Network analysis reveals context-dependent structural complexity of social calls in serrate-legged small treefrogs.

Vocal communication plays an important role in survival, reproduction, and animal social association. Birds and mammals produce complex vocal sequence to convey context-dependent information. Vocalizations are conspicuous features of the behavior of most anuran species (frogs and toads), and males usually alter their calling strategies according to ecological context to improve the attractiveness/competitiveness. However, very few studies have focused on the variation of vocal sequence in anurans. In the present study, we used both conventional method and network analysis to investigate the context-dependent vocal repertoire, vocal sequence, and call network structure in serrate-legged small treefrogs Kurixalus odontotarsus. We found that male K. odontotarsus modified their vocal sequence by switching to different call types and increasing repertoire size in the presence of a competitive rival. Specifically, compared with before and after the playback of advertisement calls, males emitted fewer advertisement calls, but more aggressive calls, encounter calls, and compound calls during the playback period. Network analysis revealed that the mean degree, mean closeness, and mean betweenness of the call networks significantly decreased during the playback period, which resulted in lower connectivity. In addition, the increased proportion of one-way motifs and average path length also indicated that the connectivity of the call network decreased in competitive context. However, the vocal sequence of K. odontotarsus did not display a clear small-world network structure, regardless of context. Our study presents a paradigm to apply network analysis to vocal sequence in anurans and has important implications for understanding the evolution and function of sequence patterns.

Collective effects of rising average temperatures and heat events on oviparous embryos.

Survival of the immobile embryo in response to rising temperature is important to determine a species' vulnerability to climate change. However, the collective effects of 2 key thermal characteristics associated with climate change (i.e., rising average temperature and acute heat events) on embryonic survival remain largely unexplored. We used empirical measurements and niche modeling to investigate how chronic and acute heat stress independently and collectively influence the embryonic survival of lizards across latitudes. We collected and bred lizards from 5 latitudes and incubated their eggs across a range of temperatures to quantify population-specific responses to chronic and acute heat stress. Using an embryonic development model parameterized with measured embryonic heat tolerances, we further identified a collective impact of embryonic chronic and acute heat tolerances on embryonic survival. We also incorporated embryonic chronic and acute heat tolerance in hybrid species distribution models to determine species' range shifts under climate change. Embryos' tolerance of chronic heat (T-chronic) remained consistent across latitudes, whereas their tolerance of acute heat (T-acute) was higher at high latitudes than at low latitudes. Tolerance of acute heat exerted a more pronounced influence than tolerance of chronic heat. In species distribution models, climate change led to the most significant habitat loss for each population and species in its low-latitude distribution. Consequently, habitat for populations across all latitudes will shift toward high latitudes. Our study also highlights the importance of considering embryonic survival under chronic and acute heat stresses to predict species' vulnerability to climate change.

Efectos colectivos del aumento de las temperaturas promedio y los eventos de calor en embriones ovíparos Resumen La supervivencia de los embriones inmóviles en respuesta al incremento de temperatura es importante para determinar la vulnerabilidad de las especies al cambio climático. Sin embargo, los efectos colectivos de dos características térmicas claves asociadas con el cambio climático (i. e., aumento de temperatura promedio y eventos de calor agudo) sobre la supervivencia embrionaria permanecen en gran parte inexplorados. Utilizamos mediciones empíricas y modelos de nicho para investigar cómo el estrés térmico crónico y agudo influye de forma independiente y colectiva en la supervivencia embrionaria de los lagartos en todas las latitudes. Recolectamos y criamos lagartos de cinco latitudes e incubamos sus huevos en un rango de temperaturas para cuantificar las respuestas específicas de la población al estrés por calor crónico y agudo. Posteriormente, mediante un modelo de desarrollo embrionario parametrizado con mediciones de tolerancia embrionaria al calor, identificamos un impacto colectivo de las tolerancias embrionarias al calor agudo y crónico en la supervivencia embrionaria. También incorporamos la tolerancia embrionaria crónica y aguda al calor en modelos de distribución de especies híbridas para determinar los cambios de distribución de las especies bajo el cambio climático. La tolerancia embrionaria al calor crónico (T­crónico) permaneció constante, mientras que la tolerancia al calor agudo (T­agudo) fue mayor en latitudes altas que en latitudes bajas. La tolerancia al calor agudo ejerció una influencia más pronunciada que la tolerancia al calor crónico. En los modelos de distribución de especies, el cambio climático provocó la pérdida de hábitat más significativa para cada población y especie en su distribución de latitudes bajas. En consecuencia, el hábitat para poblaciones en todas las latitudes se desplazará a latitudes altas. Nuestro estudio también resalta la importancia de considerar la supervivencia embrionaria bajo estrés térmico crónico y agudo para predecir la vulnerabilidad de las especies al cambio climático.

