Glucose-derived carbon materials with tailored properties as electrocatalysts for the oxygen reduction reaction

• Rafael Gomes Morais,
• Natalia Rey-Raap,
• José Luís Figueiredo and
• Manuel Fernando Ribeiro Pereira

Beilstein J. Nanotechnol. 2019, 10, 1089–1102, doi:10.3762/bjnano.10.109

• the response of the electrocatalyst towards the oxygen reduction reaction. Results and Discussion Effect of microporosity The nitrogen adsorption–desorption isotherms and the pore size distributions obtained by applying the quenched solid density functional theory (QSDFT) are presented in Figure 1a

• between the carbon material and the activating agent results in materials with a more developed microporosity. In addition, the pore size of the samples is also broadened by increasing the contact time (Figure 1b). The reaction occurring during the physical activation of the samples removes carbon atoms

• Warburg impedance, indicating a higher resistance of the electrolyte ion diffusion into the porous structure, and hence, a lower value of limiting current density. These diffusion limitations are less evident for those samples with wider pore size, as pores act as diffusion channels favoring the kinetics

Effects of gold and PCL- or PLLA-coated silica nanoparticles on brain endothelial cells and the blood–brain barrier

• Aniela Bittner,
• Angélique D. Ducray,
• Hans Rudolf Widmer,
• Michael H. Stoffel and
• Meike Mevissen

Beilstein J. Nanotechnol. 2019, 10, 941–954, doi:10.3762/bjnano.10.95

• the bands, given in arbitrary units, and subsequent standardization on actin. rBCEC4 monolayer permeability rBCEC4 cells (90,000) were seeded per gelatin-coated Millicell® culture plate insert with 3 µm pore size (Merck Millipore, Germany) on days in vitro 0 (DIV0) and left to grow until monolayer

An efficient electrode material for high performance solid-state hybrid supercapacitors based on a Cu/CuO/porous carbon nanofiber/TiO₂ hybrid composite

• Mamta Sham Lal,
• Thirugnanam Lavanya and
• Sundara Ramaprabhu

Beilstein J. Nanotechnol. 2019, 10, 781–793, doi:10.3762/bjnano.10.78

• proportional with the pore size of the active electrode materials [14]. The synthesis of carbon materials with very high surface area and appropriate pore size suitable for supercapacitor electrodes is a major challenge. It has been shown that this could be achieved by addition of sacrificial polymers, which

• room temperature. The surface area and pore size analysis were performed using a Micromeritics ASAP 2020 instrument using Brunauer–Emmett–Teller (BET) adsorption theory. Degassing under high vacuum (10−6 mbar) at 200 °C was performed for samples before the surface area and pore size analysis

• , to study the porous structures and surface area, N2 adsorption–desorption isotherms and the pore size distribution were analyzed for the Cu/CuO/PCNF/TiO2 composites. To determine the performance of the supercapacitors, the surface area and pore size distribution are two important factors to provide

On the transformation of “zincone”-like into porous ZnO thin films from sub-saturated plasma enhanced atomic layer deposition

• Alberto Perrotta,
• Julian Pilz,
• Stefan Pachmajer,
• Antonella Milella and
• Anna Maria Coclite

Beilstein J. Nanotechnol. 2019, 10, 746–759, doi:10.3762/bjnano.10.74

• ZnO [15][16]. Liang et al. [15] reported on the transformation of zincones deposited on TiO2 nanoparticles into porous ZnO via thermal treatment in the presence of air. Low surface area and wide pore size distribution (in the micropore and mesopore size range) were achieved. The surface area and the

• humidity, resulting in classical adsorption/desorption isotherms, generally categorized according to the IUPAC classification [45][46][47][48]. A type-I isotherm is associated with porous materials with a narrow distribution of pore size with a diameter below 2 nm (nanoporous or microporous materials), and

• al. [15] reported on the formation of mesoporous and microporous layers on nanoparticles coated with MLD zincone layers. In their contribution, the pore size distribution and surface area were reported as functions of the calcination temperature, showing a decrease in the overall porosity starting

Improving control of carbide-derived carbon microstructure by immobilization of a transition-metal catalyst within the shell of carbide/carbon core–shell structures

• Teguh Ariyanto,
• Jan Glaesel,
• Andreas Kern,
• Gui-Rong Zhang and
• Bastian J. M. Etzold

