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As a typical wide-band-gap semiconductor, BiPO 4 (BPO) has a great potential for photocatalytical degradation of highly stable benzene (C 6 H 6 ) that has been regarded as a priority hazardous VOC substance in the indoor atmosphere. Hexagonal (H-BPO), monoclinic (M-BPO), and their mixture phase BiPO 4 (M/H-BPO) were selectively synthesized to study the effect of BPO phase structure on the degradation of C 6 H 6 . The samples were characterized by several techniques, including X-ray diffraction, FTIR spectroscopy, UV–vis diffuse reflection spectroscopy, N 2 absorption-desorption measurements, scanning/transmission electron microscopy, and X-ray photoelectron spectroscopy. The results indicated that the monoclinic phase was a thermodynamically stable phase. The band gap energy of H-BPO, M-BPO, and M/H-BPO was 3.74, 3.93 and 3.86 eV, respectively. A transformation from rice-like hexagonal BPO to monoclinic phase nanorods was realized through varying the hydrothermal temperature and the composition of the solvent. The degradation of C 6 H 6 was closely associated with the crystalline phase of BPO and the mineralization rates decreased in order of M– (7.3) > M/H– (1.51) > H-BPO (0.51 μmol·h −1 ·m −2 ). The rates were higher than that of well-known P25 (0.34 μmol·h −1 ·m −2 ). The highest activity of M-BPO could be ascribed to its intrinsic distortion of PO 4 tetrahedron and the largest band gap structure. OH, O 2 − , and photoinduced holes were the major oxidation species accounting for the destruction of C 6 H 6 . [ABSTRACT FROM AUTHOR]

A series of nebula-like ZnO/CeO 2 @HNTs heterostructure photocatalysts were synthesized via a novel one-step wet-calcination method for degradation of tetracycline (TC) under simulated solar irradiation. TEM, HRTEM, XRD, FT-IR, XPS, DRS, PL, PC, EIS and ESR techniques were applied for characterization of samples. And the potential structure of new photodegradation products was studied by HPLC–MS analysis. The characterization results revealed the enhanced photocatalytic activity of ZnO/CeO 2 @HNTs heterostructure photocatalysts due to the delayed recombination of photogenerated electron-hole pairs. Moreover, surface oxidation state analysis demonstrates that Ce 3+ and Ce 4+ states coexist in CeO 2 , which enhance the separation of electron-hole pairs though cerium oxide shifting between CeO 2 and Ce 2 O 3 under photocatalytic process. In addition, the effects of the calcinating temperature, the molar ratio of ZnO to CeO 2 and the dosage of HNTs on photocatalytic activity of ZnO/CeO 2 @HNTs heterostructure photocatalysts were researched and the best possible values have been found. Furthermore, the photodegradation mechanism was systematically investigated by active species trapping experiment. It revealed that OH radicals play a little role while hole and O 2 − are the more major reactive species in the photodegradation process. [ABSTRACT FROM AUTHOR]