Heterospecific eavesdropping on disturbance cues of a treefrog.

Alarm signals and cues are crucial to animal survival and vary greatly across species. Eavesdropping on heterospecific alarm signals and cues can provide eavesdroppers with information about potential threats. In addition to acoustic alarm signals, evidence has accumulated that chemical alarm cues and disturbance cues can also play a role in alerting conspecifics to potential danger in adult anurans (frogs and toads). However, there is very little known about whether disturbance cues are exploited by heterospecifics. In the present study, we conducted a binary choice experiment and a prey chemical discrimination experiment, respectively, to test the responses of a sympatric anuran species (red webbed treefrogs, Rhacophorus rhodopus) and a sympatric predator species (Chinese green tree vipers, Trimeresurus stejnegeri) to disturbance odors emitted by serrate-legged small treefrogs (Kurixalus odontotarsus). In the binary choice experiment, we found that the presence of disturbance odors did not significantly trigger the avoidance behavior of R. rhodopus. In the prey chemical discrimination experiment, compared with odors from undisturbed K. odontotarsus (control odors) and odorless control, T. stejnegeri showed a significantly higher tongue-flick rate in response to disturbance odors. This result implies that disturbance odor cues of K. odontotarsus can be exploited by eavesdropping predators to detect prey. Our study provides partial evidence for heterospecific eavesdropping on disturbance cues and has an important implication for understanding heterospecific eavesdropping on chemical cues of adult anurans.

Four new compounds from the fruits of Chinese dwarf cherry (Prunus humilis Bunge).

A new flavonoid (bunge A) (1), a new sesquiterpene (bunge B) (8), a new furan derivative (bunge C) (12) and a new alkenoic acid (bunge D) (14), together with ten known ones [four flavonoids (2, 3, 4, 5), two phenylpropanoids (6, 7), three sesquiterpenes (9, 10, 11) and one lactone (13)] were isolated from the fruits of Prunus humilis Bunge [Cerasus humilis (Bunge) Sokolov]. Their structures were elucidated based on extensive spectroscopic analysis (including HR-ESI-MS and NMR) and comparison with previously published data. All compounds were evaluated for cytotoxic activity against three human tumour cell lines. Compound 3 and 4 showed weak antiproliferative activities against hepatocarcinoma cell HepG-2 at the concentration of 100 µM, which the inhibition rates were 55.34 ± 0.29 and 45.52 ± 0.37, respectively. And other compounds had almost no cytotoxic activity against the three tumour cell lines in vitro.

Porphyrin-based conjugated organic polymer with dual metal sites for highly active and selective visible-light-driven reduction of CO2 to CO.

A porphyrin-based conjugated organic polymer (COP) was constructed from 5,10,15,20-tetrakis(4-bromophenyl)porphyrin copper (CuTBPP) and 5,5'-bis-ethynyl-2,2'-bipyridine (BPY) via Sonogashira coupling. Its complex Co/CuTBPP-BPY-COP (with dual metal sites composed of copper porphyrin and a cobalt BPY unit) was prepared by coordination with Co2+. All of the prepared CuTBPP-BPY-COP and Co/CuTBPP-BPY-COP compounds exhibited excellent photocatalytic performance toward CO2 reduction under visible-light irradiation without another sacrificial reagent but only H2O. Co/CuTBPP-BPY-COP (dual metal sites) exhibited better photocatalytic activity than CuTBPP-BPY-COP (a single metal site). Co/CuTBPP-BPY-COP retained a higher photocatalysis capacity for CO2 reduction after 10 consecutive cycles. The total quantity of CO product was 263.2 µmol g-1 after 10 h of irradiation. Theoretical studies indicate that introducing Co metal centers and nitro groups are more favorable for the photoreduction catalysis of CO2 compared with that using CuTBPP-BPY-COP.

Cu Nanoparticles Modified Step-Scheme Cu2O/WO3 Heterojunction Nanoflakes for Visible-Light-Driven Conversion of CO2 to CH4.

