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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]

Foreigner element doping is one of effective strategies to promote photocatalytic reaction. Herein, a convenient one-step solvothermal method is applied to enable the isomorphic substitution of In3+ in In(OH) 3 by Bi3+. The composition and microstructure of the photocatalysts were mainly obtained by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). UV–Vis diffuse reflectance and photoluminescence (PL) spectroscopy revealed the optical properties of photocatalysts. The surface properties of photocatalysts were mainly characterized by X-ray photoelectron spectroscopy (XPS). Theoretical calculations were used to reveal the reaction mechanism. The results indicated that CO production rate and selectivity of Bi3+ doped In(OH) 3 are much higher than that of the pure In(OH) 3 , which could be attributed to the extended solar spectral response, the enhanced CO 2 adsorption capacity and the accelerated photogenerated carriers separation. The current work verifies the potential application of isomorphic substitution as an efficient route for solar fuel production. The incorporation of Bi atoms into In(OH) 3 lattice introduced many defects, which narrowed the band gap, extended the solar spectral response range, inhibited the recombination of photocarriers and exposed more active sites. As a result, much higher activity for CO 2 photoreduction toward CO with H 2 O is achieved. [Display omitted] • Bi3+ doped In(OH) 3 photocatalysts are fabricated via a one-pot solvothermal method. • Introduction of Bi3+ remarkably promotes specific surface area and formation of In vacancies. • Synergetic effects of Bi3+ and In vacancies improve light absorption and charge separation. • Bi3+ isomorphic substitution for In3+ enhances CO 2 reduction with improving CO selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plasmonic TiN nanoparticles are embedded into g-C 3 N 4 interlayers. • The optical absorption and carrier transfer ability of the composites are boosted. • The optimized catalyst has a good CO yield and stability. In CO 2 photocatalytic conversion, the development of efficient, stable, and inexpensive catalysts is a hot research topic. Herein, to improve the inherent shortcomings of pristine g-C 3 N 4 with high recombination rate and poor photocatalytic activity, non-noble plasmonic titanium nitride (TiN) nanoparticles are covered by g-C 3 N 4 nanosheets. The porous morphology of g-C 3 N 4 nanosheets greatly promotes the adsorption of CO 2 and remarkably increases the amount of surface active sites, thus laying a solid foundation for efficient CO 2 capture and conversion. Meanwhile, the decoration of TiN nanoparticles with localized surface plasmon resonance (LSPR) effects significantly broaden the spectral response range and strengthen the transfer of photogenerated charge carriers. The size of TiN nanoparticles is closely related to the catalytic performance. The optimized photocatalyst shows an enhanced CO yield of 210.5 μmol/g/h, which is 6.05 times and 2.77 times higher than those of the bulk and porous g-C 3 N 4 , and exhibits good stability during the reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • BiVO 4 @TiO 2 shows high selectivity and activity for CO 2 -to-CH 4 conversion. • S-scheme heterojunction was identified by DFT and KPFM. • Effective separation and directional migration of electrons are achieved. • Achieving efficient CO 2 conversion by reinforcing reaction process factors. • A solar-to-fuels efficiency of ∼ 0.46 ‰ is obtained under UV-enhanced light sources. Herein, a unique structure BiVO 4 @TiO 2 nanograss/needle arrays S-scheme heterojunction photocatalyst for CO 2 photoreduction reaction was created. The photocatalyst can drive electrons to the reactive spots spontaneously and continuously, which effectively tackles the problem of severe recombination and disordered migration of photogenerated carriers. Theoretical calculations and experimental results demonstrate that adding BMIM-BF 4 ionic liquid to generate BMIM-*CO 2 intermediate promotes CO 2 activation and enrichment of reactants concentration around the catalytic sites. Benefiting from the sufficient electron supply of catalytic sites and reinforced reactants supply in the interfacial microenvironment, the BiVO 4 @TiO 2 photocatalyst shows high selectivity and activity of CO 2 -to-CH 4 conversion. The CH 4 selectivity increased to 57.3 % (132.7 μmol m-2h−1) and the methanation activity was increased by 8.6 times in the 5.0 % BMIM-BF 4 aqueous solution. Significantly, the BiVO 4 @TiO 2 NNAs catalyst obtains a solar-to-fuels energy efficiency of ∼ 0.46 ‰ under ultraviolet-enhanced light sources without any sacrificial agent or co-catalyst. This work displays the relationship between reaction process factors (electron supply, CO 2 molecule, and proton supply) and CO 2 photoreduction activity and selectivity, giving new insight into achieving efficient CO 2 photoreduction conversion. [ABSTRACT FROM AUTHOR]

• A reactor design method for solar-driven photothermal conversion of CO 2 into fuels is proposed. • The whole chain from solar capturing, carrier transport, heat and mass transfer, and reaction kinetics is elucidated. • The effects of different factors on the photothermal catalytic reduction process of carbon dioxide are studied. • The energy flows and losses during the reduction process are quantitatively analyzed. Proper reactor design is of vital importance for highly-efficient photothermal catalytic CO 2 reduction into solar fuels. With respect to the whole chain from capturing solar energy through energy and mass transfer to the final reduction of CO 2 into fuels, this work proposes a systematic model of elaborately designing solar-driven photothermal catalytic reactors based on comprehensively studying the broadband light harvesting, energy and mass transport, and chemical conversion processes in the entire reduction of CO 2 by harnessing solar energy. The established numerical model including the optical and electrical simulations of the catalyst nanoparticle as well as the flow, thermal, and chemical reaction field in the reactor is developed to integrate the overall process of the photocatalytic CO 2 reduction, so as to analyze the effectiveness of the reactor and further obtain the optimal design strategy. Based on the analysis of the calculated results, methods are put forward to promote the chemical reaction by changing various parameters to regulate the light capture, radiation transfer, temperature field, and reactant supply in the catalyst layer. Most importantly, the designed reactor shows solar energy harnessing-conversion capability with remarkable light absorptivity, energy confinement, and reactants enrichment characteristics, thus realizing outstanding catalytic performance. This innovative reactor design strategy could greatly facilitate the solar-driven photothermal catalytic CO 2 reduction process. [ABSTRACT FROM AUTHOR]