Beilstein J. Nanotechnol. 2019, 10, 419–427, doi:10.3762/bjnano.10.41

• mass of the non-porous carbide core [15]. According to the IUPAC classification, the isotherm can be classified as type Ia suggesting a highly (ultra-)microporous material [27]. The pore size distribution (PSD) of the material was evaluated by using the quenched solid density functional theory (QSDFT

• (type Ib) isotherm, indicating a broad range of micropores. This is in accordance with pore size distributions obtained for TiC-CDC at 1200 °C [4][30]. The addition of 5 mg of nickel per gram of carbide (CDC-Ni5) already shows a pronounced influence on the resulting isotherm, which is a combination of

• a decrease in the adsorbed volume of N2 in the low-pressure range. The pore size distributions evaluated by the QSDFT model are displayed in Figure 6b. CDC-Ni0 displays mainly pores in the micropore regime (<2 nm). On the other hand, the CDCs produced with the aid of the nickel catalyst show pores

One-step nonhydrolytic sol–gel synthesis of mesoporous TiO₂ phosphonate hybrid materials

• Yanhui Wang,
• P. Hubert Mutin and
• Johan G. Alauzun

Beilstein J. Nanotechnol. 2019, 10, 356–362, doi:10.3762/bjnano.10.35

• with the P/Ti ratio, leading to an increase of the specific surface area and a decrease of the pore size of the hybrid samples. For a P/Ti ratio of 0.2, the volume fraction of organic octyl groups exceeds 50%. The hybrid material becomes nonporous and can be described as amorphous TiO2 clusters

• of some macropores. As SEM images do not show the presence of macropores in TiP0.05 and TiP0.02 samples, these macropores likely correspond to pores between relatively small aggregates resulting from the grinding of the samples. The pore size distribution results confirmed the presence of mesopores

• 77 K with a Micrometrics TriStar 3000 apparatus; the specific surface area was determined by the BET method in the 0.05–0.25 P/P0 range. The mesopore volume and pore size distribution were obtained by the Barrett–Joyner–Halenda (BJH) method from the desorption branch. Solid-state 31P magic angle

Site-specific growth of oriented ZnO nanocrystal arrays

• Rekha Bai,
• Dinesh K. Pandya,
• Sujeet Chaudhary,
• Veer Dhaka,
• Vladislav Khayrudinov,
• Jori Lemettinen,
• Christoffer Kauppinen and
• Harri Lipsanen

Beilstein J. Nanotechnol. 2019, 10, 274–280, doi:10.3762/bjnano.10.26

• pores of size ≈600 nm; however, many-coupled branched NCs with hexagonal shape are formed when a patterned pore size of ≈200 nm is used. X-ray diffraction data is in agreement with the observed morphology. A mechanism is proposed to interpret the observed site-specific oriented/branched growth that is

• correlated to the pore size. As ordered NC arrays have the potential to generate new collective properties different from single NCs, our first demonstration of a cost effective and facile fabrication process opens up new possibilities for devices with versatile functionalities. Keywords: electrodeposition

• of a patterned pore size in controlling the growth of array vs branched ZnO NCs is shown. A mechanism based on the nucleation and growth is proposed to understand the oriented/branched twin ZnO NC morphologies. Experimental Growth of ZnO nanocrystals An electrodeposition technique was employed to

pH-mediated control over the mesostructure of ordered mesoporous materials templated by polyion complex micelles

• Emilie Molina,
• Mélody Mathonnat,
• Jason Richard,
• Patrick Lacroix-Desmazes,
• Martin In,
• Philippe Dieudonné,
• Thomas Cacciaguerra,
• Corine Gérardin and
• Nathalie Marcotte

Beilstein J. Nanotechnol. 2019, 10, 144–156, doi:10.3762/bjnano.10.14

• ; hybrid organic–inorganic interface; mesoporous materials; nanostructured materials; polyion complex micelles; polyion electrostatic complexation; Introduction Due to their unique physicochemical properties originating from their uniform pore size and periodically arranged network at the mesoscale

• with H1-like hysteresis loop (IUPAC classification [34]) showing capillary condensation at a relative pressure p/p0 ranging from 0.42 to 0.70. This indicates that the structural mesoporosity presents a cylindrical pore geometry with a high degree of pore size uniformity. This is confirmed by the narrow