In this study, Cu and Cu2O hybrid nanoparticles were synthesized onto the WO3 nanoflake film using a one-step electrodeposition method. The critical advance is the use of a heterojunction consisting of WO3 flakes and Cu2O as an innovative stack design, thereby achieving excellent performance for CO2 photoreduction with water vapor under visible light irradiation. Notably, with the modified Cu nanoparticles, the selectivity of CH4 increased from nearly 0% to 96.7%, while that of CO fell down from 94.5% to 0%. The yields of CH4, H2 and O2 reached 2.43, 0.32 and 3.45 mmol/gcat after 24 h of visible light irradiation, respectively. The boosted photocatalytic performance primarily originated from effective charge-transfer in the heterojunction and acceleration of electron-proton transfer in the presence of Cu nanoparticles. The S-scheme charge transfer mode was further proposed by the in situ-XPS measurement. In this regard, the heterojunction construction showed great significance in the design of efficient catalysts for CO2 photoreduction application.

A new snake species of the genus Gonyosoma Wagler, 1828 (Serpentes: Colubridae) from Hainan Island, China.

A new species of the genus Gonyosoma Wagler, 1828 is described herein based on six specimens from the Diaoluoshan Mountains, Hainan Island, Hainan Province, China. The new species, Gonyosoma hainanensesp. nov., is most similar to its continental sister species, Gonyosoma boulengeri (Mocquard, 1897). Both taxa have a scaled protrusion on the anterior portion of the rostrum, distinct from other congeners. However, Gonyosoma hainanensesp. nov. can be distinguished from G. boulengeri by two significant morphological characters: (1) black orbital stripe absent in adults (vs. present in G. boulengeri); and (2) two loreals (vs. one loreal in G. boulengeri). The new species is also genetically divergent and forms a unique clade from its sister species and all other congeners based on sequences of the mitochondrial gene cytochrome b (cyt b).

Conspecific odor cues induce different vocal responses in serrate-legged small treefrogs, but only in the absence of acoustic signals.

BACKGROUND: Signal detection is crucial to survival and successful reproduction, and animals often modify behavioral decisions based on information they obtained from the social context. Undeniably, the decision-making in male-male competition and female choice of anurans (frogs and toads) depends heavily on acoustic signals. However, increasing empirical evidence suggests that additional or alternative types of cue (e.g., visual, chemical, and vibratory) can be used to detect, discriminate and locate conspecifics in many anuran species. Nevertheless, few studies have investigated whether conspecific odor cues affect male's calling behavior. In this study, we conducted an experiment to investigate whether and how different chemical cues (male odors, female odors, and stress odors) from conspecifics affect male's calling strategies in serrate-legged small treefrogs (Kurixalus odontotarsus), and whether the combined chemical and acoustic stimuli have additive effects on calling behavior or not. RESULTS: We found that compared with female odors, male K. odontotarsus reduced calling investment in response to male odors or stress odors, in the absence of rival's advertisement calls. When odor stimuli and advertisement calls were presented simultaneously, however, there were no differences in the vocal response of focal males among odor groups. CONCLUSIONS: These results provide evidence that male treefrogs switch calling investment according to different odor cues from conspecifics, and further demonstrate that calling behavior can be affected by chemical cues in anuran species. Our study highlights the potential role of airborne chemical cues in sex identification and contributes to increase our understanding of anuran communication.

pH-controlled mechanism of photocatalytic RhB degradation over g-C3N4 under sunlight irradiation.

Photocatalysis of dye degradation is one of green and cheap technologies for solving environmental pollution. Whereas it is rarely concerned that the degradation process varied with the change of solution condition, this work studied the influence of hydrion in the solution on the photodegradation process of Rhodamine B (RhB) over g-C3N4. The photocatalytic activity of RhB degradation was enhanced gradually with increased hydrion content in the system. The efficiency for RhB degradation over g-C3N4 in weak acidic system with interference of multiple metal-ions still reached near 95% after 30 min of natural sunlight irradiation. A large amount of oxidation species and the hydroxylation mineralization process were induced by increasing the hydrion concentration. Two degradation processes for deethylation of four ethyl groups and the direct chromophoric degradation were discovered and proved by multifarious intermediates in different systems using the ESR technique, LC/MS and GC/MS analysis. In addition, the photosensitization played a critical role in the RhB degradation. A feasible degradation mechanism was proposed for the RhB degradation based on the experimental results.

