Conjugated porous polymers (CPPs) with donor-it-acceptor (D-it-A) architectures can effectively modulate their electronic structures and promote the separation of photogenerated charge carriers by incorporating suitable it-bridging units, making them promising materials for efficient photocatalysis. In this study, we synthesized two well-defined D-it-A type CPP photocatalysts, TxEdSo and TxThSo, employing truxene as the electron donor and dibenzothiophene-S, S-dioxide (BTDO) as the acceptor, with 3,4-ethylenedioxythiophene (EDOT) and thiophene serving as the it-bridging units, respectively. The effects of these different linkers on photocatalytic hydrogen production (PHP) activity were systematically investigated. Compared with TxThSo using thiophene as the linking unit, TxEdSo with EDOT linking unit has a broader visible light absorption and effective charge separation ability, which facilitates the transport of charge along the polymer backbone. It exhibited a significant photocatalytic hydrogen evolution rate (HER) of 27.12 mmol g-1h- 1 under visible light. After loading 0.5 wt% Pt co-catalyst, the HER activity was further increased to 61.93 mmol g-1h- 1. In CPPs, incorporating the more electron-donating EDOT as the it-bridge unit, compared to polymers using thiophene as the linker, not only enhances the separation and transport efficiency of photogenerated charge carriers but also broadens the visible light absorption range, thereby significantly improving photocatalytic performance, especially in the PHP reaction.

The construction of heterojunction photocatalysts is one of the key strategies for achieving efficient and clean conversion of CO2. However, the energy conversion efficiency of traditional photocatalysts is still limited by bottlenecks such as insufficient carrier mobility. To overcome this bottleneck, a hydrothermal/in situ growth synergistic strategy was adopted to construct a CdS/ZnIn2S4 S-scheme heterojunction at the interface, forming M-S-M' interface bonding via Cd-S-In bridges to improve carrier transfer efficiency and CO2 conversion performance. The CO2 reduction performance of this heterojunction reached 270.6 mu mol g(-1) h(-1). This remarkable activity is attributed to the formation of Cd-S-In bonds, which create efficient electron transfer channels, thereby significantly facilitating charge separation and migration. The existence of these interfacial bonds was unequivocally confirmed by comprehensive characterization and density of states (DOS) analysis. The continuous electron transport channels formed by these Cd-S-In bridges not only accelerate carrier migration but also promote the formation of *COOH reaction intermediates, enabling efficient CO production. This work provides an effective strategy for improving heterojunction catalysts for CO2 reduction.

The efficient utilization of solar energy to convert carbon dioxide into renewable fuels is a compelling strategy for mitigating carbon emissions and realizing sustainable chemical cycles. Herein, we report a Ni-modified oxygen-deficient TiO2 (Ni/TiO2-x) catalyst that achieves exceptionally high photothermal CO2 reduction performance under simulated solar irradiation without external heating, reaching a remarkable total production yield of 278.3 mmol & centerdot;g(-1)& centerdot;h(-1). Structural and spectroscopic analyses reveal that the asymmetric Ni-V-O-Ti interfacial configuration serves as a unique charge polarization center that redistributes charge density and stabilizes reaction intermediates under light-induced thermal excitation. This asymmetric coordination disrupts the electronic degeneracy of the Ti & horbar;O framework, thereby lowering the free energy barrier for the rate-determining step. Density functional theory (DFT) calculations further demonstrate that the asymmetric site acts as a dual-function photothermal antenna, where light absorption and heat localization cooperate to accelerate H-2 activation and C & horbar;O bond cleavage. This work unveils a paradigm in which geometric asymmetry governs both charge transfer and localized heat management, providing a molecular-level blueprint for next-generation photothermal catalysts for solar-driven CO2 conversion.

