Supplementary document for Development of a multi-needle fiberoptic Raman spectroscopy technique for simultaneous multi-site deep tissue Raman measurements in brain - 6537166.pdf

Supplemental Documen

Mesoporous TiO₂ Nanocrystals Grown in Situ on Graphene Aerogels for High Photocatalysis and Lithium-Ion Batteries

TiO₂/graphene composites have been well studied as a solar light photocatalysts and electrode materials for lithium-ion batteries (LIBs). Recent reports have shown that ultralight 3D-graphene aerogels (GAs) can better adsorb organic pollutants and can provide multidimensional electron transport pathways, implying a significant potential application for photocatalysis and LIBs. Here, we report a simple one-step hydrothermal method toward in situ growth of ultradispersed mesoporous TiO₂ nanocrystals with (001) facets on GAs. This method uses glucose as the dispersant and linker owing to its hierarchically porous structure and a high surface area. The TiO₂/GAs reported here exhibit a highly recyclable photocatalytic activity for methyl orange pollutant and a high specific capacity in LIBs. The strong interaction between TiO₂ and GAs, the facet characteristics, the high electrical conductivity, and the three-dimensional hierarchically porous structure of these composites results in highly active photocatalysis, a high rate capability, and stable cycling

Nickel Boride Cocatalyst Boosting Efficient Photocatalytic Hydrogen Evolution Reaction

Noble metals have been extensively used as catalyst promoters to driven highly efficient photocatalytic hydrogen evolution reaction (HER). However, noble-metal-based promoters are limited by their expensive costs and scarcities. Recently, massive efforts have been focused on metal phosphides, metal sulfides, and metal carbides as cocatalysts to achieve high HER performance. Currently, metal borides were reported as promoters for hydrogen evolution. Here, we demonstrate amorphous nickel boride (NiB) with a suitable band gap prepared by the chemical reduction of nickel nitrate hexahydrate using sodium borohydride as a cocatalyst over graphite carbon nitride (C3N4), thus achieving higher hydrogen evolution performance than C3N4. With the B­(δ−)–Ni­(δ+)–N­(δ−) bonds between NiB and C3N4, the as-prepared C3N4/NiB7.5 shows a dramatically enhanced photocatalytic hydrogen generation rate (464.4 μmol h–1 g–1), and reaches a quantum efficiency of 10.92% with 365 nm light irradiation

Rational Design of a Unique Ternary Structure for Highly Photocatalytic Nitrobenzene Reduction

The rational design and controllable synthesis of TiO₂ and noble metal composite photocatalysts represent an unprecedented challenge for developing the solar-driven reduction of nitrobenzene (NB) to aminobenzene (AB), owing to the recombination over the interface between the noble metals and TiO₂, which is harmful to the conversion efficiency of NB to AB. Here, we design a unique ternary structure (the high separation of TiO₂ and Pt nanoparticles on the surface of reduced graphene oxide (RGO)) through the sol–gel and microwave-assisted strategies. The substrate of RGO can be used as an “electric wire” to effectively transfer the photogenerated electrons from the isolated TiO₂ nanocrystals to the isolated Pt nanoparticles, which greatly decreases the interface recombination between TiO₂ and Pt and further improves the conversion efficiency of NB to AB under the solar light irradiation. We anticipate our research provides a new way to overcome the interface recombination on the binary photocatalysts in the photocatalytic reaction

Order–Disorder Engineering of Carbon Nitride for Photocatalytic H₂O₂ Generation Coupled with Pollutant Removal

Highly crystalline carbon nitride (CCN), benefiting from the reduced structural imperfections, enables improved electron–hole separation. Yet, the crystalline phase with insufficient inherent defects suffers from a poor performance toward the reaction intermediate adsorption with respect to the amorphous phase. Herein, a crystalline–amorphous carbon nitride (CACN) with an isotype structure was constructed via a two-step adjacent calcination strategy. Through specific oxygen etching and crystallization, the formation of a built-in electric field at the interface could drive charge transfer and separation, thus promoting photoredox reaction. As expected, the optimized CACN exhibited a H2O2 generation efficiency as high as 2.15 mM gcat–1 h–1, paired with a promoted pollutant degradation efficiency, which outperform its crystalline (CCN) and amorphous [amorphous carbon nitride (ACN)] counterparts. The detailed electron/hole transportation via a built-in electronic field and free radical formation based on the enhanced adsorption of oxygen were considered, and the synchronous reaction pathway was carried out. This work paves a novel pathway for the synthesis of carbon nitride with an isotype structure from the perspective of interfacial engineering

Trash to Treasure: Photoreforming of Plastic Waste into Commodity Chemicals and Hydrogen over MoS₂‑Tipped CdS Nanorods

Plastic valorization presents a significantly untapped opportunity to address environmental issues while creating the necessary economic push for a circular carbon economy. Compared with the conventional routes for processing plastics (e.g., pyrolysis and gasification), a photoreforming strategy, namely, photocatalytic plastic oxidation paired with water splitting, aims to achieve plastic valorization into commodity chemicals under mild conditions while offering hydrogen fuels. Here, we implement MoS2-tipped CdS nanorod photocatalysts in an aqueous medium to reform pretreated plastics that range from polyesters (e.g., polylactic acid (PLA) and polyethylene terephthalate (PET)) to polyolefins (e.g., polyethylene (PE)). The architecture of MoS2/CdS takes advantage of the anisotropic morphology and rapid charge transfer features of nanorods, by collecting the electrons at the MoS2 tip for hydrogen evolution and utilizing the entire sidewall of CdS nanorods with rich holes toward plastic oxidation. It is shown that continuous H2 can be evolved from photoreforming of PLA, PET (commercial PET granules and real-world PET bottles), and PE, while these plastic substrates are accordingly converted into a series of valuable chemicals. This work provides an effective way to harness solar energy to realize the transformation of trash (plastics) to treasure (gaseous/liquid chemicals)