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[Display omitted] • Utilizing siloxane surfactants enable the top surface reconstruction of CsPbI 3. • A self-assembled siloxane ligand layer is formed on the surface of CsPbI 3. • The phase transition of CsPbI 3 can be efficiently suppressed. • The surface and interfacial defects in the perovskite are well passivated. • A champion efficiency of 21.42 % is achieved for CsPbI 3 solar cell. All-inorganic perovskite is a promising candidate for solar cell applications. However, a significant challenge lies in its poor phase stability to environmental moisture. To address this problem, we develop a strategy for in-situ reconstruction of the CsPbI 3 surface using siloxane surfactants such as 3-aminopropyltriethoxysilane (APTES) and 3-aminopropyltrimethoxysilane (APTMS), which both demonstrate multifunctional roles in surface engineering. The siloxanes undergo air-induced hydrolysis, leading to the formation of Si-O-Si networks. Additionally, the –NH 2 convert to –NH 3 +, enabling interaction with the I− ions on the surface of CsPbI 3. This facilitates the formation of a self-assembled siloxane cross-linked ligand layer, which offers extra function for providing water and oxygen shielding, consequently stabilizing the surface of CsPbI 3. Furthermore, the siloxane surfactants can passivate uncoordinated Pb2+ ions, resulting in a reduction of non-radiative recombination at the interface, thereby significantly augmenting device performance and stability. Following research comparisons, APTES with longer alkyl chains displays superior performance. As a result, with the APTES passivation, the PCE is increased from 19.01 % to 21.42 %, which is one of the highest PCE devices in pure CsPbI 3 PSCs reported so far. Meanwhile, the devices treated with APTES show superior moisture stability over those without APTES, especially in the absence of encapsulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heterometallic organic cages with tunable metal ratios were constructed. • The heterometallic organic cages exhibited remarkable cascade antioxidant nanozyme activities. • The synergistically enhanced enzyme activity was elucidated through experiments and theoretical calculations. • The cascade nanozyme can effectively alleviate renal ischemia–reperfusion injury. The regulation of reactive oxygen species (ROS) by antioxidant enzymes plays a crucial role in managing tissue ischemia–reperfusion (I/R) injury. However, the imprecise structures of most developed nanozymes pose significant challenges for their structure–activity interpretation and clinical translation. Additionally, the monotonous enzyme-like activity exhibited by most nanozymes also restricts their efficacy. In this study, we have developed well-defined cascade nanozymes based on metal organic cages (MOCs) to effectively eliminate excessive ROS in the context of renal I/R injury. By integrating nickel and cobalt within the MOC, we obtained heterometallic organic cage (HMOC) nanozymes with adjustable metal ratios. The incorporation of these two metals into a single MOC nanozyme not only expands its catalytic activity but also enables it to facilitate complex antioxidant reactions more effectively than traditional multi-step processes. The performance of HMOC cascade nanozymes, which mimic the cascade activities of superoxide dismutase (SOD) and catalase (CAT), in converting superoxide anion radicals (O 2 –) into oxygen and water is synergistically enhanced by the heterometallic interactions within a single metal cluster in the HMOC structure. Through optimization of the metal ratio within HMOC-2, both in vitro and in vivo experiments demonstrate that its ROS-scavenging capacity surpasses that of other groups significantly, thereby effectively alleviating renal I/R injury. This study not only presents well-defined enzyme-like cascade systems but also highlights their promising therapeutic potential for treating renal I/R injury. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Z-type Fe 2 O 3 /MoO 3 heterojunction was synthesized for the PEF-like system. • Simultaneously proposed 1O 2 generation and CIP degradation. • Fe 2 O 3 /MoO 3 could generate and activate H 2 O 2 in the PEF-like system. • ·O 2 − and H 2 O 2 were sources of 1O 2 in the FMO-1-PEF-like system. Singlet oxygen (1O 2), a typical reactive oxygen species (ROS) with selective oxidation properties, holds great application prospects in water environment treatment. However, the 1O 2 generation mechanism in photo-electro-Fenton-like (PEF-like) system for water purification is still unclear. In this study, we developed a Fe 2 O 3 /MoO 3 (abbreviated as FMO-x) Z-type heterojunction and achieved efficient degradation of ciprofloxacin (CIP). In-situ irradiated XPS, EPR, and DFT calculations confirmed that the coupling interface of FMO-1 Z-type heterojunction effectively enhanced the charge separation and transfer process, thus generating various ROS (1O 2 , ·O 2 −, ·OH and H 2 O 2). In the FMO-1-PEF-like system, H 2 O 2 was generated in-situ through 2e− ORR. In addition, ROS quantitative experiments showed that the yield of 1O 2 , ·O 2 − and ·OH was 29.76, 92.54 and 1.09 μmol·L−1 in 60 min, respectively. EPR and XPS results indicated two potential routes for the 1O 2 generation: the reaction between ·O 2 − and Fe3+ and between ·O 2 − and H 2 O 2. In the FMO-1-PEF-like system, the removal rate of CIP was 97.10 % in 60 min, and the kinetic constant was 0.0626 min−1, which was 1.32 and 1.55 times higher than that of Fe 2 O 3 and MoO 3. This work developed a method using Fe 2 O 3 /MoO 3 Z-type heterojunction to understand the mechanism of the 1O 2 generation in the PEF-like system. [ABSTRACT FROM AUTHOR]