Anticancer Drug Release System Based on Hollow Silica Nanocarriers Triggered by Tumor Cellular Microenvironments.

Targeted release of anticancer drugs to tumor sites has a pivotal role in clinical oncology. pH-responsive drug delivery systems, with an intelligent and targeted release of anticancer drugs in a controllable manner based on sensitivities to the weakly acidic environments of tumor cellular microenvironments, are desirable. Herein, the design of such a pH-responsive drug delivery system is detailed using in situ amino-functionalized hollow mesoporous silica nanoparticles as carriers. The drug release behavior of the pH-responsive delivery system was evaluated under an in vitro simulation of tumor cellular microenvironments. The drug delivery system has efficient drug loadings and targeted release. Zorubicin hydrochloride releasing percentage is almost up to 100% at a buffer pH of 5.0. The drug release systems described demonstrating great potential in anticancer therapy.

Outcomes of Dura Splitting Decompression Versus Posterior Fossa Decompression With Duraplasty in the Treatment of Chiari I Malformation: A Systematic Review and Meta-analysis.

BACKGROUND: Surgery is the definitive treatment option for symptomatic Chiari malformation I (CMI), but there is no clear consensus as to the preferred surgical method. This study aimed to quantitatively assess and compare the effect and safety of dura splitting decompression (DSD) and posterior fossa decompression with duraplasty (PFDD) in treating patients with CMI. METHODS: A literature search of EMBASE, MEDLINE, PubMed, Cochrane Library, and Web of Science databases was conducted. References from January 1990 to September 2020 were retrieved. We only included papers containing original data, comparing the use of DSD and PFDD in CMI patients. RESULTS: Overall, 11 relevant studies were identified, wherein 443 patients treated for CMI by DSD were compared with 261 patients treated by PFDD. No difference was observed between PFDD and PFD in terms of clinical improvement (P = 0.69), syringomyelia improvement (P = 0.90), or reoperation (P = 0.22). DSD was associated with shorter operation durations (P = 0.0007), shorter length of stay (P = 0.0007), and shorter overall postoperative complications (P < 0.0001) (especially cerebrospinal fluid [CSF] leak [P = 0.005], meningitis [P = 0.002], and pseudomeningocele [P = 0.002]), as compared with PFDD. CONCLUSIONS: This study confirmed that dura splitting decompression has clinical and syringomyelia improvement outcomes comparable to posterior fossa decompression with duraplasty. Compared with PFDD, DSD not only significantly shortened the operation time and length of stay, but also significantly reduced the overall complication rate, especially those related to incidence of CSF-related complications. More evidence from advanced multicenter studies are needed to require to validate the findings.

Male serrate-legged treefrogs adjust competition strategies according to visual or chemical cues from females.

There is increasing evidence that many anurans use multimodal cues to detect, discriminate and/or locate conspecifics and thus modify their behaviors. To date, however, most studies have focused on the roles of multimodal cues in female choice or male-male interactions. In the present study, we conducted an experiment to investigate whether male serrate-legged small treefrogs (Kurixalus odontotarsus) used visual or chemical cues to detect females and thus altered their competition strategies in different calling contexts. Three acoustic stimuli (advertisement calls, aggressive calls and compound calls) were broadcast in a randomized order after a spontaneous period to focal males in one of four treatment groups: combined visual and chemical cues of a female, only chemical cues, only visual cues and a control (with no females). We recorded the vocal responses of the focal males during each 3 min period. Our results demonstrate that males reduce the total number of calls in response to the presence of females, regardless of how they perceived the females. In response to advertisement calls and compound calls, males that perceived females through chemical cues produced relatively fewer advertisement calls but more aggressive calls. In addition, they produced relatively more aggressive calls during the playback of aggressive calls. Taken together, our study suggests that male Kodontotarsus adjust their competition strategies according to the visual or chemical cues of potential mates and highlights the important role of multisensory cues in male frogs' perception of females.

Metal-free azo-bridged porphyrin porous organic polymers for visible-light-driven CO2 reduction to CO with high selectivity.