• pore size distribution (PSD) calculated from the adsorption branch by the NLDFT method (Figure S3 in Supporting Information File 1). Within that pH range, the mean pore diameter (dpore) and mesopore volume (Vmeso) slightly increase with pH (Table 1). When the synthesis was performed at 1.9 wt % of DHBC

New micro/mesoporous nanocomposite material from low-cost sources for the efficient removal of aromatic and pathogenic pollutants from water

• Emmanuel I. Unuabonah,
• Robert Nöske,
• Jens Weber,
• Christina Günter and
• Andreas Taubert

Beilstein J. Nanotechnol. 2019, 10, 119–131, doi:10.3762/bjnano.10.11

• 150 °C for 20 h prior to analysis. The surface areas were calculated either by the single-point or multipoint Brunauer–Emmett–Teller (BET) method [24]. The pore size distributions were calculated using the quenched solid density functional theory (QSDFT) methodology (part of the QuadraWin 5.05

• the specific surface areas or the pore volume is observed with increasing temperature. The specific surface areas are scattered at approximately 230 m2/g (Figure 1b), and the total pore volume scatters at approximately 0.23 cm3/g (Figure 1c). Pore size distributions (PSDs) were determined from the

Controlling surface morphology and sensitivity of granular and porous silver films for surface-enhanced Raman scattering, SERS

• Sherif Okeil and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 2813–2831, doi:10.3762/bjnano.9.263

• of argon and oxygen gas (8 sccm argon, 4 sccm oxygen gas flow at a power of 200 W for 15 min). Treatment of the so obtained oxidized silver film with pure argon rf plasma (argon flow rate 16.7 sccm, power 200 W, 15 min) results in a complex network of interconnected silver particles with large pore

• size (Figure 8a). This difference in morphology is already observed in the silver film oxidized by the argon/oxygen mixture when compared to the silver film oxidized by oxygen plasma alone (Figure S16a,d, Supporting Information File 1). The difference in the obtained morphologies can eventually be

Block copolymers for designing nanostructured porous coatings

• Roberto Nisticò

Beilstein J. Nanotechnol. 2018, 9, 2332–2344, doi:10.3762/bjnano.9.218

• and physical modifications of the PS nanostructures, since the complete removal of PMMA phase produces a hydrophobic PS surface whereas an irradiation at a pressure of 103 Pa caused the partial decomposition of the PS matrix with the modification of the material pore size and structure. By focusing on

• analogous PS-b-P4VP membranes, the results obtained for PS-b-PEO membranes evidenced that the pore dimensions of the PS-b-PEO membranes are not affected by the pH change (in contrary to PS-b-P4VP). Additionally, since the membranes with PEO moieties present hydroxy end groups, the pore size can be tailored

• ), where 2-propanol was determined to be the best solvent. As reported in Figure 4, the nanoporous thin membrane (i.e., pore size ≈20 nm) adheres to the macroporous substrate without any discontinuities. As reported in Figure 4d, the desired vertical alignment of the nanoporous system is maintained, even

Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

Nanoconjugates of a calixresorcinarene derivative with methoxy poly(ethylene glycol) fragments for drug encapsulation

• Alina M. Ermakova,
• Julia E. Morozova,
• Yana V. Shalaeva,
• Victor V. Syakaev,
• Aidar T. Gubaidullin,
• Alexandra D. Voloshina,
• Vladimir V. Zobov,
• Irek R. Nizameev,
• Olga B. Bazanova,
• Igor S. Antipin and
• Alexander I. Konovalov

Beilstein J. Nanotechnol. 2018, 9, 2057–2070, doi:10.3762/bjnano.9.195

• filtrated through Millipore filter (pore size: 0.2 μm). The series of solutions was obtained through dilution. Preparation of substrate-loaded micelles of 3 Two basic methods were used to produce 3 + substrate micelles. Thin-film hydration Appropriate amounts of 3 and substrate (Dox, Orange OT, QC, RhB, see

• residual suspensions were filtered through Millipore filter (pore size: 0.2 μm) to remove free hydrophobic substrates (Dox, Orange OT, QC) or dialysed against water (molecular weight cutoff 1000 Da) for 1 h (hydrophilic RhB). The concentrations of Dox, Orange OT, QC, RhB in the obtained 3 + substrate

