Nanostructured Antimony‐Doped Tin Oxide Layers with Tunable Pore Architectures as Versatile Transparent Current Collectors for Biophotovoltaics

Abstract

Nanostructured transparent conducting oxide (TCO) layers gain increasing importance as high surface area electrodes enabling incorporation of functional redox species with high loading. The fabrication of porous TCO films, namely, antimony‐doped tin oxide (ATO), is reported using the self‐assembly of preformed ATO nanocrystals with poly(ethylene oxide‐b‐hexyl acrylate) (PEO‐b‐PHA) block copolymer. The high molar mass of the polymer and tunable solution processing conditions enable the fabrication of TCO electrodes with pore sizes ranging from mesopores to macropores. Particularly notable is access to uniform macroporous films with a nominal pore size of around 80 nm, which is difficult to obtain by other techniques. The combination of tunable porosity with a large conducting interface makes the obtained layers versatile current collectors with adjustable performance. While all the obtained electrodes incorporate a large amount of small redox molecules such as molybdenum polyoxometalate, only the electrodes with sufficiently large macropores are able to accommodate high amounts of bulky photoactive photosystem I (PSI) protein complexes. The 11‐fold enhancement of the current response of PSI modified macroporous ATO electrodes compared to PSI on planar indium tin oxide (ITO), makes this type of electrodes promising candidates for the development of biohybrid devices.

Full Gamut Wall Tunability from Persistent Micelle Templates via Ex Situ Hydrolysis

“…The general SEM and SAXS characteristics were largely similar to the in situ series, albeit with a lesser degree of ordering apparent by SEM ( Figures and and Figure S9, Supporting Information). This is consistent with recent examples of micelle assembly with preformed nanoparticles that generally result in rougher interfaces and a lesser degree of symmetry due to retention of the starting nanoparticle shape . The trends in SAXS d‐spacing were analyzed using the described log–log coordinate space (Figure a).…”

“…Efforts have led to wide ranging applications for porous nanomaterials arising from their novel electronic, catalytic, optical, and biological properties . There has been significant progress using the self‐assembly of block copolymers to realize well‐defined nanomaterials with a range of morphologies, compositions, and dimensions . Despite the widespread production and use of nanomaterials, there remains a need for “materials by design” approaches that support predictable and tailored architectures.…”

Robust electrografted interfaces on metal oxides for electrocatalysis – an in situ spectroelectrochemical study

“…39 ATO is highly conductive, transparent, resistant to corrosion, and has been used for many purposes including as conductive supports for electrocatalysis. [39][40][41][42][43][44] As evidenced by SEM (Scheme 1, for further magnifications see Fig. S2), the resulting crack-free me-ATO films are around 160 nm thick with an open, mesoporous structure throughout (pore size ~ 8 nm, as determined previously 39 ).…”

Cavitation-enabled rapid and tunable evolution of high-χN micelles as templates for ordered mesoporous oxides

“…[1][2][3][4][5][6][7][8][9][10] In all these examples, the size of the micelle largely influences the performance. Micelles have been widely employed for emulsions, drug delivery, nanoreactors, and soft-templates for inorganic nanoparticles.…”

“…[1][2][3][4][5][6][7][8][9][10] In all these examples, the size of the micelle largely influences the performance. 4 In this later example, high molar mass block copolymer micelles generated ∼80 nm macropores in antimony-doped tin oxide electrodes. For drug delivery, the micelles size determines both the loading capacity 11,12 as well as the capability to cross cell membranes.…”