temperature crystallization. Filter-free narrowband photodetectors with peak responses at 505, 590 and 620 nm, corresponding to the green, yellow and red of traffic lights, are successfully achieved through the charge collection narrowing mechanism. The as-fabricated narrowband photodetectors demonstrate superior performance, with full width at half-maximum all less than 35 nm, a maximum responsivity of 182 mA W−1, and specific detectivity of 9.68 × 1010 Jones. Finally, a traffic light recognition assembly based on the three narrowband photodetectors is constructed. The photocurrent of the photodetector is approximately five to ten times that of the interference from other light sources, indicating good color recognition capability for traffic lights. [ABSTRACT FROM AUTHOR]