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Novel Self-cleaning, anti-bacterial coatings, preventing disease transmission on everyday touched surfaces

Final Report Summary - SELFCLEAN (Novel Self-cleaning, anti-bacterial coatings, preventing disease transmission on everyday touched surfaces)

Executive Summary:
SELFCLEAN is a successful 2 years project within the EU Seventh Research Frame Programme (FP7) in the area of Research for the benefit of SMEs. 9 partners from 5 different countries engaged in the development of new self-cleaning-antibacterial coatings of high aesthetics and durability by electroplating technology, targeting to meet the important need of public hygiene in common touched surfaces as knobs and handles.
The main scope of SelfClean project was to overturn the current downward trend in European electroplating and nanotechnology industry by offering in the market innovative “self cleaning – antibacterial coatings” that will meet the important social need of public hygiene and will allow sales growth rate for the participating SMEs.
Hygiene/antimicrobial issues in public places (hospitals, schools, restaurants, public transportation etc) are of crucial importance as inattention could lead to spread of viral diseases or epidemics and consequently to deaths. A typical example is that of hospital acquired infections (HAI). According to The European Centre for Disease Prevention and Control (ECDC) in the EU, about 3,000,000 are infected annually with HAI and about 25,000 patients die from this. The SMEs of the consortium having identified this Need and a NEW Market for their products propose the solution of self-cleaning, antibacterial electrolytic (metallic) coatings of Sn-Ni matrix with doped TiO2 nanoparticles as a reinforcing mean.
The SelfClean project in just 24 months produced successfully Novel self cleaning – antibacterial coatings of high aesthetics and durability based on the photocatalytic properties of “SelfClean doped” TiO2 nano-particles, immobilized in Sn-Ni matrix that are able to operate in indoor light in addition to UV-light. The immobilization (incorporation) of these doped-TiO2 nanoparticles in the Sn-Ni matrix -typically exhibiting high esthetics coatings- give to the alloy coatings Unique self-cleaning and antibacterial properties.These coatings have been applied to common touched objects and handles in Metropolitan Hospital, via the process of electroplating and reduced the risk of getting infected by communicable diseases by a factor of 60% (in some cases above 80%).
The SelfClean composite coatings present the following truly advanced elements for the SME partners:
• World’s first metal matrix composite coating reinforced by TiO2 nanoparticles operating as a self cleaning – antibacterial coating under indoor light irradiation applied in common touched objects.
• Doped TiO2 nanoparticles with band gap less than 2.3 eV, able to be activated by indoor light irradiation, via a process easily up scalable by NADICO.
• Optimized Pulse current electroplating process enabling high codeposition rate of doped TiO2 nanoparticles and rather uniform distribution in the tin-nickel matrix, easily adaptable by ELPLATEK succeeding to reduce consumption of raw materials, energy and time.

SelfClean Project Gave the participating EU SMEs long term competitive advantage in novel “self cleaning – antibacterial coatings” manufacture enabling a technological leap towards indoor usage.
Project Context and Objectives:
SelfClean aimed to overturn the current downward trend in European electroplating industry by offering in the market innovative “self cleaning – antibacterial coatings” that will meet the important social need of public hygiene and will allow sales growth rate for the participating SMEs.
In order to successively produce the metal articles with combine the self-cleaning and the antibacterial actions, knowledge from different scientific and technological fields was combined during the last 24 months: chemical companies, metal articles manufacturers, plating industry and a Hospital were the optimized project’s products were applied and tested.
Technical challenges of the project:
o The chemical modification (doping) of TiO2 nanoparticles in order to achieve lower band gap and thus become capable of operating in indoor light. This type of product would be of an added value for NADICO.
o Development of sol-gel mass production method of doped-TiO2 nanoparticles.
o Development of pulse plating process in order to achieve high incorporation rate and uniform distribution of reinforcing nanoparticles on the surface of metal/alloy matrix leading to an effective immobilization of photocalalytic particles. Optimization of the pulse plating process in order to be sustainable in terms of saving energy, time and raw materials.
o Realization of robust process parameters.
o Enhancement of functional propertied of produced coating exhibiting high adhesion with the substrate.
o Testing the self – cleaning and antibacterial character of the coating under different relevant light conditions (Proof of concept).

