A full-spectrum photocatalyst with strong near-infrared photoactivity derived from synergy of nano-heterostructured Er3+-doped multi-phase oxides

Efficient wide-spectrum one-dimensional MWO4 (M = Mn, Co, and Cd) photocatalysts: Synthesis, characterization and density functional theory study

Broadening the absorption region to near-infrared (NIR) light is critical for the photocatalysis due to the larger proportion and stronger penetration of NIR light in solar energy. In the present paper, one-dimensional (1D) MWO4 (M = Mn, Co, and Cd) materials synthesized by electrospinning technique, were studied by combining the density functional theory (DFT) with experiment results, which possessed the enhanced light absorption capability within the range of 200-2000 nm. It was proved that in the ultraviolet-visible (UV-Vis) region, the absorption bands of CoWO4 and MnWO4 samples were attributed to the metal-to-metal charge transfer mechanism, while the absorption of CdWO4 sample may be referable to the ligand-to-metal charge transfer mechanism. In the near-infrared (NIR) region, the absorption of CoWO4 and MnWO4 primarily originated from the d-d orbital transitions of Mn2+ and Co2+. The photocatalytic experimental results showed that the degradation rates for bisphenol A (BPA) over CoWO4, MnWO4, and CdWO4 photocatalysts under UV-Vis/NIR light irradiation for 140 min/12 h were 78.8 %/75.9 %, 23.8 %/21.3 %, 12.8 %/8.7 %, respectively. This research offers the novel insights into the precise construction of tungstate catalytic systems and contributes to the advancement of UV-Vis-NIR full spectrum photocatalytic technology, and lays a foundation for a cleaner and more environmental-friendly future.

Near-Infrared-Driven Photocatalysts: Design, Construction, and Applications

Photocatalysts, which utilize solar energy to catalyze the oxidation or reduction half reactions, have attracted tremendous interest due to their great potential in addressing increasingly severe global energy and environmental issues. Solar energy utilization plays an important role in determining photocatalytic efficiencies. In the past few decades, many studies have been done to promote photocatalytic efficiencies via extending the absorption of solar energy into near-infrared (NIR) light. This Review comprehensively summarizes the recent progress in NIR-driven photocatalysts, including the strategies to harvest NIR photons and corresponding photocatalytic applications such as the degradation of organic pollutants, water disinfection, water splitting for H₂ and O₂ evolution, CO₂ reduction, etc. The application of NIR-active photocatalysts employed as electrocatalysts is also presented. The subject matter of this Review is designed to present the relationship between material structure and material optical properties as well as the advantage of material modification in photocatalytic reactions. It paves the way for future material design in solar energy-related fields and other energy conversion and storage fields.

Recent Progress, Challenges, and Prospects in Two-Dimensional Photo-Catalyst Materials and Environmental Remediation

The successful photo-catalyst library gives significant information on feature that affects photo-catalytic performance and proposes new materials. Competency is considerably significant to form multi-functional photo-catalysts with flexible characteristics. Since recently, two-dimensional materials (2DMs) gained much attention from researchers, due to their unique thickness-dependent uses, mainly for photo-catalytic, outstanding chemical and physical properties. Photo-catalytic water splitting and hydrogen (H2) evolution by plentiful compounds as electron (e-) donors is estimated to participate in constructing clean method for solar H2-formation. Heterogeneous photo-catalysis received much research attention caused by their applications to tackle numerous energy and environmental issues. This broad review explains progress regarding 2DMs, significance in structure, and catalytic results. We will discuss in detail current progresses of approaches for adjusting 2DMs-based photo-catalysts to assess their photo-activity including doping, hetero-structure scheme, and functional formation assembly. Suggested plans, e.g., doping and sensitization of semiconducting 2DMs, increasing electrical conductance, improving catalytic active sites, strengthening interface coupling in semiconductors (SCs) 2DMs, forming nano-structures, building multi-junction nano-composites, increasing photo-stability of SCs, and using combined results of adapted approaches, are summed up. Hence, to further improve 2DMs photo-catalyst properties, hetero-structure design-based 2DMs' photo-catalyst basic mechanism is also reviewed.