[Display omitted] • An in-situ dynamic experiment on a 320 cm2 PEMFC is conducted. • An in-situ monitoring method and a voltage loss decoupling method is utilized. • The mechanisms of the voltage undershoot of fuel cells are thoroughly studied. • The in-plane heterogeneity of the voltage undershoot in large area PEMFC is analyzed. • Suggestions for improving the dynamic performance of fuel cells are proposed. The voltage undershoot is one of the main dynamic problems of proton exchange membrane fuel cells (PEMFCs) under dynamic loadings. However, its mechanisms remain poorly understood due to its complex and coupled influencing factors. Besides, PEMFCs with a large active area are more prone to local dynamic failures for their pronounced in-plane (I-P) heterogeneity, while few studies have focused on the I-P heterogeneity of the dynamic response of large-area fuel cells. In this work, the mechanisms and the I-P heterogeneity of the voltage undershoot of a 320 cm2 PEMFC are thoroughly studied based on an in-situ monitoring method and a voltage loss decoupling method. Results show that the voltage overshoot is primarily driven by the ohmic loss (OL) overshoot and the concentration polarization (CP) overshoot. Results also prove that the OL overshoot is mainly caused by the instantaneous water shortage in the proton exchange membrane (PEM) which depends on the initial water content in the PEM. Besides, the CP overshoot is due to the instantaneous reactant shortage at the catalyst, and it is much sensitive to the change in the oxygen diffusion coefficient of the ionomer caused by the change in its water content. Meanwhile, both OL overshoot and CP overshoot demonstrate significant I-P heterogeneities under poor dynamic operating conditions, especially in cases of high load step and low inlet air humidity. Finally, the influences of operating conditions on the voltage undershoot and its I-P heterogeneity are discussed, and suggestions for improving the dynamic performance of PEMFCs are proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Modified ferric sludge with high aluminate cement and copper oxide as an oxygen carrier. • Improved stability and reactivity of OC observed with addition of CuO. • FSCuO10 achieved stable performance of > 92 % across 50 cycles. • FSCuO10 showed minimal agglomeration and attrition of < 4 % after 50 cycles. • FSCuO10 achieved stable performance throughout 300 cycles. This study focuses on enhancing the performance of water treatment sludge as an oxygen carrier (OC) for chemical looping combustion (CLC) of municipal solid waste (MSW) syngas. High aluminate cement was introduced to augment the OC's mechanical strength, concurrently preventing inter-particulate agglomeration, resulting in a commendable and low agglomeration rate of 3.44% after 50 cycles. The inclusion of CuO proves to be instrumental in boosting the OC's reactivity, mitigating the loss of active components due to the addition of cement support. Notably, FSCuO10 (Ferric sludge with 10% CuO addition) demonstrates over 92% CO efficiency throughout 50 cycles, affirming the success of the dual modification of FS. The investigation also delves into comprehending the reduction process, agglomeration pathways, and the impact of varied CuO percentages has on OC performance. Extensive characterizations were conducted to elucidate OC transformations and their consequential effects on reactivity, physical characteristics, and overall performance. A noteworthy observation includes the outward migration of iron and copper during CLC, contributing to the stabilization of reactivity. In summary, the modifications implemented on FS, yield an improved OC for CLC purposes, maintaining its novelty and cost-effectiveness. The novelty stems from the interactions between CuO and FS, leading to improved reactivity and stability, as well as the extended CLC, which demonstrates the longevity of the OCs. This research contributes to the circularity of waste-derived products by effectively repurposing water treatment sludge and improving sustainable waste management practices. [ABSTRACT FROM AUTHOR]

• A sub-100 nm perovskite-based fluorescent probe modified with the survivin antibody was developed. • Polyvinyl pyrrolidone (PVP) coated perovskite crystals can keep the probe with great fluorescence intensity and resistance of water and oxygen. • The survivin protein can be an ideal fluorescence target for rapid diagnosis of colorectal cancer. Due to non-specific signs in the early stage of colorectal cancers, most patients result in a low early diagnosis rate. Survivin protein is upregulated in many malignant tumors, making it an ideal diagnostic and therapeutic target for colorectal cancers. However, the survivin protein is located in the cell nucleus, which needs the probe to penetrate the complex nuclear membrane structure for targeting and recognizing. Here, we have developed a sub-100 nm perovskite-based fluorescent probe modified with the survivin antibody, which can freely target survivin protein through the nuclear membrane. Polyvinyl pyrrolidone (PVP) coated perovskite crystals are obtained by the supersaturated crystallization, which keep the probe with great fluorescence intensity and resistance of water and oxygen. We have established colorectal cancer cell lines and colorectal cancer tissues to test the feasibility and efficacy of the probe. After investigating the fluorescence intensity values of 20 probing samples, the average fluorescence intensity of colorectal cancer sections is 8.7 times higher than that of paracancerous tissues. Our work demonstrates that the survivin can be an ideal fluorescence target for rapid diagnosis of colorectal cancer, which also provides a research foundation for fluorescence-guided surgery and nano-therapy for targeting the survivin protein. [ABSTRACT FROM AUTHOR]

[Display omitted] • Utilizing siloxane surfactants enable the top surface reconstruction of CsPbI 3. • A self-assembled siloxane ligand layer is formed on the surface of CsPbI 3. • The phase transition of CsPbI 3 can be efficiently suppressed. • The surface and interfacial defects in the perovskite are well passivated. • A champion efficiency of 21.42 % is achieved for CsPbI 3 solar cell. All-inorganic perovskite is a promising candidate for solar cell applications. However, a significant challenge lies in its poor phase stability to environmental moisture. To address this problem, we develop a strategy for in-situ reconstruction of the CsPbI 3 surface using siloxane surfactants such as 3-aminopropyltriethoxysilane (APTES) and 3-aminopropyltrimethoxysilane (APTMS), which both demonstrate multifunctional roles in surface engineering. The siloxanes undergo air-induced hydrolysis, leading to the formation of Si-O-Si networks. Additionally, the –NH 2 convert to –NH 3 +, enabling interaction with the I− ions on the surface of CsPbI 3. This facilitates the formation of a self-assembled siloxane cross-linked ligand layer, which offers extra function for providing water and oxygen shielding, consequently stabilizing the surface of CsPbI 3. Furthermore, the siloxane surfactants can passivate uncoordinated Pb2+ ions, resulting in a reduction of non-radiative recombination at the interface, thereby significantly augmenting device performance and stability. Following research comparisons, APTES with longer alkyl chains displays superior performance. As a result, with the APTES passivation, the PCE is increased from 19.01 % to 21.42 %, which is one of the highest PCE devices in pure CsPbI 3 PSCs reported so far. Meanwhile, the devices treated with APTES show superior moisture stability over those without APTES, especially in the absence of encapsulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Heterometallic organic cages with tunable metal ratios were constructed. • The heterometallic organic cages exhibited remarkable cascade antioxidant nanozyme activities. • The synergistically enhanced enzyme activity was elucidated through experiments and theoretical calculations. • The cascade nanozyme can effectively alleviate renal ischemia–reperfusion injury. The regulation of reactive oxygen species (ROS) by antioxidant enzymes plays a crucial role in managing tissue ischemia–reperfusion (I/R) injury. However, the imprecise structures of most developed nanozymes pose significant challenges for their structure–activity interpretation and clinical translation. Additionally, the monotonous enzyme-like activity exhibited by most nanozymes also restricts their efficacy. In this study, we have developed well-defined cascade nanozymes based on metal organic cages (MOCs) to effectively eliminate excessive ROS in the context of renal I/R injury. By integrating nickel and cobalt within the MOC, we obtained heterometallic organic cage (HMOC) nanozymes with adjustable metal ratios. The incorporation of these two metals into a single MOC nanozyme not only expands its catalytic activity but also enables it to facilitate complex antioxidant reactions more effectively than traditional multi-step processes. The performance of HMOC cascade nanozymes, which mimic the cascade activities of superoxide dismutase (SOD) and catalase (CAT), in converting superoxide anion radicals (O 2 –) into oxygen and water is synergistically enhanced by the heterometallic interactions within a single metal cluster in the HMOC structure. Through optimization of the metal ratio within HMOC-2, both in vitro and in vivo experiments demonstrate that its ROS-scavenging capacity surpasses that of other groups significantly, thereby effectively alleviating renal I/R injury. This study not only presents well-defined enzyme-like cascade systems but also highlights their promising therapeutic potential for treating renal I/R injury. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Z-type Fe 2 O 3 /MoO 3 heterojunction was synthesized for the PEF-like system. • Simultaneously proposed 1O 2 generation and CIP degradation. • Fe 2 O 3 /MoO 3 could generate and activate H 2 O 2 in the PEF-like system. • ·O 2 − and H 2 O 2 were sources of 1O 2 in the FMO-1-PEF-like system. Singlet oxygen (1O 2), a typical reactive oxygen species (ROS) with selective oxidation properties, holds great application prospects in water environment treatment. However, the 1O 2 generation mechanism in photo-electro-Fenton-like (PEF-like) system for water purification is still unclear. In this study, we developed a Fe 2 O 3 /MoO 3 (abbreviated as FMO-x) Z-type heterojunction and achieved efficient degradation of ciprofloxacin (CIP). In-situ irradiated XPS, EPR, and DFT calculations confirmed that the coupling interface of FMO-1 Z-type heterojunction effectively enhanced the charge separation and transfer process, thus generating various ROS (1O 2 , ·O 2 −, ·OH and H 2 O 2). In the FMO-1-PEF-like system, H 2 O 2 was generated in-situ through 2e− ORR. In addition, ROS quantitative experiments showed that the yield of 1O 2 , ·O 2 − and ·OH was 29.76, 92.54 and 1.09 μmol·L−1 in 60 min, respectively. EPR and XPS results indicated two potential routes for the 1O 2 generation: the reaction between ·O 2 − and Fe3+ and between ·O 2 − and H 2 O 2. In the FMO-1-PEF-like system, the removal rate of CIP was 97.10 % in 60 min, and the kinetic constant was 0.0626 min−1, which was 1.32 and 1.55 times higher than that of Fe 2 O 3 and MoO 3. This work developed a method using Fe 2 O 3 /MoO 3 Z-type heterojunction to understand the mechanism of the 1O 2 generation in the PEF-like system. [ABSTRACT FROM AUTHOR]

