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Characterizing and predicting the response of terrestrial ecosystems to global change is part of the fundamental challenges of contemporary ecology and ecological conservation. The assessment of climate change impact on forest ecosystems has rarely used a multi-index fusion method for quantitative evaluation. We used forest distribution, net primary productivity, and vegetation coverage to establish an assessment model of the impact of climate change on forest ecosystems. We analyzed the change characteristics of these indicators in the Heilongjiang Province of China. Our results indicate the following: (1) from 2001 to 2019, the forest area in Heilongjiang Province ranged from 234,000 to 246,000 km2. The forest net primary productivity (NPP) ranged from 4.40 to 5.55 MgC·ha-1·yr-1, and the vegetation coverage ranged from 42.42% to 67.64%. The forest NPP and the vegetation coverage showed a significant upward trend. (2) The values of forest ecological roles were significantly positively correlated with the climatic potential. (3) The contribution rate of climate change to forest ecosystem change was negatively correlated with forest coverage, which varied from 4.79% to 18.07% in different regions (cities) of the province. Study Implications: Assessing the influence of climate on forest ecosystems comprehensively and accurately before the government prepares ecological measures is necessary. However, the responses of vegetation coverage and net primary productivity to climate change may not be consistent, so climate studies that consider forest ecosystem change trends by a single indicator may have confounding results. We established a model for evaluating the impact of climate change on forest ecosystems to solve this problem. This knowledge may provide a reference for the response, adaptation, and vulnerability assessment of forest ecosystems to climate change.

Introduction Neuromuscular blockade suppresses transcranial electrical motor evoked potential (TceMEP) amplitude and is usually avoided during TceMEP monitoring. In this randomized controlled trial, we investigated whether rocuronium-induced suppression of TceMEP amplitude could be reversed by sugammadex in patients undergoing spine surgery. Methods Seventy-six patients undergoing spinal surgery were randomly allocated into sugammadex and control groups. In the sugammadex group, a rocuronium infusion was titrated to maintain moderate neuromuscular blockade (2 twitches on train-of-four) until dural opening when the rocuronium infusion was discontinued and 2 mg/kg sugammadex administered. In the control group, no neuromuscular blockade was administered after induction of anesthesia. The primary outcome was a comparison between sugammadex and control groups of mean TceMEP amplitudes in the abductor pollicis brevis muscles of both upper extremities 5 minutes after dural. Secondary outcomes included TceMEP amplitudes at 10, 20, 30, and 60 minutes after dural opening. Results Sixty-six patients were included in the analysis. TceMEP amplitudes were significantly greater in the sugammadex group (629 μV, interquartile range: 987 μV) than in the control group (502 μV, interquartile range: 577 μV; P=0.033) at 5 minutes after dural opening. TceMEP amplitudes were also greater in the sugammadex group at 10 minutes (P=0.0010), 20 minutes (P=0.003), 30 minutes (P=0.001), and 60 minutes (P=0.003) after dural opening. Conclusions Moderate neuromuscular blockade induced by continuous infusion of rocuronium was effectively reversed by sugammadex. This suggests that sugammadex could be used to enhance TceMEP waveform monitoring during spine surgery requiring muscle relaxation.

InP shows a very high efficiency for solar light to electricity conversion in solar cell and may present an expectation property in photocatalytic hydrogen evolution. However, it suffers serious corrosion in water dispersion. In this paper, it is demonstrated that the stability and activity of the InP-based catalyst are effectively enhanced by applying an anti-corrosion SnO layer and In(OH)3 transition layer, which reduces the crystal mismatch between SnO and InP and increases charge transfer. The obtained Pt/SnO/In(OH)3/InP exhibits a hydrogen production rate of 144.42 µmol/g in 3 h under visible light illumination in multi-cycle tests without remarkable decay, 123 times higher than that of naked In(OH)3/InP without any electron donor under visible irradiation.