Two nitrogen-rich azo-bridged porphyrin porous organic polymers (Azo-Por-Bpy-POP and Azo-Por-Dadp-POP) with high surface areas were prepared by coupling 5,10,15,20-tetra(p-nitrophenyl)-porphyrin with the aromatic amines of 2,2'-bipyridine-5,5'-diamine (Bpy) and diaminodiphenyl (Dadp). Azo-Por-Bpy-POP and Azo-Por-Dadp-POP display high photocatalytic reduction activity for CO2 to CO under visible-light irradiation without a sacrificial reagent or metal co-catalyst. Azo-Por-Bpy-POP exhibits the highest photoreduction for CO2 with CO as the only carbonaceous reduction product with a production rate of 38.75 µmol g-1 h-1. Theoretical investigations indicate a stronger electrostatic interaction between CO2 and Azo-Por-Bpy-POP than Azo-Por-Dadp-POP, which favors CO2 photoreduction.

Enhanced Photo-Assisted Acetone Gas Sensor and Efficient Photocatalytic Degradation Using Fe-Doped Hexagonal and Monoclinic WO3 Phase-Junction.

The development of WO3-based gas sensors for analysis of acetone in exhaled breath is significant for noninvasive diagnosis of diabetes. A series of Fe-doped hexagonal and monoclinic WO3 phase-junction (Fe-h/m-WO3) sensors were synthesized by the hydrothermal calcination method, and the influences of operating temperature and light irradiation on the response were studied. Under light emitting diode (LED) illumination, Fe-h/m-WO3 exhibited higher responses to acetone than those of the undoped WO3-based sensors at an operating temperature of 260 °C with 90% relative humidity, and good linearity between response and acetone concentration (0.5 to 2.5 ppm) was achieved under the 90% relative humidity condition. Meanwhile, the optimal Fe-h/m-WO3 sensor exhibited high selectivity and stability for a duration of three months. The excellent sensing performance of Fe-h/m-WO3 was attributed to the formation of phase-junction and Fe doping, and these were beneficial for the separation of photon-generated carriers and oxygen adsorption on the WO3 surface, promoting the generation of superoxide radicals, which was demonstrated by electron paramagnetic resonance and photocurrent tests. Additionally, the Fe-doped WO3 phase-junction sample also showed good photocatalytic performance for rhodamine B degradation. This study may provide some insights into rational design of new types of gas sensors and offer an alternative for noninvasive diagnosis of diabetes.

Mate choice decisions of female serrate-legged small treefrogs are affected by ambient light under natural, but not enhanced artificial nocturnal light conditions.

Artificial light at night (ALAN) is a widespread anthropogenic stimulus that can significantly alter nocturnal animals' behavior, from migration to foraging to vocal communication. In the present study, we tested the hypothesis that the mate choice decisions of female serrate-legged small treefrogs (Kurixalus odontotarsus) were influenced by ambient light intensity. Standard two-speaker phonotaxis tests were conducted in a sound attenuating chamber. We set four light treatments (I-IV, from low to high) based on a range of light intensities from the maximum natural light at night (i.e., full moon) to that of the actual calling sites, which had artificial light. Contrary to our prediction, female frogs showed a preference for calls on the bright side in treatment I when they were exposed to identical stimuli. However, females preferred longer calls on the dim side to shorter calls on the bright side in this treatment. In addition, there were no significant effects of choice side, light treatment or their interaction on leave time or choice time. Our results suggest that females are more attracted to mates in bright light under natural nocturnal light conditions, but the preference for longer calls is not altered in serrate-legged small treefrogs.

A hybrid of g-C3N4 and porphyrin-based covalent organic frameworks via liquid-assisted grinding for enhanced visible-light-driven photoactivity.

Designing photocatalysts with heterostructures is an effective way to promote visible-light-driven photocatalytic degradation. Herein, a series of 2D/2D heterojunction photocatalysts, denoted as CuPor-Ph-COF/g-C3N4 composites, were prepared through in situ synthesis on the surface of g-C3N4 by a facile liquid-assisted grinding method. The photocatalytic performance of the as-prepared CuPor-Ph-COF/g-C3N4 composites was evaluated by the degradation of a model pollutant rhodamine B. The CuPor-Ph-COF/g-C3N4 composites displayed superior photocatalytic performance to pure g-C3N4 or pure CuPor-Ph-COF because of the faster separation of photogenerated charges. This represents the first composite fabricated between a 2D porphyrin-based covalent organic framework (COF) and g-C3N4, demonstrating not only the possibility but also more importantly the affordability of the application of costly porphyrin-based COFs in catalysis.