The SelfClean project within 24 months achieved all specific objectives for the individual research work packages 1 to 7. The outcome of these individual research work packages culminated in the development, demonstration and dissemination of produced novel self cleaning – antibacterial coatings of high aesthetics and durability based on the photocatalytic and antimicrobial properties of the doped TiO2 nano-particles immobilized in Sn-Ni matrix, when exposed to indoor light. These coatings were applied to common touched objects via the process of electroplating. It should be mentioned that in some cases (e.g. plates plated with Sn-Ni/TiO2 by the up-scale bath), showed in the 82% of the measurement better results comparing to the common surfaces of the hospital. Thus, the consortium considers to have achieved proving the overall concept of the SelfClean project.

The Technical & Scientific Objectives of the SelfClean project in combination with the means of verification as well as the related deliverables and milestones
Technical Objectives:
• Delivery of doped-TiO2 nanoparticles exhibiting photocatalytic activity in visible light irradiation. Means of verification: by a) measuring energy bang gap and b) testing the powder’s photocatylitic action under visible light irradiation.
• Delivery of production line of doped TiO2 nanoparticles. By producing 5 batches of 100 g of doped-TiO2.
• Delivery of a direct - pulse electroplating process for tin-nickel matrix self cleaning – antibacterial coatings, exhibiting enhanced mechanical & anticorrosion properties, with current efficiency > 95%. By coating 10 samples in the electroplating line and testing the deposits in a series of analyses. Current efficiencies were calculated via the monitoring of electrical signals.
• Achievement of TiO2 codeposition rate up to 20 wt. % (~30 vol. %) in the composite coating. Determination of TiO2 codeposition rate of coatings by applying XRF and EDS techniques.
• Plating of metal articles surface with the self cleaning – antibacterial coating.
Scientific Objectives:
• To reduce energy band gap value of TiO2 nanoparticles by doping to less than 2.3eV. Means of verification: By measuring energy band gap.
• Advances in 2 years in producing doped-TiO2 nanoparticles operating as photocatalyst in indoor applications. Means of verification: By: a) the filling of a possible patent application for the benefit of SME partners and b) by successful build of a prototype production line of doped-TiO2 nanoparticles.
• Advances in 2 years in pulse current plating technique for coating Sn-Ni/doped-TiO2 composite coatings with high codeposition percentage (>20 wt.%). Means of verification: By: a) the filling of a possible patent applications of the benefit of SME partners and b) prove by surface quantitative analysis (XRD, EDS) of the TiO2 percentage.
• To produce Sn-Ni/doped-TiO2 coatings with identical mechanical and anti-corrosion properties to the existing products and high adhesion, and that will be achieved by measuring hardness, wear and corrosion resistance as well as adhesion.
Project Results:
During the 24 months of the project significant S&T have been achieved
o A specification report considering the requirements of the end users has been delivered (WP1)
o Suitable element for doping TiO2 nanoparticles have been selected (WP2)
o Samples of 50 g of TiO2 doped nanoparticles with a band gap of < 2.3 eV have been delivered (WP2)
o 2 best doped-TiO2 compositions that resulted from the study on WP2 have been progressed for upscaling and were synthesized in quantities of 1 kg of each of the systems in multiple batches via a sol-gel method. (WP3)
o A method for the mass production of doped-TiO2 nanoparticles has been developed (WP3)
o The doped-TiO2 nanoparticles have been extensively characterized by using physical and chemical methods (WPs 2 & 3).
o The integrated prototype production line for direct and pulse current electrodeposition has been delivered (WP4)
o 2 x 10 Metal articles (4x4 com sheets) were usefully coated with Sn-Ni matrix composite coatings reinforced by doped-TiO2 nanoparticles under the optimal found conditions, both by the implosion of DC (WP4) and PC (WP5) conditions.
o 2 detailed reports with all results of the structural, morphological, mechanical and photocatalytic and antimicrobial characterization of the produced coatings were delivered making feasible the selection of optimum electroplating conditions both under DC (WP4) and PC (WP5) plating.
o Reliability tests for plated metal articles with SELFCLEAN coatings (both in Lab and Real environment) have been performed.
o The proof of indoor photocatalytic activity and self-cleaning character of the SnNi/doped-TiO2 electrocoatings applied on door knobs, handles and metallic surfaces provided by Metropolitan hospital and tested “on site” has been verified. (WP6)
o The SelfClean website has been created (WP 7)
o Produce a plan for the use, dissemination and exploitation of the knowledge (WP7)
o Detailed Report on Patent search, identifying the possibility for a new patent for ELPLATEK (WP7)