The superhydrophobic ZnO@stearic acid (ZnO@STA) nanoarrays have been prepared and synchronously introduced plentiful oxygen vacancies by using hydrothermal method on the Zn substrate. After UV–Visible light irradiation, the superhydrophobic ZnO@STA surface is transformed into the superhydrophilic surface, which is mainly attributed to the excitation of electron-hole pairs and reaction with the adsorbed O2 and H2O from air to form hydroxyl radicals on the ZnO@STA surface, and not photodegradation of STA. Also, the introduced defect energy levels of oxygen vacancies make more electron-hole pairs excited by visible light. Continuing to further heat the ZnO@STA surface, the photoinduced hydroxyl radicals are desorbed from the ZnO@STA surface, making the photoinduced superhydrophilic surface revert to the original superhydrophobic surface. And the reverse wetting transition can be accelerated through the increase of heating temperature. Moreover, the ZnO@STA nanorod array surface also exhibits excellent cycle stability of reversible switch between superhydrophobicity and superhydrophilicity.

Previous studies showed physical activity had benefits for older adults’ life satisfaction, but the mechanism was unclear. This study aimed to investigate whether older adults with more physical activity had better functional fitness and life satisfaction, and whether functional fitness mediated the relationship between physical activity and life satisfaction. A cross-sectional study design was employed, and 623 older adults (73.71 ± 5.91 years) were recruited. Physical activity, functional fitness, life satisfaction, and demographic characteristics were collected. Compared with older adults with low physical activity, those with high (B = 0.41, p = 0.025) and moderate (B = 0.40, p = 0.041) physical activity had better life satisfaction; those with high physical activity had better lower limb muscle strength (B = 1.71, p = 0.001), upper (B = 2.91, p = 0.032) and lower (B = 3.12, p = 0.006) limb flexibility, cardiorespiratory endurance (B = 6.65, p = 0.008), and dynamic balance ability (B = −1.12, p < 0.001). Functional fitness did not mediate the relationship between physical activity and life satisfaction. Promoting physical activity may be useful for increasing older adults’ functional fitness and life satisfaction, but the effects on functional fitness only occurred at a high level of physical activity, and the effect of physical activity on life satisfaction was not mediated by functional fitness.

Multifunctional electronic devices that possess synchronously multiphysical characteristics are in great demand to be widely used in various complex conditions. Herein, for the most promising light...

The exposure of more stable {001} facets to micro/nanostructure surface and heterojunction are effective measures to enhance the photocatalysis activity. A new mixed-crystal nanostructure of K3TiOF5/TiO2 with dominant {001} facets was well designed and successfully fabricated by a facile hydrothermal method. The introduction of K3TiOF5 stimulates the formation of stable and dominant {001} facets, and the mixed-crystal nanostructure improves the charge separation under light irradiation. Then, it is used to photodegradate anionic dyes, the photodegradation reaction rate of such K3TiOF5/TiO2 reaches up to 6.0108 h-1, which is 15.5 and 2.2 times higher than that of pure TiO2 nanospheres (0.3876 h-1) and P25 (2.6718 h-1), respectively. And more than 98% of MO are removed within 40 min. Its better photocatalysis activity would be mainly attributed to the efficient charge separation in such mixed-crystal nanostructure and ingenious morphology for giving more photocatalytic active-sites.

A new sphere-like nano-heterostructure of Cu3SnS4@C (CTS@C) was well designed and fabricated by two-step hydrothermal route, which is ideally suited for synergistic physical adsorption and photodegradation of anionic dye. Compared to the pure C or CTS nanospheres, CTS@C nano-heterostructure has smaller surface area but exhibits excellent performance. It possesses high adsorption efficiency of 97.04% for removal of methyl orange (MO) at pH 5.5. And also, the superior synergistic adsorption and photodegradation performance makes it exhibit 99.38% degradation efficiency within 210 min at pH 7.5, which is about 1.8 times higher than that of simplex adsorption (56.23%). These might be attributed to the higher light harvesting, effective charge separation, lower charge-transfer resistance and high photocurrent response properties of CTS@C nanostructures. Moreover, the CTS@C nano-heterostructured photocatalyst can effectively avoid surface passivation during the process of synergistic adsorption and photodegradation, and be easily regenerated from the reaction system for recycling, suggesting a promising candidates for synergistic adsorption and photocatalysis applications.

