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Photocatalytic CO2 reduction to solar fuels holds great promise for storing renewable energy and mitigating global warming. However, its widespread application is hindered by the low optical absorption and inefficient utilization of charge carriers. One prospective approach to enhance photocatalytic performance involves converting low-energy photons into thermal energy. In this work, we explore the utilization of the thermochromic effect to enhance the selectivity and activity of photocatalytic CO2 conversion, particularly in scenarios without photosensitizers and sacrificial agents. We have combined Mo-doped VO2 (M1V), a thermochromic material, with an InVO4 (IV) photocatalyst to enhance optical absorption and facilitate charge transfer in IV. The M1V-IV composite exhibits exceptional selectivity in solar-driven CO2 reduction, an excellent selectivity of 99% with a photothermal CO formation rate of 58.4 μmol h−1 g−1 in pure water under 330 mW cm−2 light irradiation. The CO evolution rate for M1V-IV is 1.5 times higher than that of the VO2–InVO4 composite and 6 times higher than that of pure IV. Comprehensive spectroscopic characterization and theoretical calculations disclose that the enhanced performance is attributed to the increased separation of charge carriers and the photocatalytic enhancement of CO2 reduction due to the thermal effect. We successfully propose a reaction mechanism for CO2 photoreduction on M1V-IV. This work introduces a novel strategy to enhance photocatalytic performance by leveraging the thermochromic effect in CO2 reduction. [ABSTRACT FROM AUTHOR]

Rational interphase reaction provides a feasible method to overcome the matters of insufficient adsorption of CO2 molecules at the catalytic sites and competitive hydrogen evolution reaction (HER), which can increase the formation rate and selectivity of carbon derivatives in photocatalytic CO2 reduction. Herein, a hydrophobic photocatalyst with TiO2 nanosheet arrays grown on hydrophobic carbon paper (TiO2‐HCP) is fabricated using a combination of magnetron sputtering and hydrothermal method, and its unique structure not only endows it excellent light absorption and effective carrier spatial separation but also avoids the hydrophobic reagent covering reactive sites. When the interphase reaction shifts from solid–liquid diphase to gas‐liquid‐solid tri‐phase, the photocatalytic CO2 reduction over TiO2‐HCP mainly generates CO molecules and effectively suppresses HER due to the HCP suppressing the mass transfer of H2O molecules to active sites. Notably, amounts of H2 byproduct can further react with CO2/CO to produce high value‐added CH4 resultant by modifying the N‐doped TiO2‐HCP with nickel/nickel oxide species. In the tri‐phase interfacial CO2 photoreduction system, the CH4 formation rate of Ni@N‐doped TiO2‐HCP reaches 134.17 µmol m−2 h−1 (about 74.6% selectivity) and total carbon derivatives selectivity is about 93%. [ABSTRACT FROM AUTHOR]

It is extraordinarily exigent to solve the efficiency of 6H+/6e− photoreduction of CO2 and H2O into methanol as the major product, which is limited by the severe photogenerated carrier recombination, the reoxidation of methanol at high temperature, and photocorrosion of catalysts. Herein, we developed an elaborate gas–liquid–solid system assembled by using a novel multicomponent SrTiO3 (La Cr)/Cu@Ni/SiO2/TiN (STO/Cu@Ni/SiO2/TiN) heterojunction, realizing a highly efficient and robust photocatalytic CO2 reduction to methanol at low temperature. STO/Cu@Ni/SiO2/TiN exhibits excellent light absorption and high charge carriers separation nature, and the evolution of methanol is 25.8 μmol (h gcat.)−1 roughly not only 173 folds higher than those observed compared with the STO counterpart, but also is 50 times that those of traditional gas–solid two-phase system. Of note, these improved performances are attributed to the enhancement of the local surface plasmonic resonance of Cu@Ni nanoparticles by changing the local medium dielectric constant and prolonged carrier's lifetime originating from heterostructure. Moreover, plasmonic TiN nanoparticles play an important role in remaining the triphase interfacial system temperature at 90 °C and increasing methanol production excellently. While, the ionic liquid in the gas–liquid–solid system can activate CO2 molecules, thereby greatly improves the yield of methanol. In situ Fourier transform infrared (FTIR) spectra and 13C isotope labeling tests reveal the reaction path of CO2 on the photocatalyst surface. This work may provide a new direction for the efficient photoreduction of CO2 to methanol. [ABSTRACT FROM AUTHOR]

From 1999, with the rapid expansion of enrollment scale, colleges have experienced fast development and construction of new campuses. However, the urgency of the demand for campus space at that time led to hie shortcomings of paying more attention to speed than connotation during the construction of the new campus. Even now the evaluation of new campuses which have been used for nearly twenty years and whether the space of new campuses has played its due role will affect the display of the heritage and temperament of colleges. This paper uses the typical spatial cognitive concept--spatial image to analyse the elements of spatial images on campuses, summarizes the perceptions of teachers and students towards the space of four new campuses in Chengdu through questionnaire survey and analysis, puts forward the principles of campus space design and the strategies of classification design, and intends to take spatial images as the research cut-in point to provide new ideas and suggestions for the design and improvement of campus space from the perspective of users. [ABSTRACT FROM AUTHOR]

Investigating kinetic mechanisms to design efficient photocatalysts is critical for improving photocatalytic CO 2 reduction, but the stochastic photo-physical/chemical properties of kinetics remain unclear. Herein, we propose a statistical study to discuss the stochastic feature evolution of photocatalytic systems. The uncertainties of light absorption, charge carrier migration, and surface reaction are described by nonparametric estimation methods in the proposed model, which includes the effect of operational and material parameters. The density distribution of surface electrons shifts from a skewed distribution to an approximate uniform distribution as incident photon density increases. The system temperature rising induces the rate-determining step of surface reactions to change from charge carrier kinetics to reactant activation processes. Benefiting from the synergistic optimization between the operational parameter and active site density, the electron-capturing probability of active sites is boosted from 0.06 to 0.17. The modified reaction kinetic equation is constructed based on the distribution function of charge carrier kinetics. Furthermore, the experimental photoactivity results are consistent with the statistical analysis, which proves the feasibility of the established model. The characterization tests show that the gap between testing activities and theoretical efficiency is caused by a mismatch between charge carrier supply and mass transfer. Our work unveils the stochastic features in photocatalytic CO 2 reduction, offering a comprehensive analytical framework for photocatalytic system optimization.