Synthesis of a MnO₂/Fe₃O₄/diatomite nanocomposite as an efficient heterogeneous Fenton-like catalyst for methylene blue degradation

• Zishun Li,
• Xuekun Tang,
• Kun Liu,
• Jing Huang,
• Yueyang Xu,
• Qian Peng and
• Minlin Ao

Beilstein J. Nanotechnol. 2018, 9, 1940–1950, doi:10.3762/bjnano.9.185

• surface chemical composition results obtained from the XPS analysis ensure the formation of Fe3O4 and MnO2, which further confirms the observation from the previous structural and morphological characterization. Figure 7 shows the N2 adsorption–desorption isotherms and corresponding pore-size

• /Fe3O4/diatomite. XPS spectra of as-synthesized MnO2/Fe3O4/diatomite: (a) full survey spectrum, high-resolution scans of (b) Fe 2p, (c) Mn 2p and (d) O 1s. (a) N2 adsorption–desorption isotherms and (b) the corresponding pore-size distribution curves of diatomite, Fe3O4/diatomite and MnO2/Fe3O4/diatomite

The inhibition effect of water on the purification of natural gas with nanoporous graphene membranes

• Krzysztof Nieszporek,
• Tomasz Pańczyk and
• Jolanta Nieszporek

Beilstein J. Nanotechnol. 2018, 9, 1906–1916, doi:10.3762/bjnano.9.182

• separation relies strongly on the pore size and geometry. The presence of a strongly electronegative atom in the way of separated components may cause additional, probably undesirable effects. For example, during natural gas separation, the water molecules, which are present in the mixture, can lower the

Uniform cobalt nanoparticles embedded in hexagonal mesoporous nanoplates as a magnetically separable, recyclable adsorbent

• Can Zhao,
• Yuexiao Song,
• Tianyu Xiang,
• Wenxiu Qu,
• Shuo Lou,
• Xiaohong Yin and
• Feng Xin

Beilstein J. Nanotechnol. 2018, 9, 1770–1781, doi:10.3762/bjnano.9.168

• calculated at a relative pressure range of 0.05–0.2. The pore size distribution was determined using nonlocal density functional theory (NLDFT) with the slit pore model using the adsorption branch of the nitrogen isotherm. The magnetic properties of the NPLs were investigated by a vibrating sample

• average pore size of all samples calculated from the adsorption branch using the NLDFT method is less than 25 nm, as shown in Figure 4C, which is in good agreement with the STEM observation (Figure 3D). After heat treatment at 800 °C, the BET surface area for the samples prepared at the initial dopamine

• hydrochloride concentrations of 1.0, 2.0, and 2.5 g/L is calculated to be 59, 70, and 124 m2/g, respectively (Table S2, Supporting Information File 1). When the initial concentration of dopamine hydrochloride is decreased, the average pore size increases from 9.5 nm to 18.6 nm (Figure 4C and Table S2

Controllable one-pot synthesis of uniform colloidal TiO₂ particles in a mixed solvent solution for photocatalysis

• Jong Tae Moon,
• Seung Ki Lee and
• Ji Bong Joo

Beilstein J. Nanotechnol. 2018, 9, 1715–1727, doi:10.3762/bjnano.9.163

• adsorption/desorption isotherm and corresponding Barrett–Joyner–Halenda (BJH) pore size distributions of the TiO2 samples. The TiO2 sample calcined at 400 °C (TiO2-400) displayed a typical type IV isotherm with a well-developed hysteresis loop that indicated mesoscale porosity (Figure 5a). The TiO2 sample

• ). The measured surface area for the TiO2 samples calcined at 400, 500, 650, 800 °C were 123, 62, 5 and 5 m2/g respectively. Figure 5b provides the pore size distribution of the TiO2 sample calcined at different temperatures as calculated by the BJH method using the adsorption branch of the N2 adsorption

• were no sharp peaks in the BJH pore size distribution curves. However, once the TiO2 sample was calcined at high temperatures, e.g. more than 650 °C, they did not show any obvious peaks in the range related to mesopores, which indicated an almost non-porous characteristic. It is well-known that the