A simple hydrothermal method is successfully used to prepare the La2O3 film, and the accurate control of its surface structure is realized through the hydrothermal temperature and time from the sparsely dispersed compact microspheres to closely packed microsphere film, then from the hierarchical structure of the sparsely dispersed compact and flower-like microspheres accompanied with the discrete vertical-standing nanopetals to the hierarchical structure constituted by the closely packed compact microspheres and dense vertical-standing nanopetals. The XRD analysis shows the prepared film is mainly made of hexagonal La2O3 accompanied with some impurities of La(OH)2NO3, La(OH)3 and La2TiO5. Valuably, the prepared La2O3 film has high capacitance which can be modulated by surface structure, and achieves the maximum when the surface structure is hierarchical structure constituted by the closely packed compact microspheres and vertical-standing nanopetals. Eventually, the high capacitance leads to the electrowetting-on-dielectric (EWOD) responses with low voltage actuation below 8 V and wide contact angle modulation range of about 131°. The works are very beneficial to the design and preparation of supercapacitor and EWOD devices with high performance.

In this paper, we study the asymptotic stability of the monotone decreasing kink profile solitary wave solutions of the generalized Gardner equation with dissipative term. Firstly, we obtain the estimation of the first-order and second-order derivatives for monotone decreasing kink profile solitary wave solutions, then by using anti-derivative strategy, with the help of prior estimate and Young inequality, we overcome the difficulties caused by two higher-order nonlinear terms of the equation in the estimation, and prove the asymptotic stability of monotone decreasing kink profile solitary wave solution in the sense of [Formula: see text] norm.

In electrochemical metallization memristor, the performance of resistive switching (RS) is influenced by the forming and fusing of conductive filaments within the dielectric layer. However, the growth of filaments, mostly, is unpredictable and uncontrollable. For this reason, to optimize ions migration paths in the dielectric layer itself in the Al/Cu

Characterizing and predicting the response of terrestrial ecosystems to global change is one of the key challenges of contemporary ecology and ecological conservation. The impact of climate change on forest ecosystem has been widely studied, but it rarely uses method of multi-index fusion for quantitative evaluation. In this study, forest ecosystem in Heilongjiang Province was investigated. Based on remote sensing, meteorological observation, ground survey, geographic information, MAXENT model, CASA model, carbon sequestration potential model of Zhou Guangsheng-Zhang Xinshi, pixel dichotomy model and Savitzky Golay Filter model were used. On this basis, we analysed the change characteristics of forest distribution, net primary productivity and vegetation coverage. We also established a model for evaluating the impact of forest ecosystem change on climate, and made a quantitative assessment of the impact on climate. Our results indicate the following: (1) From 2001 to 2019, the forest area in Heilongjiang Province ranged from 2.34 × 105 to 2.46 × 105 km2, the forest NPP ranged from 40.48 to 555.32 gC/m2/a, and the vegetation coverage ranged from 42.42% to 67.64%, both of which showed a significant upward trend; (2) The values of forest ecological role were significantly positively correlated with the climatic potential; (3) The results of climate impact assessment of forest ecosystem change showed the contribution rate of climate change to forest ecosystem change was negatively correlated with forest coverage, which varied from 4.79% to 18.07% in different regions (cities) of the province. This study contribute to improving evaluating influence of climate change on forest ecosystem.