• Oxygen transfer in CL is important to design CL and manage fuel cell. • Review oxygen transfer mechanism and resistance in Pt/C/polymer, porous aqueous CL. • Several mass transfer pathways for oxygen in mesoporous CL are proposed. • Oxygen solution via interface is main factor affecting its transfer. • Dynamic oxygen transfer mechanisms in aqueous CL needs further study. Oxygen transfer in catalyst layer (CL) is an important issue affecting the oxidation–reduction reaction (ORR) and the output voltage of fuel cells, which is significant for guiding high-performance catalyst and CL design, and steady fuel cell operation for avoiding water flooding and degradation. Apart from the research on catalyst with low- and zero- loading platinum, high oxygen-transfer CL is another hot spot, the result of which will be beneficial to both proton exchange membrane (PEM) fuel cell and its inverse water electrolysis. In this paper, oxygen transfer is systematically reviewed involving oxygen transfer mechanism, model description, oxygen transfer resistance characterization, model solution method, and finally the oxygen transfer investigation in water-filled CL. For the transfer mechanism, in two scales that the studies are consecutively reviewed, which are Pt/C-ionomer agglomerate and porous CL. Among three main transfer paths, different factors influencing oxygen transfer are also clarified. At the point of fuel cell application, the oxygen transfer resistance and impedance, structure modeling and solution for oxygen transfer model, especially the oxygen transfer in water-involved CL are reviewed as well. Some view points on future research are proposed. Firstly, direct experimental validating oxygen transfer mechanism in agglomerate, CL, and water-involved CL should be given more attention. Secondly, the oxygen transfer and water content under transient conditions in CL still need to be closely monitored in terms of oxygen transfer resistance via mathematical methods that combining the basic transfer mechanism and proper structural establishment, where the traditional low-frequency impedance affecting oxygen transfer at large water amount needs more investigations. This paper is of great significance for the forward design of CL as well as fuel cell operation management. [ABSTRACT FROM AUTHOR]

• The CsPbX 3 @SiO 2 phosphor was prepared by high temperature calcination and alkali etching process。 • The phosphor revealed excellent photoluminescence (PL) efficiency and stability. • After alkali etching, the PL efficiency of CsPbX 3 @SiO 2 reached 86.7 %, which was stable for more than 14 h under boiling water conditions. • Highly brightness and stable membranes were created which used for white LED. To overcome the poor stability of metal halide perovskite nanocrystals (NCs) prepared in organic solvents, a solid reaction method at high temperature was developed using sol–gel porous SiO 2 as a reactor. Sol-gel SiO 2 powders were used to encapsulate CsPbX 3 NCs at high temperatures (600–800 °C) in air to get SiO 2 /CsPbX 3 glass by dispersing growth cites in advance and no ligands added. After NaOH etching, a thin dense SiO 2 shell was remained on the surface of CsPbX 3 NCs (named as CsPbX 3 @SiO 2).The photoluminescence (PL) quantum yield of the CsPbX 3 @SiO 2 was 86.7 %, in which their PL peak wavelengths were adjusted from 410-707 nm by changing halogen components. The dense SiO 2 shell on CsPbX 3 NCs blocked the connection of CsPbX 3 cores with water and oxygen in the external environment, resulting in CsPbX 3 @SiO 2 revealed extraordinary high stability. After immersing in water for half year, the PL intensity of CsPbX 3 @SiO 2 composites was remained unchanged and the composites still revealed bright PL after heat-treating in boiling water for 14 h. These highly stable composites were used to fabricate a white light-emitting diode, in which the color coordinates are located at (0.36, 0.33), and the color temperature reaches 5169 K which belongs to the warm white light range. [ABSTRACT FROM AUTHOR]

[Display omitted] • N,S-CS/CN achieved the high H 2 O 2 activity in acid, neutral and alkaline conditions. • The carbon-based heterostructures could effectively avoid the charge recombination. • The synergistic effect of S- and N-site was conducive to H 2 O 2 production. Photoelectrocatalytic (PEC) H 2 O 2 synthesis from water and oxygen is a prospective approach for the manufacture of solar fuels and value-added versatile chemicals. However, the development of the efficient photocathode remains a formidable challenge because of the inferior selectivity and yield of H 2 O 2 derived from the multiple electron transfers affected by pH conditions. Herein, we report a metal-free carbon-based heterostructure material with N, S co-doping, where binary heteroatom-doped carbon sphere (N,S-CS) is loaded on carbon nitride (C 3 N 4) polymer, achieving an efficient synthesis of H 2 O 2 in a wide pH range. DFT calculations and experimental results uncover that S- and N-site can suppress the O-O cleavage and facilitate the *OOH formation through their subtle microenvironment, mediating the superior 2e- oxygen reduction selectivity to H 2 O 2 in acids and alkalis, respectively. This work provides a cost-effective strategy for designing an efficient photocathode for H 2 O 2 production in a wide pH environment. [ABSTRACT FROM AUTHOR]