Enhanced visible light-active CeO2/CuO/Ag2CrO4 ternary heterostructures based on CeO2/CuO nanofiber heterojunctions for the simultaneous degradation of a binary mixture of dyes

CeO₂/CuO/Ag₂CrO₄ composite is fabricated using an electrospinning and precipitation. Also, composite can photodegrade RB and MB under visible light irradiation. CeO₂/CuO/Ag₂CrO₄ can enhanced photocatalytic activity due to formed heterojunction.

Challenges and implication of full solar spectrum-driven photocatalyst

Conventional metal oxide and its composites embrace the long-standing problem of using the combined visible and near-infrared (NIR) light. Doping with suitable impurities of metal, nonmetal, or its combinations for visible light enhancement is very well studied. However, the quantum efficiency of these photocatalysts does not produce an exciting appearance toward visible and NIR light when irradiated through either artificial or natural light. Furthermore, owing to the limited availability of solar light, challenges arise from the implication of these developed nano-photocatalysts. Therefore, the hybridized concept was developed for the effective use of either full or partial solar spectrum, even functioning in dark conditions. The present review focuses on the challenges of hybridized photocatalysts in storing and discharging the harvested photons obtained from the solar spectrum. The review vividly emphasizes the evolution of light-driven nanomaterials since its innovation and significant breakthroughs in brief, while a detailed presentation of the implications of hybrid photocatalysts for full solar applications, including the mechanistic features, charging-discharging characteristics, work function, charge carrier mobility, and interactions, follows. The article also delivers the substantial contribution of these materials in regard to energy and environmental application.

Full-Spectrum Photocatalytic Activity of ZnO/CuO/ZnFe2O4 Nanocomposite as a PhotoFenton-Like Catalyst

Deriving photocatalysts by the calcination of hydrotalcite-like compounds has attracted growing interest for extending their photocatalytic activity to the visible and even near-infrared (NIR) light regions. Herein, we describe the acquisition of a ZnO/CuO/ZnFe2O4 nanocomposite with good photoFenton-like catalytic activity under UV, visible and near-infrared (NIR) light irradiation by optimizing the calcination temperature of the coprecipitation product of Zn2+, Cu2+ and Fe3+. The ZnO/CuO/ZnFe2O4 nanocomposite is composed of symbiotic crystals of ZnO, CuO and ZnFe2O4, which enable the nanocomposite to show absorption in the UV, visible and NIR light regions and to produce a transient photocurrent in the presence of H2O2 under NIR irradiation. The full-spectrum photoFenton-like catalyst shows improved performance for the degradation of methyl orange with an increasing amount of H2O2 and is very stable in the recycling process. We believe that the ZnO/CuO/ZnFe2O4 nanocomposite is a promising full-spectrum photoFenton-like catalyst for the degradation of organic pollutants.

Visible-to-NIR Photon Harvesting: Progressive Engineering of Catalysts for Solar-Powered Environmental Purification and Fuel Production

Utilization of diffusive solar energy through photocatalytic processes for environmental purification and fuel production has long been pursued. However, efficient capture of visible-near-infrared (NIR) photons, especially for those with wavelengths longer than 600 nm, is a demanding quest in photocatalysis owing to their relatively low energy. In recent years, benefiting from the advances in photoactive material design, photocatalytic reaction system optimization, and new emerging mechanisms for long-wavelength photon activation, increasing numbers of studies on the harnessing of visible-NIR light for solar-to-chemical energy conversion have been reported. Here, the aim is to comprehensively summarize the progress in this area. The main strategies of the long-wavelength visible-NIR photon capture and the explicitly engineered material systems, i.e., narrow optical gap, photosensitizers, upconversion, and photothermal materials, are elaborated. In addition, the advances in long-wavelength light-driven photo- and photothermal-catalytic environmental remediation and fuel production are discussed. It is anticipated that this review presents the forefront achievements in visible-NIR photon capture and at the same time promotes the development of novel visible-NIR photon harnessing catalysts toward efficient solar energy utilization.