Atomic Layer Deposition Of TiO2 Research Articles

Atomic layer deposition of titanium dioxide on multi-walled carbon nanotubes for ammonia gas sensing

Carbon nanotube (CNTs)-metal oxide semiconductor (MOS) hybrid nanostructures can provide a new pathway for room temperature chemiresistive gas sensors due to combined properties of both the materials and the creation of heterojunctions between CNTs and MOS. Multi-walled carbon nanotubes (MWCNTs) were grown on Si substrates coated with SiO2 layer by catalytic chemical vapor deposition (CCVD) and coated by TiO2 films of different nominal thicknesses, 5, 10 and 20 nm, using atomic layer deposition (ALD). ALD is a self-limiting surface process providing highly uniform and conformal coatings if reactive sites exist on the surface. The CNT surface is quite inert and therefore, a modification of MWCNTs by carboxyl plasma polymer (PP) film was applied prior to ALD of TiO2. The carboxyl PPs improved film uniformity, even though the thinnest TiO2 film still formed an island-like structure. Raman spectroscopy revealed that coating by TiO2 or carboxyl PP increased structural disorder of sp2 carbon in the MWCNTs and the thinnest TiO2 coatings induced the lowest disorder. The thinnest coatings also resulted in the highest sensor response to NH3. Nevertheless, for all thicknesses the sensors coated with carboxyl PP/TiO2 double layer showed higher response as compared to the pristine CNTs and those without the carboxyl PP film.

Photocatalytic Lithography with Atomic Layer–Deposited TiO2 Films to Tailor Biointerface Properties

AbstractIn this article, the use of thin, photocatalytically active TiO2 films deposited using atomic layer deposition (ALD) and a conventional lithography mask are explored for the fabrication of a patterned biointerface. Hereto, a pattern of self‐assembled monolayers (SAMs) with different functional groups is created using ALD TiO2 films, anatase‐rich as‐deposited, with a thickness of 20 nm and a short UV exposure time of 5 min. More specifically, azido‐containing SAMs are locally removed upon UV exposure (λ = 308 nm) and the created gaps are filled with a polyethylene glycol (PEG) SAM, hereby creating a surface with areas for the selective coupling of biomolecules via the azide groups and antifouling areas due to the presence of the PEG. To demonstrate the effectiveness of this approach, fluorescent‐labeled antibodies are immobilized on the well‐defined patterns with a resolution in the µm range.

TiO2 ALD decorated CuO/BiVO4 p-n heterojunction for improved photoelectrochemical water splitting

Bismuth vanadate (BiVO4) is a promising photoanode material owing to the narrow bandgap, appropriate band position, and excellent resistance against photocorrosion, however, the performance of photoelectrochemical (PEC) water splitting is largely limited by the poor carrier separation and transport ability. To address these issues, for the first time, we fabricate BiVO4 film/CuO nanocone p-n junctions as photoanodes by combing a facile spin-coating process and water bath reaction. This structure strengthens the light harvesting and promotes the charge separation and transport ability. The surface defects states are passivated by coating conformally ultrathin TiO2 onto CuO surface through atomic layer deposition (ALD) technique. Benefiting from the favorable morphology, energy band, and surface treatment, the BiVO4/CuO/TiO2 heterojunction generates an improved photocurrent that is much higher than pure BiVO4. The detailed mechanism investigations indicate that the synergetic optimization of charge separation and injection efficiency in the bulk and surface of photoelectrodes can significantly improve the performance of PEC cells.

Dual Protection Layer Strategy to Increase Photoelectrode–Catalyst Interfacial Stability: A Case Study on Black Silicon Photoelectrodes

AbstractPhotoelectrode degradation under harsh solution conditions continues to be a major hurdle for long‐term operation and large‐scale implementation of solar fuel conversion. In this study, a dual‐layer TiO2 protection strategy is presented to improve the interfacial durability between nanoporous black silicon and photocatalysts. Nanoporous silicon photocathodes decorated with catalysts are passivated twice, providing an intermediate TiO2 layer between the substrate and catalyst and an additional TiO2 layer on top of the catalysts. Atomic layer deposition of TiO2 ensures uniform coverage of both the nanoporous silicon substrate and the catalysts. After 24 h of electrolysis at pH = 0.3, unprotected photocathodes layered with platinum and molybdenum sulfide retain only 30% and 20% of their photocurrent, respectively. At the same pH, photocathodes layered with TiO2 experience an increase in photocurrent retention: 85% for platinum‐coated photocathodes and 91% for molybdenum sulfide–coated photocathodes. Under alkaline conditions, unprotected photocathodes experience a 95% loss in photocurrent within the first 4 h of electrolysis. In contrast, TiO2‐protected photocathodes maintain 70% of their photocurrent during 12 h of electrolysis. This approach is quite general and may be employed as a protection strategy for a variety of photoabsorber–catalyst interfaces under both acidic and basic electrolyte conditions.