An emerging organic structure with excellent 2e- oxygen-reduction activity in the photosynthesis of H 2 O 2 has been developed, of which the photocatalytic performance was significantly improved after anchoring the active moiety into extending conjugated covalent organic frameworks. The resulting materials rendered high H 2 O 2 productivity in pure water. [Display omitted] • An emerging organic photocatalytic structure for the photosynthesis of H 2 O 2 from oxygen and water has been developed. • Extending conjugated COFs promotes H 2 O 2 productivity in pure water. • The suitable distance of active moiety generates the highest efficiency. • An alternative strategy for constructing 2e- oxygen reduction photocatalyst. Direct synthesis of hydrogen peroxide (H 2 O 2) using oxygen and water through the photocatalytic route is a prospective approach for the on-site production of H 2 O 2. However, the limited varieties of photocatalytic sites and ambiguous structure-active relationship impede the development of environmentally friendly technology. Herein, we report a active compound (benzotrithiophene, BTT) for the photosynthesis of H 2 O 2 using oxygen and water, and design four benzotrithiophene-based 2D covalent organic frameworks (BTT-COFs) linked with aromatic amines linkers. Significant enhancement in photocatalytic activity has been observed via the introduction of BTT struct into 2D COFs. The high crystallinity of COFs increases the visible light absorption ability and photostability of BTT. The suitable distance of BTT struct in COFs and the construction of donor–acceptor (D-A) structure further promote the carrier generation and transfer. The COF-BTT-TAPT exhibited the highest H 2 O 2 production rate of 620 μmol g−1 h−1. Mechanism investigation experiments have given the validation that BTT-COFs efficiently reduce oxygen in pure water to form H 2 O 2 under visible-light irradiation. This work paves a revolutionary way for designing and fabricating high-performance metal-free photocatalysts for visible-light-driven H 2 O 2 production. [ABSTRACT FROM AUTHOR]

• BON-Ov/CN chemically bonded heterojunction was successfully prepared. • The interfacial Ovs induces a strong IEF to boost the charge transfer. • This heterojunction exhibits the highest charge separation efficiency. • It shows enormously promoted photocatalytic H 2 O 2 production activity. Photocatalytic production of hydrogen peroxide (H 2 O 2) can convert low-density solar energy into storable chemical energy by only utilizing water and oxygen as feedstock, and sunlight as stimulator. However, it is encountered a great deal of hurdles for further improving the photocatalytic H 2 O 2 production, such as the narrow light absorption range of a single semiconductor, low separation efficiency of photogenerated electron-hole pairs and limited surface active sites. Although construction of heterojunction is an effective tactic to modulate the charge transfer path and improve the utilization of visible light, realizing close interfacial contact with a strong interfacial electric field (IEF) remains challenging. Herein, we construct a chemically bonded heterojunction, abbreviated as BON-Ov/CN, which consists of g-C 3 N 4 and Bi 2 O 2 (NO 3)(OH) decorated with oxygen vacancies (Ovs) to solve all the above problems in one fell swoop. The optimal BON-Ov/CN exhibits a photocatalytic H 2 O 2 production performance of 706.2 µmol L-1, which is 19.1, 14.9 and 4.9 times higher than that of BON, BON-Ov and CN, respectively. It was demonstrated that the largely enhanced catalytic activity is attributed to the type-II heterojunction between BON-Ov and CN. In particular, the introduction of Ovs on BON can induce a strengthened IEF to boost the interfacial directional charge transfer and enhance its surface active sites to some extent. This study offers a fresh perspective on improving interfacial charge migration of heterojunctions by vacancy-induced IEF regulation strategy. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fundamental mechanism for the excellent photocatalytic performance of Ag 3 PO 4. • Synthesis methods for Ag 3 PO 4 with high photocatalytic performance. • Barriers and solutions for the practical application of Ag 3 PO 4. Abstract Semiconductor photocatalysis is an extremely promising technology to deal with the far-reaching issues we need to face, such as the shortage of renewable-energy resources and the increasingly serious worldwide environmental problems. Ag 3 PO 4 is an excellent visible-light-driven photocatalyst, showing an extraordinary photoactivity for oxygen evolution in water splitting and degradation of pollutant in aqueous solution. However, due to the uncontrollable photocorrosion phenomenon, the Ag 3 PO 4 -based photocatalysis is still at laboratory scale. To remove the obstacles for practical application and to further improve its photocatalytic performance, this review summarized the achievements that have been made in this field. We began with an effort to introduce the reasons for Ag 3 PO 4 exhibiting excellent photocatalytic performance. Subsequently, the different synthesis methods of Ag 3 PO 4 were discussed. Finally, we outlined the barriers that hindered the practical application of Ag 3 PO 4 and proposed the ways to remove these barriers. This review also underlined the crucial problems that should be addressed prior to practical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plasmon-assisted chemistry was used for spatial-selective Ti 3 C 2 T X modification. • Grafting of flakes edges prevents the initial stage of their oxidation. • Flakes were tested in HER and OER regime as catalyst (or co-catalyst). • Increase in flakes stability was demonstrated at HER and OER conditions. The MXene flakes are considered excellent materials for a range of applications and device construction. Especially attractive is the utilization of MXenes as the catalysts or co-catalysts for water splitting, including both half-reactions – hydrogen (HER) and oxygen (OER) evolution. However, the MXenes exhibit a strong tendency to oxidize during utilization, especially in water media and at oxygen presence. The oxidation of the MXene flakes commonly starts from the edges and then proceeds to the basal planes. Since the catalytic activity of flakes is mostly related to the basal plane, strong covalent blocking of flake edges can significantly protect MXene in oxidative conditions and increase the flake's lifetime without the loss of their catalytic activity. In this work, we demonstrated the combination of plasmon-assisted chemistry and electrochemistry for spatial-selective and precise modification of MXene (Ti 3 C 2 T X) flake edges. Our approach is based on the spatial distribution of plasmon energy under the flake's illumination with infrared (IR) light. Plasmon local excitation leads to homolysis of the modification agent – iodonium salt, the formation of highly reactive radicals, and their immediate grafting to the edges of MXene flakes in the neighborhood. As a result, the edges of the flakes are protected, and the initial stage of their oxidation is prevented. After optimization of plasmon-assisted grafting, the modified flakes were tested in HER and OER and a significant increase in flakes stability was validated. [ABSTRACT FROM AUTHOR]