Work Package 1: Generation of specifications and requirements data
The general objective of WP1 was to generate specifications and requirements of the materials, chemistries and equipment to be used within the project, targeting to the semi industrial scale production of the novel SelfClean coatings applied on metal articles such as handles, knobs, taps or bed parts, by the end of the SelfClean Project (February 2015) while the following characteristics will be present:
a. will be durable (wear and corrosion resistant)
b. of high aesthetics,
c. and will exhibit unique self cleaning and antibacterial properties under indoor light irradiation, verified in real hospital environment.
Work Package 2: Selection of suitable doping elements for TiO2 nanoparticles
The objective of WP2 was to determine the suitable elements to dope the TiO2 via sol-gel method, targeting in delivering 50g of doped TiO2 powders with a band gap < 2.3 eV.
Reports D2.1 and D2.2 contain results of analysis and characterization of the successfully produced doped-TiO2 nano-powders. A number of doped- TiO2 powders were synthesized and among them eight different groups of doped powders (N- doped, S and N-doped, N and Ag-doped, N,S and Ag-doped, Fe-doped) were finally progresses for further investigation, since only those met the requirements regarding conditions set for powder production in WP1.
Finally, five different synthesized powders characterized as most promising have been fully characterized with respect to powder size, morphology, composition, Zeta-potential, band-gap, photocatalytic properties, and antimicrobial properties. In D2.1 it is documented that the RTD partners involved in WP2 managed to reduce the band gap of the SelfClean doped TiO2 nanopowders to values lower than 2.2eV with a size of particles below 100nm. Though, NADICO in close collaboration with NTUA and IPU progressed only 2 out of the 5 extensively characterized powders for an up-scaled production within WP3, since those exhibited profound antimicrobial activity among the 5 tested. The powders selected were the N-S doped TiO2 (DNT1th) and the N-Ag co-doped (DNT1Ag2), respectively. DNT1th found to have a band gap below 2.3eV whereas the band gap of the second powder could not be determined with the applied method due to its high silver content. It is worth mentioning that, the important Go/no-Go milestone for the project at month 9 has been successfully met.
The sol-gel production process was designed in such a way to be efficient and scalable to the material amounts given in the DoW. Solvents used in the sol-gel production process should preferentially be water and alcoholic solvents. Finally, a water based sol-gel synthesis was applied. The precursor materials used for the synthesis were chosen so as to be of low price and as simple as possible and not hazardous. The sol-gel process could be easily adapted to different kinds of dopants, moreover, the number of heat treatment steps during the production process have been optimized to the minimum number.

Work Package 3: Production of doped TiO2 nanoparticles via sol-gel method
The objective of WP3 was to develop a suitable method from techno-economical point of view, for the mass production of doped-TiO2 nanoparticles, plus to characterize the selected two doped-TiO2 nano-particulates via numerous physical and chemical methods, likewise in WP2.
Deliverables D3.1 and D3.2 enclose detailed description on the development of the up-scaling procedures for the 2 doped TiO2 powders, enabling the production of batches of 100g doped powders plus all the applied productions steps, which with sufficient investments, can be further scaled to the desired volume of the future production.
It is worth to be mentioned that, only few synthesis steps developed in WP2 were modified in order to enable up-scaling. The up-scaled powders have been characterized with respect to content of dopants, crystallography, morphology and particle size, band gab, photocatalytic activity and antimicrobial effect. The dopants were identified in the produced powders, while the particulates size was found to be smaller as compared to the powders synthesized inWP2. The up-scaled powders showed a predominantly anatase phase, and the lowest band gab was determined to be equal to 2.27eV. Photocatalytic activity according to ISO 10678-10 of the up-scaled powders has been confirmed as well as an antimicrobial effect by the so-called Shake Flask Test.
Finally, as both of the up-scaled produced powders showed sufficient photocatalytic activity, it was recommended to base the decision on which of the powders to prioritize in the future activities, on the criteria related to simplicity of production and economics.