Atomic Layer Deposited TiO₂ and Al₂O₃ Thin Films as Coatings for Aluminum Food Packaging Application.

Titanium dioxide (TiO2) and aluminum oxide (Al2O3) coatings have been investigated in a wide range of bio-applications due to their biodegradation and biocompatibility properties, that are key parameters for their use in the food packaging and biomedical devices fields. The present study evaluates and compares the electrochemical behavior of the non-coated, commercial resin-coated, TiO2-coated and Al2O3-coated aluminum in commercial beer electrolyte. For this, TiO2 and Al2O3 thin films were deposited on aluminum (Al) substrates using atomic layer deposition (ALD). The evaluation of the corrosion barrier layer properties was performed by linear sweep voltammetry (LSV) during 10 min and electrochemical impedance spectroscopy (EIS). In addition, profilometry, grazing incidence X-ray diffractometry (GIXRD), scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) analyses were performed to investigate the physical and chemical properties of the pristine and / or corroded samples. TiO2 and Al2O3 films presented an amorphous structure, a morphology that follows Al substrate surface, and a thickness of around 100 nm. Analysis of LSV data showed that ALD coatings promoted a considerable increase in corrosion barrier efficiency being 86.3% for TiO2-coated Al and 80% for Al2O3-coated Al in comparison with 7.1% of commercial resin-coated Al. This is mainly due to the lower electrochemical porosity, 11.4% for TiO2-coated Al and 20.4% for Al2O3-coated Al in comparison with 96% of the resin-coated Al, i.e. an increase of up to twofold in the protection of Al when coated with TiO2 compared to Al2O3. The EIS results allow us to complement the discussions about the reduced corrosion barrier efficiency of the Al2O3 film for beer electrolyte once SEM and FT-IR analyzes did not show drastic changes in both investigated ALD films after the corrosion assays. The above results indicate that ALD TiO2 and Al2O3 films may be a viable alternative to replace the synthetic resin coatings frequently used in aluminum cans of use in the food industry.

TiO2 ALD Coating of Amorphous TiO2 Nanotube Layers: Inhibition of the Structural and Morphological Changes Due to Water Annealing.

The present work presents a strategy to stabilize amorphous anodic self-organized TiO2 nanotube layers against morphological changes and crystallization upon extensive water soaking. The growth of needle-like nanoparticles was observed on the outer and inner walls of amorphous nanotube layers after extensive water soakings, in line with the literature on water annealing. In contrary, when TiO2 nanotube layers uniformly coated by thin TiO2 using atomic layer deposition (ALD) were soaked in water, the growth rates of needle-like nanoparticles were substantially reduced. We investigated the soaking effects of ALD TiO2 coatings with different thicknesses and deposition temperatures. Sufficiently thick TiO2 coatings (≈8.4 nm) deposited at different ALD process temperatures efficiently hamper the reactions between water and F− ions, maintain the amorphous state, and preserve the original tubular morphology. This work demonstrates the possibility of having robust amorphous 1D TiO2 nanotube layers that are very stable in water. This is very practical for diverse biomedical applications that are accompanied by extensive contact with an aqueous environment.

Light-driven water oxidation by a dye-sensitized photoanode with a chromophore/catalyst assembly on a mesoporous double-shell electrode.

