The development of smart and sustainable photocatalysts is in high priority for the synthesis of H2O2 because the global demand for H2O2 is sharply rising. Currently, the global market share for H2O2 is around 4 billion US$ and is expected to grow by about 5.2 billion US$ by 2026. Traditional synthesis of H2O2 via the anthraquinone method is associated with the generation of substantial chemical waste as well as the requirement of a high energy input. In this respect, the oxidative transformation of pure water is a sustainable solution to meet the global demand. In fact, several photocatalysts have been developed to achieve this chemistry. However, 97% of the water on our planet is seawater, and it contains 3.0–5.0% of salts. The presence of salts in water deactivates the existing photocatalysts, and therefore, the existing photocatalysts have rarely shown reactivity toward seawater. Considering this, a sustainable heterogeneous photocatalyst, derived from hydrolysis lignin, has been developed, showing an excellent reactivity toward generating H2O2 directly from seawater under air. In fact, in the presence of this catalyst, we have been able to achieve 4085 μM of H2O2. Expediently, the catalyst has shown longer durability and can be recycled more than five times to generate H2O2 from seawater. Finally, full characterizations of this smart photocatalyst and a detailed mechanism have been proposed on the basis of the experimental evidence and multiscale/level calculations.

In this work, we have fabricated an aryl amino-substituted graphitic carbon nitride (g-C 3 N 4 ) catalyst with atomically dispersed Mn capable of generating hydrogen peroxide (H 2 O 2 ) directly from seawater. This new catalyst exhibited excellent reactivity, obtaining up to 2230 μM H 2 O 2 in 7 h from alkaline water and up to 1800 μM from seawater under identical conditions. More importantly, the catalyst was quickly recovered for subsequent reuse without appreciable loss in performance. Interestingly, unlike the usual two-electron oxygen reduction reaction pathway, the generation of H 2 O 2 was through a less common two-electron water oxidation reaction (WOR) process in which both the direct and indirect WOR processes occurred; namely, photoinduced h + directly oxidized H 2 O to H 2 O 2 via a one-step 2e − WOR, and photoinduced h + first oxidized a hydroxide (OH − ) ion to generate a hydroxy radical ( • OH), and H 2 O 2 was formed indirectly by the combination of two • OH. We have characterized the material, at the catalytic sites, at the atomic level using electron paramagnetic resonance, X-ray absorption near edge structure, extended X-ray absorption fine structure, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, magic-angle spinning solid-state NMR spectroscopy, and multiscale molecular modeling, combining classical reactive molecular dynamics simulations and quantum chemistry calculations.

No abstract

An ultraviolet‐deposited MoO3 film is developed as anode interlayer based on molybdenum(V) chloride as precursor. The ultraviolet‐deposited MoO3 film is prepared from the precursor film (spin coated from its solution) with ultraviolet irradiation treatment, and the preparation process of the MoO3 film is facile, low cost, and compatible with mass production and flexible substrate. The composition of the MoO3 film is analyzed by X‐ray photoelectron spectroscopy. The work function as well as the surface morphology and wettability of indium tin oxide (ITO) modified by the MoO3 film are investigated by ultraviolet photoelectron spectroscopy, atomic force microscopy, and contact angle tester, respectively, where the analyses show the ITO modified by the MoO3 anode interlayer can offer excellent energy level alignment and interface contact with active layer. The photovoltaic performance of nonfullerene polymer solar cells (PSCs) based on the MoO3 anode interlayer is researched with typical and relatively low‐cost PBDB‐T:ITIC as active layer, and the ITO/MoO3‐based device shows the highest power conversion efficiency of 9.27% compared with the bare ITO‐based device (3.69%) and the ITO/PEDOT:PSS‐based device (9.15%). The results demonstrate the great potential of the ultraviolet‐deposited MoO3 film as anode interlayer for high‐performance PSCs.

No abstract