Photocatalytic H2 O2 production from H2 O and O2 offers a sustainable route but is hindered by the limitations of single-component catalysts, such as narrow light absorption and rapid charge recombination. To address this, an organic/inorganic composite S-scheme heterojunction is constructed through the in-situ growth of In2 S3 nanosheets on a covalent organic framework (COF), synergistically enhancing light harvesting, carrier separation, and redox capacity. In-situ irradiated XPS, femtosecond transient absorption (fs-TA) spectroscopy, and density functional theory (DFT) calculations jointly reveal the charge transfer dynamics of the COF/In2 S3 composite. As a result, the optimized S-scheme heterojunction achieves a remarkable H2 O2 production rate of 5713.2 }mol g-1 h-1 in pure water. This work advances the design of S-scheme heterojunction design for optimizing COF-based photocatalysts and deepens the understanding of molecular energy-level engineering. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Photocatalytic nitrogen fixation technology has great potential in reducing the use of fossil fuels and mitigating environmental pollution, but low light energy utilization, limited active sites and easy complexation of carriers are still the primarily constraints on the catalytic performance. Herein, PMoV and Ag were attached to the W18O49 surface by electrostatic self-assembly and photodeposition. Ag/W18O49/PMoV Z-scheme heterojunction with double LSPR effect was successfully fabricated and used in photocatalytic nitrogen fixation. The experimental data indicated that W18O49 was able to absorb the photogenerated electrons injected by PMoV and Ag. The injected photogenerated electrons enriched the electron density at the OVs of the W18O49 surface, thus maintaining the plasmonic effect of W18O49. The fluorescence lifetimes of the photogenerated carriers in Ag/ W18O49/PMoV were extended, and the loading of Ag and PMoV provided new channels for the migration of photogenerated electrons and holes in Ag/W18O49/PMoV, which facilitated the catalytic reaction. The rate of photocatalytic ammonia synthesis by W18O49 was 32.9 mu mol g- 1h-1. The nitrogen fixation activity of the ternary Ag/W18O49/PMoV heterojunction catalyst was enhanced, and the ammonia production rate reached 118.4 mu mol g- 1h-1, which was 3.6 times of the W18O49 yield. The synergy between the electron-hole pairs with strong redox capable retained by the Z-scheme heterojunction and the energetic hot electrons formed by the LSPR effect effectively enhanced the catalytic activity of the catalyst. The study provided new insights into the design of Zschemem plasmonic heterostructures to generate high energy hot electrons to realize an efficient photocatalytic N2 reduction system.

Coupling H2O2 production with organic pollutant degradation can effectively overcome the sluggish kinetics of water oxidation while concurrently addressing environmental pollution challenges. In this work, an S-defect-rich ZnIn2S4/g-C3N4 (ZIS1-x/UCN) S-scheme heterojunction photocatalyst was constructed by in situ growing ZIS1-x nanosheets on porous ultrathin UCN. The designed ZIS1-x/UCN photocatalyst demonstrates enhanced visible light absorption, abundant active sites, and intimate interfacial contact. The optimized ZIS1-x/UCN-1.0 photo-catalyst exhibits outstanding dual functionality, simultaneously achieving an H2O2 production rate of 2902.2 mu mol g-1 h-1 and 91.3 % tetracycline (50 mg L-1) degradation efficiency. This H2O2 performance represents a 1.63-fold enhancement compared to its activity in pure water (1777.0 mu mol g-1 h-1). Through comprehensive characterization including femtosecond transient absorption spectroscopy (fs-TAS), in situ irradiation X-ray photoelectron spectroscopy (ISI-XPS), and in situ X-ray absorption fine structure spectroscopy (XAFS), we unequivocally confirm the S-scheme charge transfer mechanism. This S-scheme induced unique electronic structure not only fosters ultrafast electron transfer at the interface (3.54 ps) but also significantly enhances the redox capacity of photogenerated carriers. Collectively, this work opens new avenues for the dual application of photocatalytic technology in both energy production and environmental remediation.

With the intensification of the greenhouse effect, the catalytic conversion of CO2 has emerged as a critical challenge. Photothermal catalytic CO2 conversion into value-added products offers a promising strategy to mitigate CO2 emissions. In this study, a carbon-based catalyst loaded with metallic nickel is developed for efficient photothermal reduction of CO2 to CO. Potassium (K) modification is further introduced by tuning the K doping content, and the optimized catalyst exhibits exceptional CO selectivity (approximate to 100%) and photothermal activity (266 mmol g-1 h-1). Mechanistic investigations reveal that K modification significantly enhances CO2 adsorption capacity and modulates electron transfer pathways, as supported by DFT calculations. The synergistic effect of K modification in promoting CO2 activation and electron-carrier interactions under photothermal conditions is demonstrated to be pivotal for driving the CO2 to CO conversion. This work clarifies the role of alkali metal modification in photo-thermal catalytic systems and establishes a structure-performance relationship guided by electron-interface engineering.

Cooperative coupling of photocatalytic hydrogen peroxide production with organic pollutants degradation has an expansive perspective in energy storage and environmental conservation.Herein,an S-scheme het-erojunction is constructed by hybridizing a 3D flower like Schiff-based covalent organic framework(COF)with a porous structure g-C3N4,and a comprehensive strategy is proposed to achieve efficient H2O2 pro-duction yield coupling highly Rhodamine B(RhB)degradation rate.The charge carrier transfer mechanism is validated by an in-situ X-ray photoelectron spectroscopy,the density functional theory calculation,and a femtosecond transient absorption spectroscopy.Interestingly,the COF/g-C3N4 S-scheme heterojunction exhibits better charge separation efficiency compared to bare COF and pure g-C3N4,resulting in ameliora-tive photocatalytic activity.In addition,RhB is employed to consume photogenerated holes.Remarkably,2307 μmol g-1 h-1 H2O2 achieved over 10％-COF/g-C3N4 composite in RhB solution and O2 atmosphere,and 100％-RhB degradation rate obtained at 45 min.This work improves a facile strategy to ameliorate Schiff COF-based S-scheme heterojunction for efficient H2O2 production with full hole-electron utilization ability.