As a carrier of environmental pollutants, microplastics have received wide concerns in recent years. However, the direct and indirect effects of the coexistence of polystyrene particles (PS) and pollutants on vegetables are still unclear. Here, the combined effects of 0.25, 0.50, 1.0 mg·mL微塑料作为环境污染物的载体,近年来受到广泛关注,而人们对聚苯乙烯颗粒(PS)与污染物共存对蔬菜的直接和间接影响认识有限。本研究采用水培方法分析了0.25、0.50、1.0 mg·mL

To improve the spreading ability of a water droplet on a structured surface, the tip effect is proposed to enhance the local electric field near the cone tip under the application of voltage, and further increases the horizontal force on the water droplet. Thus, a vertical-standing ZnO nanocone array was designed and prepared on a Zn substrate by a simple one-step hydrothermal method, and the cone tip was modulated from a spiculate nanocone to nanorod through adjusting the hydrothermal time and temperature. Experimentally, the electrowetting-on-dielectric (EWOD) responses of the prepared ZnO nanocone array were measured, and the contact angle (CA) modulation under the application of voltage below 30 V reached a value of 89° due to the synergistic effects of the tip effect and electric adsorption. Theoretically, the electric field distribution in the nanocone array was simulated by using the finite element method, and the nanocone array was optimized to enhance the local electric field near the nanocone tip and to suppress the wetting transition from the Cassie state to the Wenzel state. The work is very beneficial to the achievement of a spontaneous switchable EWOD with large CA modulation on the structured surface.

The slow photon effect can significantly increase the effective optical path length of light and thereby enhance the interaction of light with matter, which would be realized by light propagating at the edges of the photonic band gap (PBG) in photonic crystals (PCs). In this paper, a novel anodic oxidation method with effective voltage-pulse compensation was developed to prepare one-dimensional titania nanotube photonic crystals (1D TiO2 NT PCs) with a high quality of PBG, which could be continuously adjusted and precisely tailored just by modulating the anodization parameters. With the increase of low voltage (Lv) duration, the precise blue shift of the PBG of 1D TiO2 NT PCs was recorded. Through the precise tailoring of PBG in bandgap engineering, the edges of the PBG could be designed and purposely tuned to overlap with the electronic band gap range of the TiO2 material, and the as-prepared 1D TiO2 NT PCs were used as a photocatalyst to degrade methyl orange (MO) molecules due to the enhanced slow photon effect and scattering effect in their highly ordered channel structures. Meanwhile, strategies to enhance the slow photon effect at the edge of the PBG were discussed and evaluated in detail according to our experimental and simulated results. This study would provide a new guide to taking advantage of the slow photon effect to enhance the photocatalytic activities, photoluminescence, and performances of other optoelectronic devices.

Designing adsorbents possessing high-efficient and selective adsorption performance is valuable for water pollution control, yet challengeable. Herein, a new N,N-dimethylformamide (DMF)-hydrothermal strategy was introduced to treat amorphous carbon nanospheres (CNPs) to make it possess a pH-sensitive and high selective adsorption behavior for organic dye. Excitingly, the surface electrical behavior of DMF-CNPs and CNPs are entirely different at pH 5.0, and thus in striking contrast to CNPs, DMF-CNPs exhibits a rapid removal of 70 mg L−1 cationic rhodamine B (at least 99% within 10 min), and also a pH-sensitive adsorption with a maximum adsorbability of 63.85 mg g−1 at pH 9.0 and a minimum value of 32.99 mg g−1 at pH 3.0. The DMF-CNPs's adsorption mechanism could be well explained the pseudo-second-order kinetic model and better fitted the Langmuir isotherm model with a high adsorption capacity of 56.56 mg g−1 at pH 6.5. The significantly improved adsorption performance of DMF-CNPs could be mainly ascribed to its doubled specific surface area, more positive charged active sites of oxygen-containing functional groups available for synergistic adsorption.