WP4: Direct current electrodeposition of Sn- Ni/doped-TiO2 composite coatings
The specific objectives of WP4 were namely:(a) to set up the electroplating equipment, and agitation system for direct (DC) and pulse current (PC) electrodeposition, (b) to adjust plating solution in avoidance of particles agglomeration and towards high incorporation percentages, (c) to determine the optimum electroplating conditions for DC plating via multidisciplinary characterization techniques and finally deliver metal articles coated by the SelfClean composite coating under the optimal conditions.
All aforementioned objectives were successfully met on time. Specifically, two laboratory apparatus were designed and constructed towards the optimization of the electrolytic parameters for the production of high aesthetic Ni-Sn/TiO2 coatings exhibiting high incorporation percentages (D4.1). Following the optimization, two up-scaled apparatus were designed and fabricated in order to be able to coat real objects in semi-industrial scale. The bath dimensioning, the type of agitation, imposition of hydrodynamic conditions and working temperature, the proper filtering of the bath, etc. resulted to have great influence on the composite coating’s appearance and properties (both mechanical and photo-induced). Optimal electroplating parameters were determined and thus Ni-Sn/TiO2 coatings on 4x4 cm metal articles were successfully produced on time (before month X). The optimized samples are summarized in deliverable D4.2 whilst, in D4.3 a detailed description of the production parameters optimization and the novel coatings properties characterization is reported.
Within the frame of WP4 the proof of indoor photocatalytic activity and self-cleaning character of the novel SnNi/SelfClean doped-TiO2 electrodeposits, produced under direct current conditions, has been verified according to ISO 10678-10 (after proper adjustment of the protocol to the geometry of the investigated samples, sheets 1x1 cm) and D7490. It is worth mentioning that, there is no previous indication concerning the utilization of the Sn/Ni electrolyte in combination with the TiO2 as reinforcing particles, thus a characterization of the effect of the addition of particles into the Elplatek proprietary bath was also carried out by meaning of pH and F- measurement. Reference commercial powders, both doped and non-doped, were also taken into consideration as reference.

WP5: Development of PC plating technique for Sn-Ni/doped-TiO2 composite coatings
Based on the optimum electroplating conditions for DC plating that were defined in the WP4, Pulse Plating technique was applied aiming to the increase of particles codeposition in the surface of metal matrix within WP5. According to the DOW along with the imposition of PC regime the addition of additives in the electroplating bath should be tested, aiming to the production of composite coatings with high percentage of doped-TiO2 nanoparticles and appearance of high aesthetics. However, the results from WP4 for coatings under DC in the presence of additives revealed no beneficial effect on codeposition percentage of titania particles and therefore it was decided from the partners not to be examined in this WP5. Four different types of Sn-Ni/TiO2 composite coatings were produced under optimum DC conditions associated with the four different types of TiO2 powders investigated within WP4. All composite coatings are mat grey due to the incorporation of the TiO2 nanoparticles within the alloy, stable, homogeneous, adherent and compact. The proof of indoor photocatalytic activity and self-cleaning character of the SnNi/SelfClean doped-TiO2 electrodeposits produced under direct current conditions has been verified.

WP6: Proof of self cleaning – antibacterial action of coatings on metal articles
The aim of this work package was to validate the SelfClean project concept and results. In order for this verification to take place contact plates, door knobs and cabinet handles were coated with the Sn-Ni/doped-TiO2 composite utilizing pulse plating technique that was developed in the previous WP5. The electrodeposition of tin-nickel alloy was accomplished using a commercial Elplatek chloride/fluoride bath operating at a temperature of 65–70 oC. The metal articles were tested in laboratory for the characterization of the mechanical and photocatalytic properties to determine the self cleaning – antibacterial activity of the coating along with the mechanical durability. Finally the metal articles were installed for three weeks in the Metropolitan hospital for testing in a real environment. The selection of the installation places took into account the usage of each place and the irradiation level of the indoor lightings. For evaluating the efficiency of the coatings three types of antibacterial measurements were selected: contact plate test, ATP test and swab tests. The demonstration activities can be characterized as successful. The overall estimation of the consortium of the SelfClean project is that the results up till now are very promising and towards the correct direction for achieving to produce coatings with excellent anti-microbial and self-cleaning activity. It should be mentioned that in some cases (e.g. plates plated with Sn-Ni/TiO2 by the up-scale bath), showed in the 82% of the measurement better results comparing to the common surfaces of the hospital. Thus, the consortium considers to have achieved proving the overall concept of the SelfClean project.

