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A Zn-P bond oriented black phosphorus/CuInZnS S-scheme heterojunction was successfully constructed for tetracycline (TC) degradation and synergistic H 2 generation. An enhanced photocatalytic H 2 revolution rate of 2056.0 μmol/h/g was achieved with triethanolamine (TEOA) as the hole sacrifice agent, which was nearly two times higher than that of CuInZnS (CIZS) and 170 times that of black phosphorus (BP). To further improve the hole utilization rate and reduce the energy consumption, an appropriate amount of TC was added instead of TEOA, and an improved photocatalytic H 2 generation rate of 1921.2 μmol/g was obtained with the synergistic degradation of TC by 82%. The types of heterojunctions and the transfer process of carriers were investigated by the combination of Mott-Schottky curves, Ultraviolet photoelectron spectroscopy, UV–vis diffuser reflectance spectra, and density functional theory. The results showed that a S-scheme heterojunction is built in BP/CIZS, which maintained the high redox ability of electron-hole pairs based on the successful separation of carriers. In addition, the novel Zn-P bond provided a charge transport channel and catalytic reaction active center upon photocatalysis. The design and application of photocatalysts proposed in this work offered a new idea for the coordinated resolution of environmental purification and energy conversion problems. • Zn-P bond induced BP/CIZS heterojunction was designed for waste to hydrogen conversion. • The hybrid has richer reactive sites, enhanced charge transfer and sunlight response ability. • Enhanced water splitting activity is achieved by the assistance of tetracycline. • A systematic study of photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Photocatalytic nitrogen fixation combined with degradation of organic pollutants is a promising technology to alleviate the growing energy and environmental crisis. In this work, Ti 3 C 2 T x /CuZnInS (TiC/CZIS) Schottky heterojunction difunctional photocatalytic was rationally designed for efficient nitrogen fixation synergistic bisphenol A (BPA) degradation. The Ti 3 C 2 T x ultra-thin nanosheets with richer surface-active groups and lower Fermi level greatly improved the carrier generation and separation ability of CZIS nanosphere. In addition, the coupling of TiC extended the absorption of CZIS to infrared region, which provided the possibility of efficient photocatalytic activity in cloudy and rainy days. As a result, an enhanced photocatalytic nitrogen fixation activity of 45.6 μmol/g/h was achieved. It should be noted that once appropriate amount of BPA was introduced to the photocatalytic system, a satisfied activity of 82.5 μmol/g/h was obtained, BPA can also be degraded by 58.5% within 180 min by TiC/CZIS. Through a series of experimental characterizations, the photocatalytic active substances and degradation pathway of BPA was investigated, and the possible photocatalytic mechanism was established. This work lays a foundation for the design of environmentally friendly photocatalysts and their applications in the fields of environmental purification and energy conversion. [Display omitted] • Ti 3 C 2 T x decorated CuZnInS was designed for waste to energy conversion. • The hybrid has richer reactive sites, enhanced charge transfer and sunlight response ability. • Enhanced nitrogen fixation activity is achieved by the assistance of BPA. • A systematic study of photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Studying the exciton dissociation is the key to revealing the photocatalytic mechanism. • The exciton-rich properties of BP QDs have special advantages in the process of charge separation. • BP QDs have many-body effect, short carrier transport distance and abundant reaction sites. • The BP/TiO 2 heterojunction exhibits excellent H 2 production efficiency (112 μmol·h−1·g−1). The Coulomb interactions between excited electrons and holes have a very important influence on the photophysical processes in 2D semiconductors. Exciton dissociation is one of the key steps that significantly contribute to the efficiency of photocatalysis, but its research in the relevant aspects of photocatalysis has not been in-depth. Herein, the BP/TiO 2 heterojunction as a prototypical model system was constructed on the surface of urchin-like TiO 2 where black phosphorous (BP) quantum dots (QDs) grew. The BP/TiO 2 heterojunction exhibits an improved H 2 -production rate of 112 μmol·h−1·g−1 under UV–visible light irradiation without any cocatalysts, which is 2.4 times higher than that of pure TiO 2 (47 μmol·h−1·g−1). As a typical exciton-rich material, BP QDs have special advantages on the charge separation process, because of their prominent many-body effect, short carrier transport distance, and large specific surface with rich reactive sites. The energy difference between the conduction bands turns out to be the driving force for exciton dissociation in the BP/TiO 2 heterojunction. The theoretical calculation implies that the excited electron tends to transfer from BP QD to TiO 2. The high catalytic performance of heterojunction contributes to the effective exciton dissociation, interfacial charge separation, and charge-carrier accumulation. This work lays the foundation for the design of the BP QDs based photocatalytic system and its application in photocatalytic hydrogen production and provides an effective reference for increasing the active sites of heterojunctions. [ABSTRACT FROM AUTHOR]

[Display omitted] Design of highly efficient heterojunctions for photocatalytic hydrogen evolution is of significant importance to address the energy shortage and environmental crisis. Nevertheless, the smart design of semiconductor-based heterojunctions at the atomic scale still remains a significant challenge hitherto. Herein, we report novel atomic CdS/ZnIn 2 S 4 heterojunctions by in-situ epitaxially growing 2D ZnIn 2 S 4 nanosheets onto the surface of 1D defective CdS nanorods. The strong electronic coupling between defective CdS and ZnIn 2 S 4 is confirmed by transient photocurrent response measurements, •O 2 − and •OH radicals experiments, and PL results, leading to accelerated interfacial charge separation and transfer. Additionally, the elevated charge transfer and electronic coupling are further confirmed by theoretical calculations. Consequently, CdS/ZnIn 2 S 4 hybrids exhibit superior photocatalytic hydrogen generation activity to pristine CdS. Our findings offer a new paradigm for designing atomic 1D/2D heterojunctions for efficient solar-driven energy conversion. [ABSTRACT FROM AUTHOR]