• PEMFC model has been applied to six different cathode flow field designs. • Cell performance is substantially improved by an orifice-shaped flow field design. • Improvement is around 70–170 mV at 2.5 A/cm2 compared to traditional designs. • Enhancement is mainly due to improved oxygen supply and water removal. In this study, a multiscale, multiphase polymer electrolyte membrane fuel cell (PEMFC) model was applied to simulate the cell performance of six cathode flow field designs. These designs included conventional flow field layouts (with trapezoidal and rectangular cross-sections) as well as orifice-shaped flow field designs featuring various narrowing section arrangements. The simulation results indicated that, in general, the orifice-shaped flow field designs yielded higher oxygen concentrations within the cathode side and exhibited superior water removal capabilities compared to conventional flow field designs. This study further revealed that the positioning of the narrowing section significantly influences cell performance, with enhanced performance noted in the orifice-shaped design that incorporated a zigzag pattern between adjacent channels. This pattern outperformed the side-by-side arrangement, implying that the zigzag configuration offers a superior advantage in optimizing oxygen supply and water removal. [ABSTRACT FROM AUTHOR]

Four sulfonamides, viz. sulfadiazine (SD), sulfamerazine (SM), sulfadimethoxine (SDM) and sulfachloropyridazine (SCP), were selected as model compounds to be degraded in Fe 2+ /S 2 O 8 2− system with a Fe 2+ :S 2 O 8 2− molar ratio of 1:4. The results of degradation kinetics indicate that the rate constants follows the order of SD > SM > SDM > SCP, and the aromatic and heteroaromatic rings of the sulfonamides are relatively low in reaction activity. Both hydroxyl radicals ( OH) and sulfate radicals ( SO 4 − ) are responsible for the degradation of sulfonamides, with the latter playing a more significant role. The theoretical results suggest that OH are majorly involved in the H-abstraction and addition reactions of the sulfonamides. Nonetheless there is single-electron transfer between the SO 4 − and sulfonamides, which results in oxidation of –NH 2 group and Smiles rearrangement. Based on the experimental and theoretical results, the degradation intermediates and degradation pathways are verified. At the initial stage of degradation, there is cleavage of S-N bond, hydroxylation of parent compounds, Smiles rearrangements and oxidation of –NH 2 . It is found that the incomplete mineralization of sulfonamides results in increase of acute toxicity. The study sheds light on the fate and transformation of sulfonamides under the attack of reactive oxygen species in environmental water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-supported 3D Co 3 O 4 /NC with abundant oxygen vacancies was prepared. • The N-doped carbon avoided the inactivation of the Co 3 O 4 active sites. • The oxygen vacancies activated lattice oxygen during the water oxidation. • The 3D Co 3 O 4 /NC-250 exhibited a low overpotential of 225 mV at 10 mA cm−2. The development of low-cost, efficient and robust non-precious metal electrocatalysts for acidic oxygen evolution (OER) is a major challenge. A novel self-supported N-doped hierarchical Co 3 O 4 (3D Co 3 O 4 /NC-250) electrocatalyst with abundant oxygen vacancies was prepared by a facile carbonization-oxidation process. XAFS and EPR results clarified that N doping regulated electronic state of central Co atom to generate abundant oxygen vacancies, which activated lattice oxygen in the water oxidation process. The key intermediate O*O was observed via in-situ ATR-FTIR, providing direct evidence for LOM mechanism on active oxygen vacancy sites. DFT calculations showed that LOM mechanism on oxygen vacancy sites was conducive to reduce adsorption free energy of oxygen-containing intermediates in limiting steps of acidic OER process. The as-prepared 3D Co 3 O 4 /NC-250 electrocatalyst exhibited ultra-high OER performance with a low overpotential of 225 mV at 10 mA cm−2 in acidic media. This study provided a new insight to rational design of efficient transition metal-based electrocatalysts for acidic OER. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFT studies show doping of Ce and Al into LaCoO 3 facilitates formation of oxygen vacancies. • Oxygen vacancies enhance adsorption of oxygen and water molecules. • Ce,Al-codoped LaCoO 3 prepared by a solgel method with abundant oxygen vacancies. • Doping leads to a reduced bandgap and enhanced absorption in the visible range. • Enhanced photodynamic activity towards E. coli under visible light irradiation. Perovskite-type lanthanum cobaltate (LaCoO 3) has been attracting extensive attention in photocatalysis; yet the performance is generally limited by the low structural defects and poor oxygen migration. Herein, results from first principles calculations show that Al and Ce codoping at the A and B sites of LaCoO 3 can induce the formation of oxygen vacancies, which, along with the exposed Co (0 1 2) facets, facilitate the adsorption of oxygen and water molecules, a critical step in the photocatalytic production of reactive oxygen species that are known as potent antimicrobial agents. Motivated by these theoretical insights, Ce and Al codoped LaCoO 3 is prepared experimentally via a simple sol–gel procedure. Spectroscopic measurements show that the cationic doping leads to the generation of abundant oxygen vacancies and Ce4+/Ce3+ species, fast electron transport, as well as a reduced band gap, as compared to the undoped counterpart. These unique structural characteristics enhance the separation and transport of photogenerated carriers and hence the generation of reactive oxygen species. Indeed, the obtained La 0.9 Ce 0.1 Co 0.9 Al 0.1 O 3 exhibits excellent photocatalytic antibacterial activity, where 98.8% of Escherichia coli is eliminated with La 0.9 Ce 0.1 Co 0.9 Al 0.1 O 3 at 1 mg mL−1 under visible photoirradiation for 30 min, in comparison to only 46.8% with undoped LaCoO 3. These results underline the significance of structural engineering in enhancing the photocatalytic activity of perovskite materials for antibacterial applications. [ABSTRACT FROM AUTHOR]

