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This study details the rational design and synthesis of Cu 2 ZnSnS 4 (CZTS)-doped anatase (A) heterostructures, utilizing earth-abundant elements to enhance the efficiency of solar-driven water splitting. A one-step hydrothermal method was employed to fabricate a series of CZTS-A heterojunctions. As the concentration of titanium dioxide (TiO 2 ) varied, the morphology of CZTS shifted from floral patterns to sheet-like structures. The resulting CZTS-A heterostructures underwent comprehensive characterization through photoelectrochemical response assessments, optical measurements, and electrochemical impedance spectroscopy analyses. Detailed photoelectrochemical (PEC) investigations demonstrated notable enhancements in photocurrent density and incident photon-to-electron conversion efficiency (IPCE). Compared to pure anatase electrodes, the optimized CZTS-A heterostructures exhibited a seven-fold increase in photocurrent density and reached a hydrogen production efficiency of 1.1%. Additionally, the maximum H 2 production rate from these heterostructures was 11-times greater than that of pure anatase and 250-times higher than the original CZTS after 2 h of irradiation. These results underscore the enhanced PEC performance of CZTS-A heterostructures, highlighting their potential as highly efficient materials for solar water splitting. Integrating Cu 2 ZnSnS 4 nanoparticles (NPs) within TiO 2 (anatase) heterostructures implied new avenues for developing earth-abundant and cost-effective photocatalytic systems for renewable energy applications.

The development of efficient deep-blue emitters with thermally activated delayed fluorescence (TADF) properties is a highly significant but challenging task in the field of organic light-emitting diode (OLED) applications. Herein, we report the design and synthesis of two new 4,10-dimethyl-6H,12H-5,11-methanodibenzo[ b,f ][1,5]diazocine ( TB )-derived TADF emitters, TB-BP-DMAC and TB-DMAC , which feature distinct benzophenone ( BP )-derived acceptors but share the same dimethylacridin ( DMAC ) donors. Our comparative study reveals that the amide acceptor in TB-DMAC exhibits a significantly weaker electron-withdrawing ability in comparison to that of the typical benzophenone acceptor employed in TB-BP-DMAC . This disparity not only causes a noticeable blue shift in the emission from green to deep blue but also enhances the emission efficiency and the reverse intersystem crossing (RISC) process. As a result, TB-DMAC emits efficient deep-blue delay fluorescence with a photoluminescence quantum yield (PLQY) of 50.4% and a short lifetime of 2.28 μs in doped film. The doped and non-doped OLEDs based on TB-DMAC display efficient deep-blue electroluminescence with spectral peaks at 449 and 453 nm and maximum external quantum efficiencies (EQEs) of 6.1% and 5.7%, respectively. These findings indicate that substituted amide acceptors are a viable option for the design of high-performance deep-blue TADF materials.

Peroxyoxalate chemiluminescence (PO-CL) is one of the most popular cold light sources, yet the drawback of aggregation-caused quenching limits their use. Here, we report a new kind of efficient bifunctional emitter derived from salicylic acid, which not only exhibits typical aggregation-induced emission (AIE) character but also has the ability to catalyze the CL process under basic conditions based on base sensitivity. By taking advantage of these unique features, we successfully confine the CL process on the surface of solid bases and provide a high-contrast visualization of CL emission. This method allows most of the common basic salts like sodium carbonate to be invisible encryption information ink and PO-CL solution to be a decryption tool to visualize the hidden information. The current study opens up an appealing way for the development of multifunction CL emitters for information encryption and decryption applications.

Cerium element with a unique electric structure can be used to modify semiconductor photocatalysts to enhance their photocatalytic performances. In this work, Ce-doped TiO 2 (Ce/TiO 2 ) was successfully achieved using the sol-gel method. The structural characterization methods confirm that Ce was doped in the lattice of anatase TiO 2 , which led to a smaller grain size. The performance test results show that the Ce doped in anatase TiO 2 significantly enhances the charge transport efficiency and broadens the light absorption range, resulting in higher photocatalytic performance. The Ce/TiO 2 exhibited a photocurrent density of 10.9 μA/cm 2 at 1.0 V vs. Ag/AgCl, 2.5 times higher than that of pure TiO 2 (4.3 μA/cm 2 ) under AM 1.5 G light. The hydrogen (H 2 ) production rate of the Ce/TiO 2 was approximately 0.33 μmol/h/g, which is more than twice as much as that of the pure anatase TiO 2 (0.12 μmol/h/g). This work demonstrates the effect of Ce doping in the lattice of TiO 2 for enhanced photocatalytic hydrogen production.

In this work, a simple one-step hydrothermal method was employed to prepare the Ce-doped Fe 2 O 3 ordered nanorod arrays (CFT). The Ce doping successfully narrowed the band gap of Fe 2 O 3 , which improved the visible light absorption performance. In addition, with the help of Ce doping, the recombination of electron/hole pairs was significantly inhibited. The external voltage will make the performance of the Ce-doped sample better. Therefore, the Ce-doped Fe 2 O 3 has reached superior photoelectrochemical (PEC) performance with a high photocurrent density of 1.47 mA/cm 2 at 1.6 V vs. RHE (Reversible Hydrogen Electrode), which is 7.3 times higher than that of pristine Fe 2 O 3 nanorod arrays (FT). The Hydrogen (H 2 ) production from PEC water splitting of Fe 2 O 3 was highly improved by Ce doping to achieve an evolution rate of 21 μmol/cm 2 /h.

In this article, hierarchical porous carbon (HPC) with high surface area of 1604.9 m 2 /g is prepared by the pyrolysis of rubberwood sawdust using CaCO 3 as a hard template. The bio-oil pyrolyzed from the rubber sawdust, followed by the polymerization reaction to form resole phenolic resin, can be used as a carbon source to prepare HPC. The biomass-derived HPC shows a three-dimensionally interconnected morphology which can offer a continuous pathway for ionic transport. The symmetrical supercapacitors based on the as-prepared HPC were tested in 1.0 M tetraethylammonium tetrafluoroborate/propylene carbonate electrolyte. The results of electrochemical analysis show that the HPC-based supercapacitor exhibits a high specific capacitance of 113.3 F/g at 0.5 A/g with superior rate capability and cycling stability up to 5000 cycles. Hybrid lithium-ion capacitors (LICs) based on the HPC and Li 4 Ti 5 O 12 (LTO) were also fabricated. The LICs have a maximum energy density of 113.3 Wh/kg at a power density of 281 W/kg. Moreover, the LIC also displays a remarkable cycling performance with a retention of 92.8% after 3000 cycles at a large current density of 0.75 A/g, suggesting great potential application in the energy storage of the LIC.

Carbon-coated Li 4 Ti 5 O 12 (LTO) has been prepared using polyimide (PI) as a carbon source via the thermal imidization of polyamic acid (PAA) followed by a carbonization process. In this study, the PI with different structures based on pyromellitic dianhydride (PMDA), 4,4'-oxydianiline (ODA), and p -phenylenediamine ( p -PDA) moieties have been synthesized. The effect of the PI structure on the electrochemical performance of the carbon-coated LTO has been investigated. The results indicate that the molecular arrangement of PI can be improved when the rigid p -PDA units are introduced into the PI backbone. The carbons derived from the p -PDA-based PI show a more regular graphite structure with fewer defects and higher conductivity. As a result, the carbon-coated LTO exhibits a better rate performance with a discharge capacity of 137.5 mAh/g at 20 C, which is almost 1.5 times larger than that of bare LTO (94.4 mAh/g).