[Display omitted] • SA-FeCNS-800 catalyst (2D nanosheet) for high-performance Zn-air batteries. • Catalyst showed stability and power density comparable to that of Pt/C catalysts. • SLS@PVA-SSE electrolyte showed excellent dendrite-free Zn deposition. • Flexible Zn-air batteries showed cycling over 85 h at 2 mA cm−2. • Study paves way for flexible, durable, and environment friendly energy systems. High-efficiency and low-cost electrocatalysts for oxygen reduction reaction (ORR), as well as gel electrolytes with high water retention, mechanical adaptability and zinc dendrites inhibition are required for flexible Zn-air batteries. Herein, abundant cellulose extracted from wood was employed to prepare ORR catalysts consisting of single iron atoms and Fe 3 O 4 nanoparticles embedded within nitrogen-doped carbon nanosheets (SA-FeCNS). The optimized SA-FeCNS-800 demonstrated remarkable ORR catalytic activity, showcasing a half-wave potential of 0.85 V vs. RHE and a diffusion-limiting current of 5.54 mA cm−2 at 0.3 V vs. RHE. Its efficacy was further demonstrated in Zn-air battery technology, where it exhibited superior discharging and charging capabilities, allowing for 618 h of continuous operation at 5 mA cm−2, along with enduring performance at high current densities (10 mA cm−2 and 20 % depth of discharge). Furthermore, a solid-state electrolyte named SLS@PVA-SSE was fabricated utilizing wood's sodium lignosulfonate-functionalized polyvinyl alcohol hydrogel. This innovation effectively curbed the formation of zinc dendrites and enhanced alkaline resistance, owing to the incorporation of positively charged sulfonate groups. The flexible Zn-air batteries assembled with SA-FeCNS-800 and SLS@PVA-SSE exhibit long cycling life of for 85 h at 2 mA cm−2 and 37 h at 5 mA cm−2. This study offers a sustainable and effective way to make high-performance catalysts and solid electrolytes for advanced flexible energy materials using renewable biomass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co–CeO 2 was used to activate the PMS for degrading PET plastics. • The degradation rate reached 91.61 % in 6 h after adding 1 mL H 2 O 2 and 5 mM PMS. • Several factors, such as pH and anions, were considered. • SO 4 − played a crucial role in the degradation, compared to OH, O 2 −, and 1O 2. • The possible mechanism of photocatalysis/PMS degradation of PET was proposed. Polyethylene terephthalate (PET) plastic, widely used for packaging owing to its excellent properties, has become a major contributor to plastic waste, for which satisfactory recycling and upgrading treatment technologies are lacking. In this study, Co-doped CeO 2 was used as a photocatalyst to degrade PET plastics in water, and PET degradation was measured according to the weight loss rate. Peroxymonosulfate (PMS) addition to the photocatalytic system enabled the degradation of 53.82 ± 4.48 % of PET plastics, highlighting the excellent PET plastic degradation capability of the photocatalytic PMS system. The study investigated the effects of the catalyst-to-plastic ratio, PMS concentration, initial pH, inorganic anions, humic acid concentration, and hydrogen peroxide (H 2 O 2) addition on the catalytic oxidation system. Contrast experiments revealed that H 2 O 2 addition to the photocatalysis/PMS oxidation system further improved the PET plastic degradation efficiency (91.61 ± 1.50 %). Liquid product analysis, electron paramagnetic resonance, and free radical quenching experiments confirmed that SO 4 − played the most significant role in PET degradation. Finally, a possible mechanism for the degradation of PET plastics in water using the photocatalysis/PMS oxidation system was proposed. [ABSTRACT FROM AUTHOR]

• A novel intercalated Co 3 O 4 -C/Ni 2 P 2 O 7 was prepared by simple chemical precipitation method. • The intercalated Co 3 O 4 -C/Ni 2 P 2 O 7 as new electrode materials exhibited great electrochemical properties. • Co 3 O 4 -C/Ni 2 P 2 O 7 products are ideal electrode materials for supercapacitors. Nickel pyrophosphate (Ni 2 P 2 O 7) is considered as a potential next-generation electrode material for supercapacitors. Here, we report a new type of cathode material for supercapacitors in, which consists of rhombic dodecahedron Co 3 O 4 -C growing on two-dimensional (2D) Ni 2 P 2 O 7 nanosheets. Surprisingly, Co 3 O 4 -C/Ni 2 P 2 O 7 materials exhibit bright electrochemical properties with a relatively high specific capacitance of 2537.78 Fg−1 and remarkable cyclic stability (88.5% after 3000 cycles). Therefore, the prepared Co 3 O 4 -C/Ni 2 P 2 O 7 electrode material is a significant candidate material for supercapacitors. The synthesis process is simple, low cost and environmentally friendly. Notably, Co 3 O 4 -C/Ni 2 P 2 O 7 products have excellent electrochemical properties and are candidate electrode materials for supercapacitors. The Co 3 O 4 -C/Ni 2 P 2 O 7 products have excellent electrochemical properties, which indicate the Co 3 O 4 -C/Ni 2 P 2 O 7 materials imply their promising potential applications in the energy storage. Most importantly, this work provides a scalable strategy for morphology-controlled synthesis of metal oxides by recrystallization. [ABSTRACT FROM AUTHOR]