• Carbon aerogels of few-layer graphene skeletons by pyrolysis of hydrogel precursors. • Low mass density and high electrical conductivity due to NaCl crystal templates. • ORR activity from the resulting N -doped carbon aerogels. • OER activity from Ni3+ species by Fe(OH) 3 oxidation in adsorbed NiFe-LDH colloids. • High-performance bifunctional oxygen catalysts for water splitting and zinc-air batteries. Low-cost, high-performance oxygen catalysts are critical for electrochemical water splitting and metal-air batteries. Herein, carbon aerogels with skeletons consisting of few-layer graphene are derived pyrolytically from a hydrogel precursor using an array of NaCl crystals as the template, exhibiting a high electrical conductivity (869 S m−1) and an ultralow mass density (11.1 mg cm−3). The deposition of NiFe layered double hydroxide (NiFe-LDH) nanocolloids renders the aerogels active towards both the oxygen reduction/evolution reactions (ORR/OER), with the performances highly comparable to those of commercial benchmarks in both alkaline and neutral media. Results from operando Raman spectroscopy measurements and first principles caculations suggest that Fe(OH) 3 colloids facilitate the oxidation of Ni2+, which lowers the energy barrier to 0.42 eV for OER, whereas the nitrogen-doped carbon aerogels are responsible for the ORR activity. With the composites used as bifunctional oxygen catalysts for electrochemical water splitting and rechargeable zinc-air batteries, the performances in both alkaline and neutral media are markedly better than those based on the mixture of commercial Pt/C and RuO 2. Results from this study highlight the unique advantages of ultrathin graphene aerogels in the development of effective catalysts for electrochemical energy devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-assembly of Janus flake filler (JNS) by sol–gel self-polymerization. • Take full advantage of JNS' amphiphilia and interface compatibility. • JNS waterborne coatings provide long-term corrosion protection. • Successfully prepared a waterborne coating with the properties of a 'hexagonal warrior'. • Expand Janus' application areas and promote the integration of disciplines. Environmentally friendly waterborne coatings tend to form polar pathways due to more hydrophilic groups, resulting in poor coating corrosion resistance and reduced coating service life. The anisotropic Janus is used as a filler for waterborne epoxy (WEP) coatings to reduce the number of hydrophilic groups and improve interface compatibility by cross-linking the hydrophilic end with the resin; at the same time, the hydrophobic groups are used to improve the water resistance of the coating. In this paper, we synthesized sheet-like silica Janus (JNS) materials by interface-induced self-assembly via sol–gel reaction in oil-in-water emulsions to prepare novel water-based JNS/WEP anticorrosion coatings. The excellent corrosion resistance of JNS/WEP coatings is explained by the fact that the hydrophilic end of JNS reduces internal defects in the coating and enhanced interfacial interaction; the hydrophobic end improves the water resistance of the coating. Similarly, the physical barrier advantage of flake JNS is brought into play to reduce the high availability of water and oxygen, inhibit electrochemical corrosion on the surface of carbon steel and form a passivation film; the active group at the hydrophilic end of JNS can be chelated with Fe3+ for active protection by synergistic. Among them, immersed in 3.5 wt% NaCl solution for 130 days, the impedance modulus of 1.0 % JNS/WEP coating is 2 orders of magnitude higher than that of WEP coating, up to 2.59 × 1010 O cm2. Therefore, it exhibits outstanding anti-corrosion performance under multiple synergistic protection. [ABSTRACT FROM AUTHOR]

Blocking the transition between the dyes in monomer and aggregate states displaying complementary emission in solid polymeric network allows generation of stable white emission. [Display omitted] • Solid densely-woven polymeric net-work is created. • The net-work restricts the motion of doped dyes. • Dye displays white emission composed of blue monomer and yellow aggregate emission. • Densely-woven polymeric net-work resists oxygen and water. • The white emission is stable against temperature, oxygen, and water. Single molecular white emissions are difficult to achieve owing to the challenges in delicately manipulating the intensity of complimentary emissions. Many emissive dyes display complimentary emissions in monomer and aggregated states, but the aggregate growth in solution or in solvent evaporating process always results in unstable white emission due to the formation of macrophases of the aggregates. Herein we report that by blocking the growth of the aggregate in the densely-woven solid polymeric network, the complementary monomer and aggregate emission can be firmly locked, so that ultra-stable single molecular white emission display excellence tolerance to humidity, water, organic vapors and extreme temperatures can be achieved. [ABSTRACT FROM AUTHOR]

• Molecular design strategies for efficient luminescence of nonconventional luminogens were established. • The photoluminescence efficiency of nonconventional luminescent small molecules reached 59.8 %. • It is the first report of nonconventional luminescent materials for targeting lysosomes. The design and synthesis of organic nonconventional luminescent (NL) materials with efficient emission have attracted significant attention. However, these materials usually suffer from the fact of low photoluminescent quantum efficiency (Φ), poor tunability of emission wavelength, and non-luminescence in dilute solution, limiting their further application. Herein, rational molecular design strategies for NL compounds with efficient and tunable emission in dilute solution were presented via theoretical calculation and practical verification. Firstly, increasing the ratio of π → π* transition in the excited state to suppress the n → π* transition, inhibit intersystem crossing, and avoid the generation of triplet excitons which can be easily quenched by water or oxygen. Secondly, introducing strong intramolecular hydrogen bonds to suppress intramolecular rotation and inhibit non-radiative transitions. Besides, D-π-A structure can effectively adjust the luminescence color. Based on the proposed design strategies, two novel compounds named LJ-1 and LJ-2 were synthesized, both compounds can emit bright green fluorescence in dilute solution with Φ of up to 59.8 %, and their photophysical properties are pH-dependent. The results showed that pH had a great impact on the strength of intramolecular hydrogen bonds and the degree of conjugation. For example, the emission wavelength of LJ-1 exhibited red-shift as the increase of pH value. Furthermore, LJ-1 can be used for visual detection of Ag+ in water solution in naked eye and the precise localization of lysosomes. We believe that our work will greatly broaden the application range of nonconventional luminogenic compounds in future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Overview and comparison of bio-oil obtained from thermochemical processes. • HTL bio-oil has high heating value 35.7 MJ/kg. • Upgradation techniques of bio-oil to value-added products are reviewed. • Transesterification and steam reforming require catalysts development. • Most of these techniques are at R&D phase. The bio-oil obtained from thermochemical conversions of biomass (wood and agriculture waste, animal waste, solid waste etc.) can be an alternative to conventional liquid fossil fuels used in transportation or industrial sectors. However, bio-oil in its raw form is not of good quality as a fuel compared to conventional fossil derived fuels. In particular, bio-oil in its raw form has a low heating value, high oxygen and water contents, high viscosity and corrosive behavior. So, bio-oil needs to be upgraded for its direct use as a fuel. Meanwhile, the different kinds of valuable products can be derived from bio-oil: biofuels, biochemicals, and biopolymers when bio-oil is upgraded. The conversion of bio-oil into useful products has been the focus of numerous studies. Thus, it is crucial to study the research progress of this area to get the data needed to evaluate the viability of various processes for using bio-oil as feedstock in a comparative manner. Hence, this review article focuses on these value-added products and is twofold. The first fold explains the pyrolysis and hydrothermal liquefaction of biomass and compares the bio-oil properties obtained from both methods. Further, the second fold explains the key insights and respective state-of-the-art of generation techniques of value-added products from bio-oil in detail. In addition, value-added products from catalytic pyrolysis and their respective applications are also briefly discussed. Finally, the challenges and prospects of these techniques are presented. Based on this study, most of these technologies are still in the research and development (R&D) phase and cannot be scaled up due to technological limitations and cost intensive. [ABSTRACT FROM AUTHOR]