A mesoporous atomic layer deposition (ALD) double-shell electrode, Al2O3 (insulating core)//ALD ZnO|ALD TiO2, on a fluorine-doped tin oxide (FTO) conducting substrate was explored for a photoanode assembly, FTO//Al2O3 (insulating core)//ALD ZnO|ALD TiO2|-chromophore-catalyst, for light-driven water oxidation. Photocurrent densities at photoanodes based on mesoporous ALD double-shell (ALD ZnO|ALD TiO2|) and ALD single-shell (ALD ZnO|, ALD TiO2|) electrodes were investigated for O2 evaluation by a generator-collector dual working electrode configuration. The high photocurrent densities obtained based on the mesoporous ALD ZnO|ALD TiO2 photoanode for O2 evolution arise from a significant barrier to back electron transfer (BET) by the optimized tunneling barrier in the structure with the built-in electric field at the ALD ZnO|ALD TiO2 interface. The charge recombination is thus largely decreased. In the films, BET following injection has been investigated through kinetic nanosecond transient absorption spectra, and the results of energy band analysis are used to derive insight into the internal electronic structure of the electrodes.

Enhancing the activity of oxygen-evolution and chlorine-evolution electrocatalysts by atomic layer deposition of TiO2.

We report that TiO2 coatings formed via atomic layer deposition (ALD) may tune the activity of IrO2, RuO2, and FTO for the oxygen-evolution and chlorine-evolution reactions (OER and CER). Electrocatalysts exposed to ~3–30 ALD cycles of TiO2 exhibited overpotentials at 10 mA cm–2 of geometric current density that were several hundred millivolts lower than uncoated catalysts, with correspondingly higher specific activities. For example, the deposition of TiO2 onto IrO2 yielded a 9-fold increase in the OER-specific activity in 1.0 M H2SO4 (0.1 to 0.9 mA cmECSA–2 at 350 mV overpotential). The oxidation state of titanium and the potential of zero charge were also a function of the number of ALD cycles, indicating a correlation between oxidation state, potential of zero charge, and activity of the tuned electrocatalysts.

Atomic-layer-deposited TiO2 with vapor-grown MAPbI3−xClx for planar perovskite solar cells

TiO2 thin films as electron-transporting layers for planar-type perovskite solar cells were prepared by atomic layer deposition (ALD). Perovskite MAPbI3−xClx thin films were formed on the ALD TiO2 by sequential vapor processing. The resulting perovskite thin films were uniform and pinhole-free, with an average grain size of ∼370 nm. The high crystallinity of the perovskite layers was also confirmed, with an optical bandgap of ∼1.58 eV. Planar n-i-p solar cells were formed using the ALD TiO2 and vapor-grown perovskite. The deposition temperature and thickness of the ALD TiO2 were optimized, resulting in a superior efficiency of ∼11.6% compared to conventional TiO2.

Development of ALD Coatings for Harsh Environment Applications.

Atomic layer deposition (ALD) is a well-known technique for the fabrication of ultrathin and highly conformal barrier coatings which have extensively been used for the protection of electronic devices in open atmospheric conditions. Here, we extend the scope for the application of low-temperature-deposited plasma-enhanced ALD barrier coatings for the protection of devices in a variety of chemical environments. The chemical stability tests were conducted in 3.5% NaCl, sea water, HCl (pH 4), and H2SO4 (pH 4) solutions for ALD Al2O3, HfO2, TiO2, and ZrO2, deposited at 100 °C on TiO2-coated Au and ALD ZnO (photoactive)-coated Si substrates. Using electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) study, various aspects of the barrier properties and performance of ALD films in harsh chemical environments were explored. We demonstrate that the combined approach involving EIS and PL provides unique insights into the suitability of ALD films as barriers in harsh environments involving ionic solutions. The observations from EIS and PL tests are supported by the X-ray photoelectron spectroscopy analysis of ALD materials. Of the materials tested, ALD TiO2 and ZrO2 were found to be the most stable, chemically, in all four solutions, whereas TiO2 was a better permeation barrier.

Analysis of TiO2 Atomic Layer Deposition Surface Chemistry and Evidence of Propene Oligomerization Using Surface-Enhanced Raman Spectroscopy.

