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The threat of environmental microbial contamination to the health of human beings has drawn particular attention. In order to explore the synergistic effect of photocatalytic and photothermal process to the antibacterial property, a stably combined BiOI-graphene oxide (GO) nanocomposite was constructed and prepared through a facile solvothermal method. BiOI crystals were uniformly distributed on the GO nanosheets by the formation of the Bi−C bond. On the basis of various characterizations, the great surface area, the high light harvesting with extension into NIR region, and the efficient transfer of photoinduced electrons by the conductivity of GO were demonstrated, all of which are beneficial for the photocatalytic antibacterial activity. More importantly, the photothermal effect of GO increased the temperature of the BiOI-GO composite with high photothermal conversion efficiency and induced the photogenerated electrons from BiOI crystals to obtain more energy and higher carrier mobility. Conversely, the temperature elevation of BiOI-GO composite improved its capability for light absorption and separation of photoinduced charges. As a result, the BiOI-GO composite enabled the synergistic photocatalytic-photothermal effect for the improvement of the antibacterial property for Acinetobacter baumannii with higher efficiency of TOC removal and leakage of K + ions, in comparison with the individual photocatalytic process. Thus, the synergistic photocatalytic-photothermal contribution of BiOI-GO composite will provide significance for the potential application of environmental disinfection in the future.

energy crisis and greenhouse effect caused by the excessive use of fossil fuels. [1] Graphite carbon nitride (g-C 3 N 4 ) is regarded as one of the most promising photocatalysts due to its facile preparation, unique layered structure, and inherently visible light absorption. [2] However, pristine g-C 3 N 4 also suffers from a high photoexcited charge carrier recombination rate and limited visible light absorption range, resulting in undesirable photocatalytic H 2 production. Among various modification strategies, non-metallic element doping is considered to be one of the most economical and effective methods. [3] It can not only effectively improve the visible light response, but also induce electron rearrangement, which is beneficial to H 2 O adsorption and dissociation of OHH. Numerous reports have shown that doping with non-metallic elements, such as S, P, O, and B, can effectively improve hydrogen evolution performance. [4] The conjugated π bond in g-C 3 N 4 makes it difficult to replace the C and N of the melon unit. Therefore, a high-temperature calcination method is often used to prepare doped g-C 3 N 4 . [5] Interestingly, heteroatom doping is prone to a ring-opening reaction, which is often accompanied by the generation of defects. [2a,5b] Although both doping and defect engineering can enhance photocatalytic activity, the unregulated doping sites and inappropriate defect concentrations and types still result in performance losses. It is theoretically believed that photocatalysis performance can be further improved by precisely adjusting the correlation between the defect location and the non-metallic heteroatom.It is generally believed that the nitrogen vacancy (V N ) has a charge in g-C 3 N 4 , which is conducive to the adsorption of heteroatom reagents. Therefore, directional doping of heteroatoms can be achieved by the construction of nitrogen vacancies. Nitrogen vacancies in g-C 3 N 4 have been reported to facilitate the hydrogen evolution reaction (HER) in photocatalysis by increasing bulk carrier concentration. [6] However, vacancy concentration and photocatalytic efficiency are not linearly related. Numerous reports have shown that the hydrogen production activity of samples first increases and then decreases with increasing defect concentration. [7] At present, researchers have reached a consensus on the mechanism of photocatalysis improvement by defect engineering: an appropriate amount of nitrogen vacancies can capture electrons and accelerate the Traditional defect engineering and doping strategies are considered effective means for improving H 2 evolution, but the uncontrollability of the modification process does not always lead to efficient activity. A defect-induced heteroatom refilling strategy is used here to synthesize heteroatoms introduced carbon nitride by precisely controlling the "introduction" sites on efficient N1 sites. Density functional theory calculations show that the refilling of B, P, and S sites have stronger H 2 O adsorption and dissociation capacity than tradition...