• Rational principles guide to improve the performance of electrocatalysts for H 2 O 2 production are summarized. • Promising catalysts based on 2e-ORR and 2e-WOR are summarized. • The mechanisms of enhancing catalytic activity and selectivity are clarified. • Indicators for the performance of electrochemical H 2 O 2 production are analyzed. • Practical applications of in-situ electro-generated H 2 O 2 in water are shown. At present, large-scale hydrogen peroxide (H 2 O 2) production is mainly produced via anthraquinone process, which is subject to challenges in transport and storage. Direct electrochemical hydrogen peroxide production (EHPP), a promising alternative to solve the aforementioned issues, has been explored over the past decades, driven by fabricating novel electrode materials with unique catalytic properties, as well as exhibiting outstanding performance in terms of high activity and selectivity toward H 2 O 2 and maintaining long-term stability. Here, we first reviewed the historical development of EHPP, followed by outlining current advances in this promising technology with particular attention given to criteria for rational design (e.g., density functional theory calculation guided by computational simulation), electrocatalysts for oxygen reduction and water oxidation reaction via two-electron pathway. Finally, we conclude this state-of-the-art review by considering reactor configurations from in-situ EHPP to on-site practical environmental applications, as well as discussing the challenges that should be addressed in the future. [ABSTRACT FROM AUTHOR]

• The role of water in the deterioration process of VO 2 is discussed. • Humidity is a key factor in the rate of VO 2 natural aging. • Water affects the adsorption of oxygen on VO 2 surfaces by hydrogen bonding. • Water is involved in the reaction in the form of combined water. • Water accelerates aging by destroying the dense structure of VO 2. Vanadium dioxide (VO 2) has already been widely concerned as a thermochromic smart window material. However, the Achilles heel of VO 2 is susceptible to degradation by water and oxygen in the air, which has limited its commercialization. Until now, it has remained unclear what effect water has on the deterioration of VO 2 , hindering the solution to this dilemma. In this work, the degradation mechanism of VO 2 during natural aging was proposed based on density functional theory (DFT) calculation and experimental analysis, and the role of water in the degradation process was discussed in detail. The results showed that water affects the deterioration reaction by influencing the adsorption behavior of oxygen on the VO 2 surface, destroying the dense structure, and participating in the reaction in the form of combined water. This work fills the degradation mechanism gap of VO 2 , helps to design high-performance structures of VO 2 -based smart coatings, and provides theoretical guidance to solve the problem of VO 2 weatherability. [ABSTRACT FROM AUTHOR]

The efficient CO 2 photoreduction device with internal electric field is realized by introducing a layer tandem structure made up of g-C 3 N 4 and an inorganic lead-perovskite (CsPbBr 3). The device satisfies full artificial photosynthesis of CO 2 conversion and exhibits good stability. [Display omitted] • The efficient CO 2 photoreduction device is constructed based on CsPbBr 3 perovskite. • Tandem structure of CsPbBr 3 /g-C 3 N 4 promotes directional charge-carrier migration. • The photo-CO yield rate is 238.7 μmol m-2 h−1 under a humid gaseous CO 2 system. The design of efficient photocatalytic devices is of great significance to achieve low-cost carbon dioxide reduction into solar fuels. Herein, directional charge-carrier migration is realized by introducing a CO 2 reduction device with a tandem structure made up of g-C 3 N 4 and an inorganic lead-perovskite (CsPbBr 3). This photocatalytic device shows a significantly increased CO 2 photoreduction rate in a humid gaseous CO 2 system when compared to the parental g-C 3 N 4 layer. This "full artificial photosynthesis" thereby generates fuel molecules and oxygen from water and CO 2, only, without any co-catalysts or sacrificial agents. To our surprise, the device maintains greater than 90% of the CO production yield after 5 days continuous irradiation. The existence of internal electric field is confirmed, which drive the directional movement of photogenerated charge-carriers with the perovskite being reductive, while the carbon nitride with its enormous oxidation stability is covering the oxidation processes. This represents a promising possibility for the practical application of CO 2 photoreduction with scalable devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A green process coupling photoreaction, extraction, and separation for on-site H 2 O 2 production. • Direct H 2 O 2 photocatalytic generation reaction in pure oily alcohol without water. • Amphiphilic g-C 3 N 4 dispersed on phase interface for easy separation and recovery. • Rapid and high-efficiency H 2 O 2 extraction from benzyl-alcohol by water. • Rapid separation of H 2 O 2 solution and benzyl-alcohol with superhydrophobic mesh. • Obtaining H 2 O 2 aqueous solution product with adjustable and usable high concentration. Hydrogen peroxide (H 2 O 2) can be photocatalytically generated by oxygen in water with fatty alcohols as a sacrificial agent; however, it is expensive to separate because of the miscibility of fatty alcohols and water. In this work, H 2 O 2 is directly generated photocatalytically using amphiphilic graphitic carbon nitride (g-C 3 N 4) and oxygen in pure anhydrous oily benzyl alcohol (BA) alone; it is simply extracted by water and separated using a hydrophobic/lipophilic mesh to obtain a high-concentration H 2 O 2 aqueous solution. The results show that the H 2 O 2 concentration in BA after 4 h of photoreaction is 9.45 mM and that of the final solution product can be as high as 70.93 mM in water. Water does not enhance the photoreaction; instead, unexpectedly, it weakens it. However, it is possible to completely extract the H 2 O 2 from the reacted BA. In this study, the H 2 O 2 solution is rapidly separated from the BA with a separation efficiency of 99.97% using a hydrophobic mesh. The photocatalyst g-C 3 N 4 is present at the water/BA interface owing to its amphiphilicity, and it can be caught by the mesh during separation and reused after backwashing. The combined photoreaction, extraction, and separation processes provide a simple, environment-friendly, and rapid H 2 O 2 photogeneration process for the on-site production of a usable H 2 O 2 solution. [ABSTRACT FROM AUTHOR]

[Display omitted] • The catalytic performance of rhodium catalyst is enhanced via boron modification. • The present catalyst displays high activity for water splitting and oxygen reduction. • DFT has been performed to reveal the mechanism for advantage. • A corner-induced-selective-deposition process is observed in catalyst synthesis. The research of active and efficient electrocatalysts is of great importance for the practical application of some energy conversion devices. Improving the catalytic activity and utilization efficiency of noble metal is of great importance for the practical application. Here, we report a one-pot synthesis of porous rhodium octahedra through a corner-induced-selective-deposition (CISD) process. After simple interfacial boron modification, the performances towards oxygen evolution reaction (OER), hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) in alkaline media were greatly enhanced. Especially, a small overpotential of 31 mV at 10 mA/cm2 was achieved for HER, and a high half-wave potential of 914 mV was obtained for ORR, much better than the commercial Pt/C catalysts (55 mV, 891 mV). Density functional theory (DFT) calculation reveals that the boron incorporation optimizes the adsorption properties of catalyst surface and in turn, lowers the overpotentials for the three reactions. This work may be extended to design other nanoscale functional materials with delicate nanostructures and optimized compositions. [ABSTRACT FROM AUTHOR]