In this study, a new magnetically separable Cu2ZnSnS4/ZnFe2O4 p-n heterostructured nano-photocatalyst was first prepared by a facile two-step hydrothermal method. The characterizations of morphology and microstructure revealed that the p-type Cu2ZnSnS4 (CZTS) nanosheets were successfully assembled on the surface of ZnFe2O4 (ZFO) nanospheres, forming a CZTS/ZFO p-n heterostructures. A series of test results showed that this p-n heterostructures could not only efficiently expand spectral response and promote photoinduced charges separation, but also increase the specific surface areas for photocatalytic and photo-Fenton reactions. All these factors resulted in the p-n heterostructured CZTS/ZFO nano-photocatalyst plus H2O2 having a significantly enhanced photocatalytic activity for degradation of methyl orange (MO) at visible light irradiation, compared to the pure ZFO, the removal efficiency available reached up to 91% within120 min. These outstanding performances should be ascribed to the synergistic enhancement effects of the CZTS/ZFO p-n heterostructure combining with photo-Fenton mechanism, which could be confirmed by exploring the dominant effects of radical scavengers and the yield of hydroxyl radicals (·OH) on the surface of the p-n heterostructured nano-photocatalyst with and without contribution of photo-Fenton reaction for the MO removal. Furthermore, the CZTS/ZFO p-n heterostructured nano-photocatalyst exhibited remarkably stable and easy separated performances, suggesting a promising application for the photo-oxidative degradation of organic contaminants.

The composite structures of tightly embedding the rare-earth oxide La2O3 nanoparticles into TiO2 film are designed and have been successfully prepared by using the sol-gel and spin-coating method. Appearance of a large amount of nano-cracks on the La2O3@TiO2 composite film surface supplies a textured surface to study the effect of nanostructured surface on the electrowetting on dielectric (EWOD) performance. The characterizations of chemical composition and crystal phase structure indicate the La2O3 nanoparticles with polycrystalline nature have been grown and distribute uniformly in TiO2 film. Valuably, plenty of intimate contact heterogeneous La2O3/TiO2 interfaces are formed, and supply an ideal space for charge accumulation and electric energy storage. All data of EWOD response test show the applied superlow voltage can induce a large contact angle (CA) change, but the breakdown voltage is still high. The EWOD response does not agree with the well-known Young-Lippmann equation, especially obvious in low voltage range. Moreover, the optimal parameters of layer number of 8 and La3+ doping concentration of 0.9% are obtained to enhance EWOD response for superlow applied voltage and the lower saturation CA. Detailed investigations and analysis reveal that the electric absorption has important roles on EWOD response under superlow applied voltage for the nanostructured surface. Furtherly, the space charge polarization theory is proposed to illustrate the enhancement of EWOD performance. When the voltage is applied, plenty of charges would be accumulated on the heterogeneous La2O3/TiO2 interfaces and the space charge polarization is formed, this significantly heightens polarizability of the La2O3@TiO2 composite film, and further increases their effective dielectric constant and improves EWOD performance. But the electric absorption of water on the nanostructured surface causes the inconsistency of EWOD response with the tested and calculated capacitance. The present study shows a new insight to design and fabricate structured dielectric for the solution of EWOD difficulties.

Introduction Assisted reproductive technology has been proposed for women with infertility. Moreover, in vitro fertilization (IVF) cycles are increasing. Factors contributing to successful pregnancy have been widely explored. In this study, we used machine learning algorithms to construct prediction models for clinical pregnancies in IVF. Materials and methods A total of 24,730 patients entered IVF and intracytoplasmic sperm injection cycles with clinical pregnancy outcomes at Taipei Medical University Hospital. Data used included patient characteristics and treatment. We used machine learning methods to develop prediction models for clinical pregnancy and explored how each variable affects the outcome of interest using partial dependence plots. Results Experimental results showed that the random forest algorithm outperforms logistic regression in terms of areas under the receiver operating characteristics curve. The ovarian stimulation protocol is the most important factor affecting pregnancy outcomes. Long and ultra-long protocols have shown positive effects on clinical pregnancy among all protocols. Furthermore, total frozen and transferred embryos are positive for a clinical pregnancy, but female age and duration of infertility have negative effects on clinical pregnancy. Conclusion Our findings show the importance of variables and propensity of each variable by random forest algorithm for clinical pregnancy in the assisted reproductive technology cycle. This study provides a ranking of variables affecting clinical pregnancy and explores the effects of each treatment on successful pregnancy. Our study has the potential to help clinicians evaluate the success of IVF in patients.