Cooperative coupling of photocatalytic hydrogen peroxide production with organic pollutants degradation has an expansive perspective in energy storage and environmental conservation. Herein, an S-scheme heterojunction is constructed by hybridizing a 3D flower like Schiff-based covalent organic framework (COF) with a porous structure g-C3 N4 , and a comprehensive strategy is proposed to achieve efficient H2 O2 production yield coupling highly Rhodamine B (RhB) degradation rate. The charge carrier transfer mechanism is validated by an in-situ X-ray photoelectron spectroscopy, the density functional theory calculation, and a femtosecond transient absorption spectroscopy. Interestingly, the COF/g-C3 N4 S-scheme heterojunction exhibits better charge separation efficiency compared to bare COF and pure g-C3 N4 , resulting in ameliorative photocatalytic activity. In addition, RhB is employed to consume photogenerated holes. Remarkably, 2307 mu mol g-1 h-1 H2 O2 achieved over 10 %-COF/g-C3 N4 composite in RhB solution and O2 atmosphere, and 100 %-RhB degradation rate obtained at 45 min. This work improves a facile strategy to ameliorate Schiff COF-based S-scheme heterojunction for efficient H2 O2 production with full hole-electron utilization ability. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

S-scheme photocatalyst has found widespread application in photocatalysis distinguished by its unique charge transfer pathway and excellent catalytic redox capability. Herein, a TiO2/CdIn2S4 (TCIS) heterojunction is constructed for efficient photocatalytic hydrogen peroxide production using Rhodamine B (RhB) sensitization via an S-scheme charge transfer mechanism. The optimized TCIS achieves a maximum H2O2 production rate of 2848 mu mol center dot g- 1 center dot h- 1 under visible light, with an apparent quantum yield of 4.63 % at 420 nm monochromatic light irradiation. This performance surpasses that using ethanol as a sacrificial agent by about 7.8-fold. Experimental results demonstrate that RhB broadens the spectrum response range owing to the dye sensitization, acts as holes trapping agent and provides H+ during photocatalysis. Therefore, improving the H2O2 production yield. In addition, in situ irradiated XPS, femtosecond transient absorption spectroscopy, and DFT calculations collectively elucidate the S-scheme charge transfer dynamics in the TiO2/CdIn2S4 heterojunction. This work provides a protocol for designing an S-scheme heterojunction with ameliorative photocatalytic performance for efficient H2O2 production by organic dye sensitization.

The photocatalytic activity of g-C3N4 can be enhanced through precise defect engineering. In this study, hierarchical porous g–C3N4–containing cyano groups and N vacancies was synthesized by thermally polymerizing dicyandiamide precursor in a hydrochloric acid solution of magnesium chloride. The resulting structure comprised crosslinked rod-shaped units with a high aspect ratio, facilitating efficient light transmission and absorption within the material. Furthermore, introducing N defects reduced the bandgap and optimized the electronic structure, thereby enhancing light absorption and exposing active sites effectively. The synergistic effects of N defects and the hierarchical porous structure disrupted the original electronic distribution of g-C3N4, leading to directional separation of photogenerated charge carriers and considerably enhancing hydrogen evolution performance. Consequently, the optimized hpCNX-0.05 sample exhibited markedly improved hydrogen evolution rates, achieving 1703.67 μmol g−1 h−1 under visible light irradiation, approximately 3.16 times higher than that of bulk g-C3N4. Overall, this paper presents a promising strategy for synthesizing hierarchical porous g-C3N4 with N defects to achieve highly efficient H2 production.

The photocatalytic activity of g-C3N4 3 N 4 can be enhanced through precise defect engineering. In this study, hierarchical porous g-C3N4-containing 3 N 4 -containing cyano groups and N vacancies was synthesized by thermally polymerizing dicyandiamide precursor in a hydrochloric acid solution of magnesium chloride. The resulting structure comprised crosslinked rod-shaped units with a high aspect ratio, facilitating efficient light transmission and absorption within the material. Furthermore, introducing N defects reduced the bandgap and optimized the electronic structure, thereby enhancing light absorption and exposing active sites effectively. The synergistic effects of N defects and the hierarchical porous structure disrupted the original electronic distribution of g-C3N4, 3 N 4 , leading to directional separation of photogenerated charge carriers and considerably enhancing hydrogen evolution performance. Consequently, the optimized hpCNX-0.05 X-0.05 sample exhibited markedly improved hydrogen evolution rates, achieving 1703.67 mu mol g1 h- 1 under visible light irradiation, approximately 3.16 times higher than that of bulk g-C3N4. 3 N 4 . Overall, this paper presents a promising strategy for synthesizing hierarchical porous gC3N4 3 N 4 with N defects to achieve highly efficient H2 2 production.