Highlights: [•] The bio-iron system showed sufficient NB removal capacity. [•] Positive effects were obtained with additional organic substrates. [•] Nitrate suppressed the bio-iron system performance. [•] Dissolved oxygen and sulfate improved the NB removal. [•] AN elimination occurred with the existence of oxygen, sulfate and nitrate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Experiment and kinetic modeling of Passive NOx adsorption (PNA) over Pd/SSZ-13. • A kinetic model was developed for PNA performance for different operating conditions. • A detailed mechanism for the roles of CO in passive NO x adsorption has been derived. • A thermal converter model was developed to assess real-life conditions. Passive NO x adsorption (PNA) has been recently developed as a promising technology for controlling the NO x emissions during the cold start period. In this work, we illustrate a CO-assisted mechanism by combining experimental and kinetic modeling studies. Pd/SSZ-13 has been synthesized, characterized and evaluated as a PNA in low-temperature NO x adsorption and temperature program desorption cycles, to represent multiple cold start periods. The gas compositions were also systemically changed, where both the effect of varying NO x and CO feed was evaluated in the presence of high water and oxygen contents. A kinetic model was developed to simulate the profiles of NO and NO 2 , including three initial Pd sites (Z-Pd(II)Z-, Z-[Pd(II)OH]+ and PdO). It is concluded from XPS and in situ DRIFTS experiments, flow reactor measurements and modelling observations that CO reduces Pd(II) species to Pd(I)/Pd(0) species, which increases the stability of the stored NOx species, resulting in a release above the urea dosing temperature. The model could well describe the experimental features, including the effect of CO. In addition, the model was used for full-scale catalytic converter simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The in-situ polymerization via illuminating and methyl methacrylate was firstly proposed. • The hybrid FAPbBr 3 QDs-polymer nanocomposites show enhanced stability and fluorescence. • The transparent nanocomposite films with strong blue, green and red emission were prepared in large area. • High color temperature and lumen efficiency WLED was constructed. It has been proved that perovskite quantum dots (QDs) have great potential in optoelectronic devices because of their excellent optical performance. However, low stability against water and oxygen environment hinders the commercial application of down-conversion display films on account of its highly ionic nature and low formation energy. Here, we demonstrate a convenient method to obtain a uniform, large-area water-oxygen-resistant quantum dot-polymer composite film via illuminating FAPbBr 3 QDs and methyl methacrylate (MMA) under white light emitting diode. We find that FAPbBr 3 QDs act as photo initiators, leading to the polymerization of organic monomers around the quantum dots. The obtained FAPbBr 3 QDs-polymer nanocomposites are independently dispersed coated with about 10 nm thick polymerized methyl methacrylate (PMMA). Due to the well protection of covered PMMA, the FAPbBr 3 QDs/PMMA nanocomposites show high tolerance to water and oxygen, and the increased PLQY and lifetime indicate the reduction of non-radiative recombination centers. Furthermore, the FAPbBr 3 QDs/PMMA nanocomposites are easy to produce large area films, and no agglomeration during films production by knife coating process. Then uniform, strong fluorescence, transparent and stable blue, green and red nanocomposite films can be prepared by optimizing the viscosity via controlling the reaction time. Finally, white LED was fabricated with a Lumen Efficiency of 80.4 m/W and Color Rendering Index of 90. Our work suggests that illuminated polymerization of perovskite quantum dots under white light emitting diode provides a simple and effective method to commercialization [ABSTRACT FROM AUTHOR]

• Methanol solvothermal treatment induces a hydroxylated surface on Fe 2 O 3 :Ti. • HCl hydrothermal treatment induces more chemisorbed oxygen on Fe 2 O 3 :Ti. • Surface hydroxylation enhances the photocurrent and chemisorbed oxygen reduces the onset potential of Fe 2 O 3 :Ti. • A synergistic effect is achieved by oxhydryl and chemisorbed oxygen. • The photocurrent density of Fe 2 O 3 :Ti is optimized to 3.0 mA cm−2 at 1.23 V RHE. Two types of oxygen defects are created on the Fe 2 O 3 :Ti photoanode and their acting roles on prompting the photoelectrochemical performance are clarified. Methanol solvothermal treatment is discovered to expediently import hydroxyl oxygen on Fe 2 O 3 :Ti. Accordingly, the charge carrier density is multiplied and surface hydrophilicity is dramatically improved, resulting in inhibition of surface transfer recombination and enhancement of the photocurrent density. In addition, HCl hydrothermal treatment can induce surface defects with chemisorbed oxygen, which barely affects the surface hydrophobicity or the carrier density. HCl hydrothermal treatment behaves on promoting the charge transfer in surface states as well as suppressing the bulk charge recombination, thus moderately enhancing the photocurrent density and lowering the onset potential. By combining two treatment processes, both defects are formed simultaneously with synergistic effectiveness. In addition, the FeCoW oxy–hydroxide electrocatalyst is incorporated for further accelerating the surface charge transfer. As a result, by compositing the strategies of methanol solvothermal, HCl hydrothermal, and FeCoW deposition, the photocurrent density of Fe 2 O 3 :Ti photoanode is significantly enhanced to 3.0 mA cm−2 at 1.23 V RHE with an onset potential of as low as 0.67 V RHE. [ABSTRACT FROM AUTHOR]

• Ni@NiO-CdS has both water reduction/oxidation catalytic activities. • Ni@NiO makes the S vacancy in CdS an effective electron trap. • Schottky junction acts as a pump for transfer of photo-generated carriers. • p-n junction of the catalyst reduce the recombination of electrons and holes. • The structure of catalyst extends the life of the photogenerated electrons and holes. The exploration of bifunctional catalysts to produce both hydrogen and oxygen will accelerate the progress of overall water-splitting. This paper introduces a facile method to fabricate bifunctional photocatalysts toward the water splitting by doping nano CdS with S vacancies on Ni@NiO nano-spheres. A serious of photocatalytic catalysts were developed and subsequently characterized, the two half-reactions of photocatalytic water splitting were studied in detail by using sacrificial agents, the hydrogen output at 41699 μmol g−1 h−1 (AQE 28.5%, λ = 420 nm) while the evolution of O 2 is as high as 55120 μmol g−1 h−1 (AQE 35.7%, λ = 450 nm). It is a strategy that the presence of Ni@NiO can trigger the S vacancy in CdS to act as an effective electron trap, the p-n junction of NiO-CdS, as well as the Schottky barrier between NiO and Ni, can change the dynamic characteristics of photogenerated electrons and prolong their life. These prolonged photogenerated electrons can initiate stable and effective photocatalytic redox reactions. [ABSTRACT FROM AUTHOR]