Facial recognition has attracted more and more attention since the rapid growth of artificial intelligence (AI) techniques in recent years. However, most of the related works about facial reconstruction and recognition are mainly based on big data collection and image deep learning related algorithms. The data driven based AI approaches inevitably increase the computational complexity of CPU and usually highly count on GPU capacity. One of the typical issues of RGB-based facial recognition is its applicability in low light or dark environments. To solve this problem, this paper presents an effective procedure for facial reconstruction as well as facial recognition via using a depth sensor. For each testing candidate, the depth camera acquires a multi-view of its 3D point clouds. The point cloud sets are stitched for 3D model reconstruction by using the iterative closest point (ICP). Then, a segmentation procedure is designed to separate the model set into a body part and head part. Based on the segmented 3D face point clouds, certain facial features are then extracted for recognition scoring. Taking a single shot from the depth sensor, the point cloud data is going to register with other 3D face models to determine which is the best candidate the data belongs to. By using the proposed feature-based 3D facial similarity score algorithm, which composes of normal, curvature, and registration similarities between different point clouds, the person can be labeled correctly even in a dark environment. The proposed method is suitable for smart devices such as smart phones and smart pads with tiny depth camera equipped. Experiments with real-world data show that the proposed method is able to reconstruct denser models and achieve point cloud-based 3D face recognition.

Physical activity has benefits on physical and psychological health. The aims of this study were to investigate (1) the relationships between physical activity and life satisfaction and happiness in young, middle-aged, and older adults while controlling for demographic characteristics, and (2) the relationships between age and life satisfaction and happiness for different physical activity levels. A total of 2345 healthy adults were recruited. Demographic characteristic, physical activity, life satisfaction, and happiness were collected. Participants were divided into young, middle-aged, and older adult groups based on age, and physical activity was categorized as high, moderate, and low. After controlling for demographic characteristics, participants with high and moderate activity levels had significantly higher life satisfaction and happiness than those with a low activity level across the total population and the three age groups. Age squared was a significant predictor of a positive curvilinear between age and life satisfaction and happiness. Physical activity was significantly related to life satisfaction and happiness in young, middle-aged, and older adults. In addition, life satisfaction and happiness increased with increasing age. The results support the promotion of physical activity.

A new designed counter electrode of oriented NiS nanoflower arrays for dye-sensitized solar cells has successfully achieved by vulcanizing reaction from electrochemical deposited Ni nanoflowers on FTO substrate. For its large specific surface area and beneficial effect of electron transfer along the vertical sheet petals, NiS nanoflower arrays possess both a higher electrocatalytic activity for I3− reduction and a relatively better electrochemical stability, having the power conversion efficiency of 9.49%, which is 1.2 times higher than Pt (7.88%). Such physical design of oriented nanoflower arrays can be expected to lead a direction for facile constructing high efficient chalcogenides cathode materials.

In electrochemical metallization memristor, the performance of resistive switching (RS) is influenced by the forming and fusing of conductive filaments within the dielectric layer. However, the growth of filaments, mostly, is unpredictable and uncontrollable. For this reason, to optimize ions migration paths in the dielectric layer itself in the Al/Cu x S/Cu structure, uniform Cu x S nanosheets films have been synthesized using anodization for various time spans. And the Al/Cu x S/Cu devices show a low operating voltage of less than 0.3 V and stable RS performance. At the same time, a reversible negative differential resistance (NDR) behavior is also demonstrated. And then, the mechanism of repeatable coexistence of RS effect and NDR phenomenon is investigated exhaustively. Analyses suggest that the combined physical model of space-charge limited conduction mechanism and conductive filaments bias-induced migration of Cu ions within the Cu x S dielectric layer is responsible for the RS operation, meanwhile, a Schottky barrier caused by copper vacancy at the Cu x S/Cu interface is demonstrated to explain the NDR phenomenon. This work will develop a new way to optimize the performance of non-volatile memory with multiple physical attributes in the future.