A novel synthesis of oleophylic Fe2O3/polystyrene fibers by γ-Ray irradiation for the enhanced photocatalysis of 4-chlorophenol and 4-nitrophenol degradation.

Photocatalytic degradation by efficient and easy recyclable semiconductor-catalysts is an ideal way to solve the environmental problem. A series of Fe2O3/Polystyrene (Fe2O3/PS) composite fibers with hydrophobic property were obtained by the electrospinning and γ-Ray irradiation methods. The γ-Ray irradiation treatment not only formed steady micro-nano construction of nanoparticles and fiber, but also reduced the hydroxyl group on Fe2O3 surface. The high photocatalytic efficiencies of Fe2O3/PS fiber were discovered with the high content of 4-chlorophenol (4-CP) and 4-nitrophenol (4-NP), due to the synergetic effect of adsorption and degradation. The suitable adsorption capacity of Fe2O3/PS could promote the utilization of the generated hydroxyl radical(OH) to directly oxidize the adsorbed pollutant molecules. Additionally, the photocatalytic activities for 4-CP and 4-NP still reached 80% and 75% in the 6th cycling and the composite fiber exhibited the good recyclability, which has the application development prospect for wastewater treatment. The mechanism of 4-CP and 4-NP decomposition was verified. Hence, the gained results could provide some insights into phenol degradation over the multifunctional and efficient catalyst.

Fast and Simple Fabrication of Superhydrophobic Coating by Polymer Induced Phase Separation.

Polymerization-induced phase separation is comparatively applied to fabricating a superhydrophobic micro/nano surface by microwave and ultraviolet (UV) irradiation. The monolithic coatings can be tailored easily on different substrates with excellent chemical and mechanical stability in rigid conditions. Importantly, the patterned filter paper is successfully used for the colorimetric detection of nitrite handily.

Natural sunlight driven highly efficient photocatalysis for simultaneous degradation of rhodamine B and methyl orange using I/C codoped TiO2 photocatalyst.

Increasing the efficiency of dye degradation is a critical issue for the application for photocatalysis. It is one of the greatest challenges to enhance the utilization of photo generated carriers in semiconductor, especially for sunlight irradiation. In this study, I/C-codoped TiO2 was synthesized by a simple solvothermal-calcination method. The codoping interstitial carbon and substitutional iodine not only widened the light absorption range of the TiO2 photocatalysts, but also enhanced the separation of photo-induced carriers. The photocatalytic activities of RhB and MO degradation over the 4-I/C-TiO2 photocatalyst could reach 98.2% and 94.2% after 25 min visible light irradiation (λ ≥ 400 nm), respectively. Notably, 4-I/C-TiO2 showed good activity for MO and RhB mixed degradation and could also accomplish the photocatalytic degradation in the above mixed system under natural sunlight irradiation. According to the dark catalytic experiment, I/C-codoping could effectively accelerate the formation of hydroxyl radicals from the generated H2O2, which was formed for the enhanced photocatalytic activity of dye degradation. The gained knowledge may provide some insights into the photocatalytic degradation over the codoped TiO2 catalyst.

Porous Mn doped g-C3N4 photocatalysts for enhanced synergetic degradation under visible-light illumination.

Photocatalytic degradation by semiconductors is an ideal way to solve the environmental problem. Here, the porous Mn doped g-C3N4 photocatalyst was synthesized by the calcination-refluxing method. The as-prepared g-C3N4 exhibits the high activity of photocatalytic degradation under visible light irradiation ( > 400nm) in the mixed system of Cr(VI) and organic pollutants. Especially, the photocatalytic activity of Cr(VI) reduction was increased from 9.5% to 76.5%, while that of Rhodamine B(RhB) degradation was enhanced from 15.3% to 88.9% after 60min irradiation. The porous Mn doped g-C3N4 still keeps the high degradation efficiency of mixed pollutants in the 7th running. Based on the computational modeling, the Mn doping and carboxyl modification affect the atomic arrangement and molecular orbital distribution of the g-C3N4 semiconductor, leading to the enhancement of photo-induced carrier separation. Additionally, the active oxygen species and intermediates in the photoreaction process were discovered by ESR measurement and UV-vis test. The RhB degradation in synergistic photocatalysis not only inhibits the reverse reaction of Cr(VI) reduction, but also validly supply the photogenerated electrons by the photosensitization effect. This work may be useful for rationally designing photocatalysts and providing illuminating insights into the photocatalytic mechanism.