The conversion of CO2 into solar fuels via photo-driven catalytic reduction presents a promising avenue toward achieving carbon neutrality. Herein, copper-based catalysts are prepared and explored for photo-driven photothermal CO2 reduction reaction. The optimized catalyst exhibits a consistent CO production rate of 165.9mmolg-1 h-1 and 100% CO selectivity at ambient pressure. We unveil the intricate adsorption dynamics at play: H2 molecules predominantly interact with and activate at Cu sites, while CO2 molecules preferentially adsorb and activate at interfacial sites within the composites. Furthermore, we elucidate how the positive shift of the d-band center (εd) for Cu 3d orbitals significantly enhances H2 adsorption and activation. Crucially, the subsequent dissociation of H2 molecules at Cu sites drives the efficient conversion of adsorbed CO2 molecules at interfacial sites into CO. Overall, our findings not only advance the theoretical understanding but also offer practical insights for realizing photothermal catalytic CO2 reduction reactions.

Artificial photosynthesis offers a promising strategy for converting solar energy into environmental-friendly H2O2. Herein, robust photocatalytic H2O2 production through dioxygen reduction is achieved, reaching a high H2O2 yield of 873 μmol L−1 h−1. The photocatalyst was prepared by in-situ chemical vapor deposition of N, S co-doped graphene on TiO2 nanofibers. Thanks to the intimate interface with large area and Schottky junction, the H2O2 yield of the composite can be increased by eight times than that of pristine TiO2. Experimental results and density functional theory calculations clarify that the strong synergistic effect between the doped N and S atoms provides abundant active sites to facilitate the electron transfer, promote the adsorption of O2 molecules, and restrain the decomposition of formed H2O2 by suppressing H2O2 adsorption. This work not only provides a novel approach to build close contact between photocatalyst and co-catalyst, but also develops a highly efficient photocatalyst for H2O2 production.

Preparation of efficient photocatalysts with ease of recovery in solar fuel generation is highly desired to achieve carbon neutralization in carbon dioxide (CO2) emissions. Inspired from the forest with superior light penetration and fast gas transport, a TiO2/g-C3N4 composite nanowire arrays (NAs) film with maximized light utilization is devised. It is achieved by in-situ coating a thin layer of g-C3N4 (as the leaf) on the vertically-oriented TiO2 arrays (as tree trunks) on Ti foil (as soil). Benefiting from the effective charge separation by S-scheme charge transfer, intimate contact by the in-situ growth as well as the ingenious structure, the composite, readily recyclable, displays exciting performance in photocatalytic CO2 reduction. It is beyond doubt that the combination of heterojunction construction and “nature-inspired biomimetic photocatalyst” design promises practical applications and industrial use.

Photocatalytic CO2 conversion efficiency is hampered by the rapid recombination of photogenerated charge carriers. It is effective to suppress the recombination by constructing cocatalysts on photocatalysts with high-quality interfacial contact. Herein, we develop a novel strategy to in-situ grow ultrathin N-doped graphene (NG) layer on TiO2 hollow spheres (HS) with large area and intimate interfacial contact via a chemical vapor deposition (CVD). The optimized TiO2/NG HS nanocomposite achieves total CO2 conversion rates (the sum yield of CO, CH3OH and CH4) of 18.11 μmol g−1 h−1, which is about 4.6 times higher than blank TiO2 HS. Experimental results demonstrate that intimate interfacial contact and abundant pyridinic N sites can effectively facilitate photogenerated charge carrier separation and transport, realizing enhanced photocatalytic CO2 reduction performance. In addition, this work provides an effective strategy for in-situ construction of graphene-based photocatalysts for highly efficient photocatalytic CO2 conversion.

Reasonable design of efficient hierarchical photocatalysts has gained significant attention. Herein, a step-scheme (S-scheme) core-shell TiO2@ZnIn2S4 heterojunction is designed for photocatalytic CO2 reduction. The optimized sample exhibits much higher CO2 photoreduction conversion rates (the sum yield of CO, CH3OH, and CH4) than the blank control, i.e., ZnIn2S4 and TiO2. The improved photocatalytic performance can be attributed to the inhibited recombination of photogenerated charge carriers induced by S-scheme heterojunction. The improvement is also attributed to the large specific surface areas and abundant active sites. Meanwhile, S-scheme photogenerated charge transfer mechanism is testified by in situ irradiated X-ray photoelectron spectroscopy, work function calculation, and electron paramagnetic resonance measurements. This work provides an effective strategy for designing highly efficient heterojunction photocatalysts for conversion of solar fuels.