In‐situ Platinum Plasmon Resonance Effect Prompt Titanium Dioxide Nanocube Photocatalytic Hydrogen Evolution

Abstract

Herein, Pt‐decorated TiO2 nanocube hierarchy structure (Pt‐TNCB) was fabricated by a facile solvothermal synthesis and in‐situ photodeposition strategy. The Pt‐TNCB exhibits an excellent solar‐driven photocatalytic hydrogen evolution rate (337.84 μmol h−1), which is about 37 times higher than that of TNCB (9.19 μmol h−1). Interestingly, its photocatalytic property is still superior to TNCB with post modification Pt (1 wt %) (208.11 μmol h−1). The introduction of Pt efficiently extends the photoresponse of the composite material from UV to visible light region, simultaneously boosting their solar‐driven photocatalytic performance, which attribute to the porous structure, the sub size TNCB, the SPR effect of Pt NPs and strong interaction of two components. In fact, Pt NPs can enhance collective oscillations on delocalized electrons, which is conducive to capture electrons and hinder the recombination of photogenerated electron‐hole pairs, leading to the longer lifetime of photogenerated charges. The fabrication of Pt‐TNCB photocatalyst with SPR effect may provide a promising method to improve visible‐light photocatalytic activities for traditional photocatalysts.

Property-governed performance of platinum-modified titania photocatalysts

“…In the case of platinum content, the contrary reports have been published, suggesting that smaller or larger amount is better (Hufschmidt et al, 2002). However, usually the optimal amount (Table 3) has been suggested, ranging from 0.06 to 2 wt%, e.g., (i) 1.5 wt% for methyl orange degradation under UV/vis (Hu et al, 2012); (ii) 0.025 wt% for degradation of dichloromethane under UV (Ma et al, 2011), (iii) 0.5 wt% for UV methanol dehydrogenation (Ahmed et al, 2014), (iv) 0.2 wt%, 1 wt% or 2 wt% for methanol dehydrogenation, depending on the titania type (Wang et al, 2018), (v) 0.1 wt% for phenol degradation under UV and vis irradiation (Zielinska-Jurek et al, 2019), (vi) 0.057 wt%, 0.3 wt% and 2 wt% for methanol dehydrogenation, depending on the method of Pt deposition (Senevirathna et al, 2006), (viii) 0.1 wt% for hydrogen generation from acetic acid under UV (Zheng et al, 2009), (ix) 0.5 wt% for hydrogen evolution under simulated solar radiation (Hu et al, 2019), (x) 1 wt% for selective hydrogenation of phenylacetylene to styrene under UV (Lian et al, 2020), and (xi) 0.2 wt% for UV synthesis of benzimidazoles (Shiraishi et al, 2010). Interestingly, it has been found that the reaction conditions (pH value), irradiation intensity, the type of titania, kind of tested compounds and their concentration are also decisive, influencing the optimal content of platinum (Hufschmidt et al, 2002;Ma et al, 2011).…”

“…Since then, huge number of papers have been published on UV-activity enhancement by NMs (Pichat et al, 1981;Pichat et al, 1982;Nishimoto et al, 1985;Jakob et al, 2003;Subramanian et al, 2003;Kowalska et al, 2008;Azri et al, 2014). For example, Hu et al proved that platinum hinders charge carriers' recombination by photoluminescence and transient fluorescence spectroscopy, resulting in longer lifetime of photogenerated charge carriers (Hu et al, 2019). Similarly, time-resolved microwave conductivity (TRMC) method was used to show the scavenging of photogenerated electrons by platinum (both originated from inorganic salts and Chini clusters) deposited on the titania surface, which correlates well with the enhanced photocatalytic activity for oxidative decomposition of phenol and rhodamine B (Kowalska et al, 2008), as exemplary presented in Figure 3.…”

Oxygen doped g‐C3N4 with nitrogen vacancy for enhanced photocatalytic hydrogen evolution

“…O dopant always possesses more powerful electron adsorption ability and elevates carrier separation without damage the stability of melon skeleton. The O dopant in g‐C 3 N 4 would form C−O−C and C = O bonds, which can construct an internal electric field by achieving higher valence‐electron densities around the O atoms than C and N atoms [19,20] . Apart from that, band gap could be narrowed via O dopant to enlarge optical adsorption ability and conduction band position could be negatively shifted for stronger reducibility for H 2 production.…”

Sulfur and Ti3+ co‐Doping of TiO2 Nanotubes Enhance Photocatalytic H2 Evolution Without the Use of Any co‐catalyst

“…Since the discovery of photocatalytic water splitting in 1972 using at itanium dioxide (TiO 2 )p hotoanode, [1] TiO 2 has attracted wide research interest as ap hotocatalyst in the fields of organic pollutant degradation and photocatalytic H 2 generation. [2][3][4][5] Titanium dioxide, as ap hotocatalyst, provides intrinsic advantages over other photocatalysts, such as ah igh chemical stability, low-cost, high abundance,low toxicity and high corrosion resistance. [6][7][8] However,T iO 2 carries also some drawbacks that limit its efficient application.…”