As a sustainable technology that can be utilized for degrading organic pollutants, photocatalysis becomes more and more important in the environment pollution control. One crucial factor that influences the degradation process is the design of photocatalyst. In this study, we utilized a simple hydrothermal method, liquid exfoliation and mechanical mixture to synthesize a novel S-scheme heterojunction based on BiPO 4 /CdPSe 3 . It was found that the optimal molar ratio BiPO 4 : CdPSe 3 = 2: 1 (noted as B 2 C) gave rise to an efficient removal of rhodamine B up to 97.5 % after 30 min dark reaction and 60 min light exposure. This composite also possesses the degradation capacity for other antibiotics and inorganic pollutant. The capture experiments showed that superoxide radicals played the dominant role in the degradation process. Besides, hydroxyl radicals and holes were also important active species. The high photocatalytic degradation performance of B 2 C could be attributed to the increased specific surface area with more active sites, enhanced light absorption in the visible region, and, more importantly, the special S-scheme heterostructure for high photogenerated charge carrier separation, synergistically improved the photocatalyst degradation efficiency. This work provides a new perspective for designing high-efficient photocatalysts applicable in multiple organic and inorganic pollutants degradation.
Transition metal thiophosphates (MTPs) are a group of emerging van der Waals materials with widely tunable band gaps. In the MTP family, CdPSe3 is demonstrated to possess a wide energy band gap and high carrier mobility, making it a potential candidate in optoelectronic applications. Here, we reported photoelectric response behaviors of both CdPSe3- and CdPSe3/MoS2-based photodetectors (noted as CPS and CM, respectively); these showed prominent photoelectric performances, and the latter proved to be significantly superior to the former. These devices exhibited ultralow dark current at a magnitude order of 10–12 A and fine cycle and air stabilities. Compared with CPS, CM demonstrated the highest responsivity (91.12 mA/W) and detectivity (1.74 × 1011 Jones) at 5 V under 425 nm light illumination. Besides, CM showed self-powered photoelectric responses at zero bias, which was attributed to the improved separation efficiency of photogenerated carriers by the built-in electric field at the interface of the p–n junction. This work proves a prospect for the CM device in portable, self-powered optoelectronic device applications.
Photocatalysis offers a green and sustainable route for pollutant degradation, with the performance of photocatalysts being a critical factor. Recently, van der Waals materials have gained increasing attention in this field due to their favorable photocatalytic properties. In this study, a novel Ag/CdPSe3 composite was synthesized via chemical vapor transport, liquid-phase exfoliation, and liquid-phase chemical reduction methods. When the Ag:CdPSe3 molar ratio was optimized to 2:1 (denoted A2C1), the composite achieved a tetracycline hydrochloride removal efficiency of 91.69% within 60 min of illumination─1.99 times that of CdPSe3. The A2C1 composite also exhibited effective photocatalytic degradation toward multiple antibiotics, including ciprofloxacin, norfloxacin, and amoxicillin, demonstrating its broad-spectrum application potential. Trapping experiments identified photogenerated holes as the dominant active species, with superoxide radicals playing supporting roles. Mechanistic studies revealed that Ag modification enhanced light absorption in the near-infrared and partial visible regions, while the Schottky junction formed at the Ag/CdPSe3 interface facilitated efficient photogenerated carrier separation. Together, these factors contribute to the superior photocatalytic performance of A2C1. This work provides new insights into the design of high-performance photocatalysts based on van der Waals materials.