Sulfur-, nitrogen- and platinum-doped titania thin films with high catalytic efficiency under visible-light illumination

• Boštjan Žener,
• Lev Matoh,
• Giorgio Carraro,
• Bojan Miljević and
• Romana Cerc Korošec

Beilstein J. Nanotechnol. 2018, 9, 1629–1640, doi:10.3762/bjnano.9.155

• observed decrease in crystallite size, which is typical for samples synthesized with H2SO4 (≈10 nm) compared to samples synthesized with HCl (≈50 nm) [19]. Figure 3 shows the pore size distribution for a sample synthesized with HCl (REF) and H2SO4 (S3). Sample REF has a well-defined uniform pore size

• distribution (≈10 nm), whereas S3 has a multimodal pore size distribution. The distributions of pores in other samples synthesized with HCl (Urea_15, Thiourea_15) and H2SO4 (S3_N0.5, S3_N0.5+1% Pt) are similar to the distributions shown in Figure 3. Band gap measurements The diffuse reflectance, R, of the

• placed into Pt crucibles and heated from 25 to 800 °C at a heating rate of 10 °C/min. XRD patterns were measured with a Siemens D5000 instrument in the 2θ range of 23–32°. The average crystallite sizes were calculated using Scherrer’s equation. The BET specific surface area and pore size distribution of

Closed polymer containers based on phenylboronic esters of resorcinarenes

• Tatiana Yu. Sergeeva,
• Rezeda K. Mukhitova,
• Irek R. Nizameev,
• Marsil K. Kadirov,
• Polina D. Klypina,
• Albina Y. Ziganshina and
• Alexander I. Konovalov

Beilstein J. Nanotechnol. 2018, 9, 1594–1601, doi:10.3762/bjnano.9.151

• -encapsulated dyes by dialysis. Dialysis of 2 mL of the suspension was carried out in 50 mL of distilled water for three days using a dialysis bag with a pore size of 2000 Da. The UV spectrum of the dialysate was determined in the range of 200–600 nm. Determination of pKdiss and pKa values 0.3 mL of SRA (1 mM

• spectrophotometer. To study the kinetics of the pH-controlled dye release, dialysis of D@p(SRA-B) (3 mL, 0.27 mg/mL) in 50 mL of universal buffer solution (pH 3) was carried out using a dialysis bag with a pore size of 2000 Da. UV spectra of the dialysate were measured every 30 min over a time span of three hours

• -controlled dye release, dialysis of the D@p(SRA-B) solution (3 mL, 0.27 mg/mL) in 50 mL of the 0.4 mM glucose solution was carried out using a dialysis bag with a pore size of 2000 Da. UV spectra of dialysate were determined every 30 min over a time of three hours. AFM images of p(SRA-B). UV–vis and

Cr(VI) remediation from aqueous environment through modified-TiO₂-mediated photocatalytic reduction

• Rashmi Acharya,
• Brundabana Naik and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 1448–1470, doi:10.3762/bjnano.9.137

• hydrogel (rGH). The 3D macrostructures of rGH enhanced the accessible surface area and possessed highly porous structures with a pore size distribution of several micrometers, which enabled the use of the composite for the fast adsorption of Cr(VI) through π–π interactions and a nonporous surface

Preparation and morphology-dependent wettability of porous alumina membranes

• Dmitry L. Shimanovich,
• Alla I. Vorobjova,
• Daria I. Tishkevich,
• Alex V. Trukhanov,
• Maxim V. Zdorovets and
• Artem L. Kozlovskiy

Beilstein J. Nanotechnol. 2018, 9, 1423–1436, doi:10.3762/bjnano.9.135

• -monodisperse cylindrical pores [23][24]. Membranes obtained by traditional methods have a three-dimensional pore structure that has a large pore size distribution, which does not allow high permeability values to be obtained [9][25][26]. Therefore, the optimization of parameters such as the diameter and length

• aluminum layer beforehand is removed, as described previously. In the inset of Figure 2D, the split surface formation scheme is shown [34]. This explains why the pore diameter in the SEM surface photo does not coincide with the pore size obtained in the SEM cross-sectional view of the same sample. In