[Display omitted] An integrated bifunctional electrocatalyst composed of CoPt nanoparticles uniformly distributed on the carbon nanosheet array is successfully synthesized, which exhibits much enhanced activity for both pH-universal hydrogen evolution and glycerol oxidation. This work demonstrates a successful paradigm for the design and preparation of integrated bifunctional electrocatalyst with potential applications in hydrogen production. • An integrated bifunctional CNs@CoPt electrocatalyst is successfully synthesized. • The CNs@CoPt exhibits superior activity for pH-universal HER and GOR. • A quite high utilization degree of Pt (35.1%) is achieved on CNs@CoPt. • The GOR-HER system based on CNs@CoPt shows boosted hydrogen evolution performance. Exploiting highly effective and low-cost electrocatalyst for water splitting is an instant challenge for the development of sustainable hydrogen energy. In this work, we report an integrated bifunctional electrocatalyst composed of CoPt nanoparticles uniformly distributed on the carbon nanosheet array (CNs@CoPt), which exhibits excellent activity for both cathodic hydrogen evolution in a wide range of pH conditions and anodic glycerol oxidation reaction. Based on this novel electrocatalyst, a hydrogen evolution coupled with glycerol oxidation system was constructed, exhibiting dramatically enhanced hydrogen production rate (48 L h−1 m−2) in cathode, larger than traditional water splitting system (27 L h−1 m−2), and gaining high-valuable product (formate, 113 g h−1 m−2) in anode. Moreover, a quite high utilization degree of Pt (35.1%) is achieved on CNs@CoPt owing to this hierarchical and alloy structure, 3.3 times higher than that of commercial Pt/C (10.6 %). We believe that the strategy demonstrated in this work can be extended to fabricate other multifunctional integrated electrocatalysts with high performance for hydrogen production. [ABSTRACT FROM AUTHOR]

Abstract: In this work, sludge-based activated carbon (SAC) was prepared from paper mill sewage sludge by physical activation with steam. The adsorption efficiency of SAC to cationic methylene blue (MB) and anionic reactive red 24 (RR 24) from aqueous solutions was investigated using fixed-bed adsorption column. The effects of influent dye concentration, particle size, adsorbent mass and flow rate on the breakthrough characteristics of the adsorption system were determined. Desorption of dyes on SAC was repeated for several cycles in HCl, NaOH and deionized water. The results showed that breakthrough time and exhaustion time increased with decreasing inlet dye concentration, particle size, flow rate and increasing adsorbent mass. The adsorption capacity of SAC in fixed-bed column was lower than that obtained from equilibrium study. However, the SAC adsorption performance was much better than commercial activated carbon, indicating the enormous potential of SAC for removing dyes. In addition, the lower desorption rate of MB than of RR 24 demonstrated that cationic dye was more stable on SAC. [Copyright &y& Elsevier]

Energy band location and charge separation mechanism of SnS 2 /Au/g-C 3 N 4 system during photoreduction under sunlight irradiation. • The catalyst is prepared by facile thermal treatment and chemical deposition method. • The SnS 2 /Au/g-C 3 N 4 composites show a superior optical adsorption under UV–vis light. • The Au nanoparticle and the Z-type scheme jointly improve the separation of carrier. • The SnS 2 /3ml-Au/g-C 3 N 4 displays the best photoreduction activity and durability. The use of semiconductor photocatalytic reduction technology has higher efficiency and lower energy consumption for CO 2 reduction, but its existence of some mismatched energy band positions and relatively slow charge-hole separation greatly limits its practical application. In this paper, a SnS 2 /Au/g-C 3 N 4 embedded structure model with carbon and nitrogen hybridization is proposed to gain an in-depth understanding of the role of hybridization and precious metal modification in photocatalysis. Carriers were investigated from the perspective of kinetics through photocurrent, LSV curve, and FL spectroscopy. After modification of Au nanoparticles, the photo-excited electrons showed a slower decay process, indicating that the separation of carriers was enhanced, which was further confirmed by impedance and PL spectroscopy. SEM, AFM and TEM analysis confirmed that the 2D face-to-face SnS 2 /Au/g-C 3 N 4 embedded structure was successfully prepared and the Au nanoparticles were evenly distributed. Au nanoparticles not only act as a bridge for electron transport in 2D semiconductor materials to accelerate electron transport, but generate more excited electrons by themselves under the radiation of sunlight, which effectively improves the separation efficiency of electron-hole pairs and enhances the photocatalyst activity. DFT calculations show that the Z-type mechanism and the intercalated energy level of the SnS 2 /Au/g-C 3 N 4 embedded structure expand the light absorption and improve the carrier separation efficiency. As expected, the photocatalyst activity with CO and CH 4 the evolution rate of up 93.81 µmol·g−1·h−1 and 74.98 µmol·g−1·h−1 under visible light irradiation, respectively, while the photocatalytic activity is negligible loss after 30 h photoreduction. This work reveals the role of embedded structure and precious metal modification in the separation and transmission of electron-hole, opening up new perspective for achieving high-efficiency solar CO 2 reduction performance. [ABSTRACT FROM AUTHOR]