Atomic layer deposition (ALD) of TiO2 was performed in tandem with in situ surface-enhanced Raman spectroscopy (SERS) to monitor changes in the transient surface species across multiple ALD cycles. A self-assembled monolayer of 3-mercaptopropionic acid was used as a capture agent to ensure that nucleation of the titanium precursor (titanium tetraisopropoxide [TTIP]) occurs. Comparisons between the Raman spectra of the neat precursor and the SER spectra of the first ALD cycle of TiO2 reveal typical ligand exchange chemistry taking place, with self-limiting behavior and intact isopropoxide ligands. However, subsequent cycles show drastically different chemistry, with no isopropoxide ligands remaining at any point during the second and third cycles. Continuous exposure of either TTIP or isopropyl alcohol after the first cycle shows unlimited chemical vapor deposition (CVD)-type growth. Comparisons with alternative precursors (aluminum isopropoxide, titanium tert-butoxide, and titanium propoxide) and DFT calculations reveal that, for the TTIP precursor, isolated TiO2 sites play a role in the dehydration of off-gassing isopropyl alcohol. The resulting propene then undergoes oligomerization into six-carbon olefins before polymerizing into indistinguishable carbon products that accumulate on the surface. The emergence of the dehydration chemistry is expected to be exclusively the result of these isolated TiO2 sites and, as such, is expected to occur on other surfaces where TiO2 ALD is feasible. This work showcases how seemingly innocuous ALD can evolve into a CVD process when the products can participate in various side reactions with newly made surface sites.

Controlled TiO2 Growth on Reverse Osmosis and Nanofiltration Membranes by Atomic Layer Deposition: Mechanisms and Potential Applications.

Enhancing the chemical and physical properties of the polyamide active layer of thin-film composite (TFC) membranes by surface coating is a goal long-pursued. Atomic layer deposition (ALD) has been proposed as an innovative approach to deposit chemically robust metal oxides onto membrane surfaces due to its unique capability to control coating conformality and thickness with atomic scale precision. This study examined the potential to coat the surface of TFC reverse osmosis (RO) and nanofiltration (NF) membranes via ALD of TiO2. Our results suggest that the optimal ALD conditions, the film growth kinetics, and the depth of deposition are different for RO and NF membranes due to the different diffusive transport of ALD precursors through the membrane pores. The TiO2 coating mainly located at the surface of the RO membrane; in contrast, the TiO2 coating extended to the depth of the NF membrane. The TiO2 coating degraded membrane water permeability and salt rejection beyond 10 cycles of ALD, the condition commonly employed in previous ALD-based membrane modification studies. Instead, this study showed that with fewer than 10 cycles, the TiO2 coating of RO membrane increased the membrane surface charge without negatively impacting water permeability and salt rejection. For the NF membranes, the coating of TiO2 inside their pores led to the tuning of pore sizes and increased the rejection of selected solutes.

Electrochemical and Structural Investigation on Ultrathin ALD ZnO and TiO2 Coated Lithium-Rich Layered Oxide Cathodes

Ultrathin coatings (1.5 ± 0.3 nm) of titanium dioxide and zinc oxide were deposited on lithium-rich layered oxide cathodes (Li1.2Mn0.6Ni0.2O2, LLO) by atomic layer deposition (ALD). The structures, electrochemical performances, and thermal stabilities of these coatings were investigated. An ultrathin uniform coating was obtained for TiO2 but not for ZnO because of differences in the layer growth mechanism. Regarding the initial charge–discharge curves under a current density of 0.04 C rate, the TiO2 coated samples exhibited a higher discharge capacity, 242 mAhg–1, compared with the ZnO coated samples, 220 mAhg–1, or the pristine samples, 228 mAhg–1. Both coated samples exhibited more stable cycling performance and thermal stability than the pristine samples. After 80 cycles under 0.5 C rate, the TiO2 and ZnO coated samples were found to have higher capacity retention (∼94% and 78%, respectively) than the pristine samples (68%). The reaction temperature of the exothermic peak of the TiO2 and ZnO coated sam...

Fabrication of buried nanostructures by atomic layer deposition

We present a method for fabricating buried nanostructures by growing a dielectric cover layer on a corrugated surface profile by atomic layer deposition of TiO2. Selecting appropriate process parameters, the conformal growth of TiO2 results in a smooth, nearly flat-top surface of the structure. Such a hard surface can be easily cleaned without damage, making the nanostructure reusable after contamination. The technique has wide applicability in resonance-domain diffractive optics and in realization of quasi-planar metamaterials. We discuss design issues of such optical elements and demonstrate the method by fabricating narrow-band spectral filters based on the guided-mode resonance effect. These elements have strong potential for, e.g., sensing applications in harsh conditions.