• homogeneity and pore size, Figure 7 shows the surface profiles of the experimental samples before and after barrier layer etching. Figure 7A,B shows the variation in pore diameter, and Figure 7C shows the distance between pores (cell diameter). The pore diameter increased from 50 ± 5 nm to 80 ± 5 nm after 30

Nanoporous silicon nitride-based membranes of controlled pore size, shape and areal density: Fabrication as well as electrophoretic and molecular filtering characterization

• Axel Seidenstücker,
• Stefan Beirle,
• Fabian Enderle,
• Paul Ziemann,
• Othmar Marti and
• Alfred Plettl

Beilstein J. Nanotechnol. 2018, 9, 1390–1398, doi:10.3762/bjnano.9.131

• silicon dioxide layers during rapid thermal annealing [13]. This fabrication offers the advantage of full compatibility to semiconductor fabrication techniques. While pore distance and pore size can be controlled within acceptable limits, the generated pores are random in position and the membrane

• ]. Selectivity and molecular cut-off depend strongly on pore size and the narrowness of its distribution. Studies of the molecular filtering properties were conducted by real-time fluorescence microscopy. Thus, the diffusion of fluorescent molecules or fluorescent-labeled macromolecules could be observed time

Facile chemical routes to mesoporous silver substrates for SERS analysis

• Elina A. Tastekova,
• Alexander Y. Polyakov,
• Anastasia E. Goldt,
• Alexander V. Sidorov,
• Alexandra A. Oshmyanskaya,
• Irina V. Sukhorukova,
• Dmitry V. Shtansky,
• Wolgang Grünert and
• Anastasia V. Grigorieva

Beilstein J. Nanotechnol. 2018, 9, 880–889, doi:10.3762/bjnano.9.82

• silver prepared at a double excess of NaBH4 is of 230 ± 90 nm (Figure 1c) and the related pore size is about 100 nm. A ten-fold excess of NaBH4 led to full conversion of polycrystalline Ag2O to ≈1 μm sponge-like Ag grains (Figure 1d), which also contained numerous mesopores. As it was discussed elsewhere

• . According to the Brunauer–Emmett–Teller (BET) surface area analysis and the Barrett–Joyner–Halenda (BJH) (BET-BJH) nitrogen capillary adsorption analysis, the specific surface area of the mesoporous silver particles (mp-Ag) reached 42 ± 5 m2/g and the pore size distribution analysis demonstrated a broad

A review of carbon-based and non-carbon-based catalyst supports for the selective catalytic reduction of nitric oxide

• Shahreen Binti Izwan Anthonysamy,
• Syahidah Binti Afandi,
• Mehrnoush Khavarian and
• Abdul Rahman Bin Mohamed

Beilstein J. Nanotechnol. 2018, 9, 740–761, doi:10.3762/bjnano.9.68

• pore size distribution can be altered to suit the requirements of a specific type of reaction. The surface chemistry of a carbon-based catalyst also plays a significant role, as it influences catalytic performance especially during the synthesis stage. In terms of interactions, carbon-based materials

Synthesis and characterization of two new TiO₂-containing benzothiazole-based imine composites for organic device applications

• Anna Różycka,
• Agnieszka Iwan,
• Krzysztof Artur Bogdanowicz,
• Michal Filapek,
• Natalia Górska,
• Damian Pociecha,
• Marek Malinowski,
• Patryk Fryń,
• Agnieszka Hreniak,
• Jakub Rysz,
• Paweł Dąbczyński and
• Monika Marzec

Beilstein J. Nanotechnol. 2018, 9, 721–739, doi:10.3762/bjnano.9.67

• , indicating the complete pore filling (according to the type IV isotherm model). However, this effect was not observed in the case of TiO2 since the material isotherm is a combination of both II and IV types. The shape of the hysteresis loop is correlated with pore size distribution and pore geometry

• the width range of 2–50 nm) and macropores (above 50 nm). Figure 1b shows the pore size distribution of TiO2. Based on the BJH method the average pore width of 6.2 nm and cumulative volume of pores of 0.117 m3/g were calculated. The obtained results indicate that the mesoporous structure of TiO2

• was achieved by argon bubbling through the solution for about 10 min before measurement. All electrochemical experiments were carried out under ambient conditions. (a) Adsorption and desorption N2 isotherms of TiO2 at liquid nitrogen temperature. (b) Pore size distribution of TiO2 using Gaussian