An effective one-step solvothermal process is developed to fabricate La2O3 film on Ti substrate at 130 °C. The surface morphology and roughness are controlled from urchin-like nanosphere to dense film by the reaction duration. The as-prepared La2O3 film has low surface free energy and a large initial contact angle (CA), about 120°. Due to the uniform distribution of the urchin-like nanosphere on the surface, the water droplet starts to be adsorbed into the interspace of film surface, and the wetting state gradually transforms from Cassie to Wenzel state as soon as the low voltage less than 1 V is applied. Obviously, the DC EWOD response with superlow voltage can be realized, and large CA modulation about 58° is also acquired.

The three-dimensional (3-D) copper sulfide nanowalls with sharp edges were successfully prepared by one-step anodization method. An interesting finding was that the morphology and microstructure of 3-D copper sulfide nanowalls can be regulated and optimized by abjusting the anodization time, and the corresponding field emission (FE) characteristics were significantly improved. The value of turn-on field can be dramatically reduced from 11.84 to 2.84 V/μm and the field enhancement factor up to 19899. Besides, the optimal 3-D copper sulfide nanowalls showed a long-term thermal stability and better conductivity. Preliminary researches indicate that as a promising field emitter, the 3-D copper sulfide nanowalls have potential applications in the field of vacuum micro- or nano-electronic devices.

A novel high efficient p-n heterostructure photocatalyst is well designed and firstly realized on coupling electrospun TiO2 anatase/rutile mixed-crystal nanorods (T-A/R-NRs) and p-type ternary Cu3SnS4 (CTS), which is a hot photosensitive material in photovoltaics but rarely attracted in photocatalysis. Such configured CTS@T-A/R-NRs shows 2.02 eV band-gap and are demonstrated to be more efficient in photocatalytic degradation. The optimized CTS@T-A/R-NRs with 24 h hydrothermal reaction possesses a superior degradation rate of 1.3980 h−1, which is 2.5 and 4.3 times than T-A/R-NRs (0.5490 h−1) and CTS (0.3240 h−1). It is mainly attributed to the better morphology for high light-harvesting, the established built-in electric field at p-n interfaces and special anatase/rutile mixed-crystal structure of TiO2 for efficient separation of photogenerated charges. The study indicates a promising strategy in designing potential nanostructures to simultaneously achieve high efficient photocatalytic degradation and photovoltaic conversion.

A novel p-n heterostructural film photocatalyst of oriented NiS/TiO2 nanosheet arrays were designed and successfully fabricated via a simple two-step hydrothermal process, and its photodegradation activities of methyl orange (MO) were detailedly investigated. Combining p-type NiS nanoparticles with n-type TiO2 nanosheets to construct distributed p-n heterojunctions, the absorption edge of NiS/TiO2 red-shifted to about 471 nm and its photoresponse in visible range significantly enhanced. Compared with pure TiO2 nanosheet arrays (NSAs), the assembled NiS/TiO2 p-n heterostructural arrays with 0.003 M NiS in hydrothermal precursor solution showed an optimal degradation rate of k = 0.7368 h−1 for MO, achieving 76.3% photocatalytic efficiency within 120 min, which is about 2.34 times higher than that of pure TiO2 nanosheet arrays (k = 0.3144 h−1). Such enhanced photocatalytic activities should be attributed to both the high efficiency of photogenerated charge separation by the built-in electric field at interfaces of NiS-TiO2 and the oriented thin nanosheet structures for smoothly charge transportation for redox reactions at surfaces of NiS/TiO2.