Atomic layer deposition of Al2O3 and TiO2 on MoS2 surfaces

In this work, the authors compare the surface coverage obtained in the initial and intermediate steps of Al2O3 and TiO2 atomic layer deposition on MoS2 surfaces prepared by either mechanical exfoliation or chemical vapor deposition (CVD). They find that the film surface coverage is highly dependent on the origin and preparation of the MoS2 starting surface. While mechanical exfoliation can be used to quickly obtain few-layer MoS2 surfaces, these surfaces exhibit significant variability in quality and cleanliness, leading to unpredictable film growth. Conversely, MoS2 grown by CVD provides a more reliable starting surface resulting in significantly improved scattering in the surface coverage. They find that, on CVD MoS2, neither Al2O3 nor TiO2 film growth strongly exhibits temperature dependence described by the Langmuir adsorption model. For both processes, films up to 6 nm thick deposited on CVD MoS2 are not fully coalesced and exhibit a large concentration of pinhole type features.

Forced flow atomic layer deposition of TiO2 on vertically aligned Si wafer and polysulfone fiber: Design and efficacy of conduit plates and soak function.

The effectiveness of three different designs of conduit plates was verified for even distribution of precursors in a voluminous forced-flow atomic layer deposition (ALD) chamber designed to hold macroscopic elongated substrates vertically. Furthermore, a new "soak function" was introduced in the controlling software of the ALD instrument. This function enabled increase in residence time of the precursor in the chamber without escalating the dosage. The flow of precursors guided by the conduit plates with and without application of the soak function was simulated using computational fluid dynamics. A conformal coating of TiO2 with good uniformity on Si and porous polysulfone fibers was achieved to evidence the design and efficacy of conduit plates and soak function.

In situ construction of interconnected SnO2/nitrogen-doped Carbon@TiO2 networks for lithium-ion half/full cells

A one-pot in situ pyrrole polymerization strategy, followed by controllable atomic layer deposition of TiO2 and pyrolysis process, is carried out to construct the core-shell SnO2/NC@TiO2 with sub-5 nm SnO2 nanoparticles uniformly dispersing in interconnected nitrogen-doped carbon nanospheres coated by TiO2 layer. Benefiting from the unique structural stability of SnO2/NC@TiO2, as anode materials for LIBs, they show much improved cycling stability and rate capability compared with the bare SnO2 and SnO2/NC electrodes. Specifically, the SnO2/NC@TiO2 electrode with a 10 nm TiO2 coating layer demonstrate the optimal lithium ion storage performance, delivering initial discharge capacity of 1224 mAh g−1 with a first-cycle Columbic efficiency of 72.3% and 871 mAh g−1 after 200 cycles at 100 mA g−1. Moreover, the assembled SnO2/NC@TiO2//LiFePO4 full cell demonstrates a good rate capability with a reversible capacity of 145 mAh g−1 (67% capacity retention of the initial value) when the electrode undergoes various current densities after 70 cycles. The improved electrochemical performance is mainly attributed to the surface interface engineering by the interconnected carbon matrix as well as the uniform TiO2 outer layer. These achieved results suggest that interconnected SnO2/NC@TiO2 electrodes have the potential to be used as anode for high-performance lithium ion battery.

Oriented Attachment and Nanorod Formation in Atomic Layer Deposition of TiO2 on Graphene Nanoplatelets.

Understanding the spontaneous organization of atoms on well-defined surfaces promises to enable control over the shape and size of supported nanostructures. Atomic layer deposition (ALD) boasts atomic-scale control in the synthesis of thin films and nanoparticles. Yet, the possibility to control the shape of ALD-grown nanostructures remains mostly unexplored. Here, we report on the bottom-up formation of both linear and V-shaped anatase TiO2 nanorods (NRs) on graphene nanoplatelets during TiCl4/H2O ALD carried out at 300 °C. NRs as large as 200 nm form after only five ALD cycles, indicating that diffusional processes rather than layer-by-layer growth are behind the NR formation. In particular, high-resolution transmission electron microscopy reveals that the TiO2 NRs and graphene nanoplatelets are in rotational alignment as a result of lattice matching. Crucially, we also show that individual nanocrystals can undergo in-plane oriented attachment.

Ultrathin Surface Coating Enables Stabilized Zinc Metal Anode

AbstractWith the rapid development of energy storage devices, aqueous battery with noncombustion properties and instinct safe features has received great attentions and Zn anode is investigated intensively due to its high theoretical capacity (820 mAh g−1), and low negative potential (−0.762 V vs SHE). However, the unavoidable gas evolution hinders the cyclability and the application in the commercial field. Herein, the atomic layer deposition of TiO2 coating is first demonstrated as the protection layer of metallic zinc anode. The corrosion of zinc plate is significantly suppressed, leading to less gas evolution and Zn(OH)2 byproduct formation. The reduced gas generation on the outer surface of the zinc plate will maintain the effective contact area between the electrolyte and anode and leads to an improved coulombic efficiency. In this way, the Zn anode with 100 ALD cycles TiO2 protection shows reduced overpotential (72.5 mV) at 1 mA cm−2 for Zn–Zn symmetrical battery and additionally, the protection of TiO2 extended the Zn–MnO2 battery cycling performance up to 1000 cycles with the capacity retention of 85% at current density of 3 mA cm−2. The novel design of atomic layer deposition protected metal zinc anode brings in new opportunities to the realization of the ultrasafe aqueous zinc metal batteries.

(Invited) The Benefits of Nanoscale Metal Oxide Films to Solar Fuels Research

Though the field of photoelectrochemical (PEC) solar fuel production focuses on a broad variety of materials, metal oxides are probably the most commonly employed materials in state-of-the-art photoelectrodes. Metal oxides such as bismuth vanadate and hematite are currently intensely studied as photoanode materials in our group and by the PEC water oxidation community.1-4 Stable metal oxides such as TiO2 have been successfully employed as protection layers in, for example, Cu2O photocathodes and are now advancing the field of organic photocathodes for hydrogen evolution.5, 6 Especially metal oxides grown by atomic layer deposition (ALD) offer many benefits to solar fuel research such as i) precise growth control on the atomic scale ii) conformal and pinhole-free coatings and ii) formation of high-quality interfaces. In our studies of recombination losses, we benefit from high-quality ALD hematite films and are able to gain new insights from electrochemical impedance spectroscopy that will be reported here. Furthermore, we could demonstrate stable organic photocathodes for hydrogen evolution and will report on new organic photocathode designs employing ALD TiO2 electron selective layers.6 Finally, I will discuss the importance of ALD surface treatments in the science of CO2 reduction.7 Le Formal, F.; Pastor, E.; Tilley, S. D.; Mesa, C. A.; Pendlebury, S. R.; Gratzel, M.; Durrant, J. R. Rate Law Analysis of Water Oxidation on a Hematite Surface. Journal of the American Chemical Society 2015, 137, 6629-6637.Mesa, C. A.; Kafizas, A.; Francas, L.; Pendlebury, S. R.; Pastor, E.; Ma, Y. M.; Le Formal, F.; Mayer, M. T.; Gratzel, M.; Durrant, J. R. Kinetics of Photoelectrochemical Oxidation of Methanol on Hematite Photoanodes. Journal of the American Chemical Society 2017, 139, 11537-11543.Ma, Y. M.; Mesa, C. A.; Pastor, E.; Kafizas, A.; Francas, L.; Le Formal, F.; Pendlebury, S. R.; Durrant, J. R. Rate Law Analysis of Water Oxidation and Hole Scavenging on a Bivo4 Photoanode. Acs Energy Letters 2016, 1, 618-623.Ma, Y. M.; Kafizas, A.; Pendlebury, S. R.; Le Formal, F.; Durrant, J. R. Photoinduced Absorption Spectroscopy of Copi on Bivo4: The Function of Copi During Water Oxidation. Advanced Functional Materials 2016, 26, 4951-4960.Luo, J. S.; Steier, L.; Son, M. K.; Schreier, M.; Mayer, M. T.; Gratzel, M. Cu2o Nanowire Photocathodes for Efficient and Durable Solar Water Splitting. Nano Letters 2016, 16, 1848-1857.Steier, L.; Bellani, S.; Rojas, H. C.; Pan, L. F.; Laitinen, M.; Sajavaara, T.; Di Fonzo, F.; Gratzel, M.; Antognazza, M. R.; Mayer, M. T. Stabilizing Organic Photocathodes by Low-Temperature Atomic Layer Deposition of Tio2. Sustainable Energy & Fuels 2017, 1, 1915-1920.Schreier, M.; Heroguel, F.; Steier, L.; Ahmad, S.; Luterbacher, J. S.; Mayer, M. T.; Luo, J. S.; Gratzel, M. Solar Conversion of Co2 to Co Using Earth-Abundant Electrocatalysts Prepared by Atomic Layer Modification of Cuo. Nature Energy 2017, 2.