Work Package 7: Dissemination and exploitation of project results
Work Package 7 started in month 1 and was 100% completed at month 24. In order to disseminate the technology developed during the previous work packages as widely as possible, few results from the research have been already reported in several trade shows and conferences. Within WP-7 the following deliverables have been successfully completed on time: D7.1 Project website, D7.2 Patent and novelty search, D7.3 Interim plan for the use, dissemination and exploitation of the knowledge, D7.4 Filling of patents, D7.5 Video presentation of the project's achievements and 7.6 Final consortium exploitation plan.

For the deliverables due during the 24 months of the project Dr. Jan Boye Rasmussen from the SME ELPLATEK, as exploitation manager, was leading this work. However, all the partners are aware of the importance of the dissemination and exploitation and they are heavily involved to ensure good dissemination of the SelfClean project. The objectives of this work package are to publicise the project and to maximise exploitation opportunities for the SMEs during and after the project. Contributions from all partners involved in this WP were in accordance with the latest DoW without deviation with regards to the WP objectives and use of resources.

Work Package 8:
The Project Management is continuous throughout the project. Project co-ordinator planed, organised & monitored the project for administrative, legal and contractual matters, quality and standards representation and implementation. Budgets were monitored & cost statements were collated & reviewed prior to submission to the EC Project Manager and Work package Leaders reviewed work packages as necessary.
Potential Impact:
The successful conclusion of this project has a greatly positive impact on the business growth prospects of the SMEs partners plus its associated positive impacts on their European supplier network and employment level such as the the metalworking and metal articles sector (MMA or Metalworking) which is a very large sector that provides technologies, services and equipment to all other industrial sectors. A further added benefit resulted by optimizing the pulse current codeposition process and thus achieving reduction in energy and time. Moreover, a huge societal profit is gained due to the alleviation of the health system resulting from the reduction of disease transmission.

The idea of a self cleaning – antibacterial coating that will solve the problem of viruses and bacteria transmission through inanimate objects such as surfaces of common touched objects like knobs, handles etc, will be very easily accepted by the majority of the society. Dramatically reducing the main factor for hospital-acquired infections and spread of epidemics will not only offer a feeling of security to people, but will also give to the companies involved in the industries of electroplating, metalworking and surface engineering an impetus for increasing turnover.

There is a huge global market that will buy, use and get benefitted from self cleaning – antibacterial coatings that will manage to dramatically minimize the possibility of diseases’ transmission: Hospitals, hotels, schools, restaurants, means of public transportation, public buildings, workplaces etc.

It is a fact that in the next decade hospitals will be coping with a fast increase in the availability of innovation and advanced technologies, as well as with increasing patients' expectations and demands. Hospitals will be expected to be even more efficient, to continue reducing inappropriate admissions and length of stay and to further improve the coordination between inpatient care and out of hospital treatments. Reducing the spread of diseases transmitted in the hospitals is one of their top priorities.

It is estimated that around 15.000 hospitals operate in Europe that consist a large number of potential customers. Even though this number still increases only at a few European countries, the trend to reduce transmission of virus and bacteria in hospitals and hence reduce healthcare expenditures is more than imperative.

Hospital-acquired infection (HAI) or nosocomial infection is a term coined to define an infection acquired in hospital by a patient, who was admitted for a reason other than that infection, and in whom the infection was not present or incubating at the time of admission. Around 1.4 million patients per day are affected by hospital-acquired infections (HAI) throughout the world. According to the European Commission in 2010, there are approximately 4.1 million healthcare associated infections and 50,000 attributable deaths in the European Union each year. In 2009, the mean HAI prevalence was around 7.1%, while the incidence was only 5.1%. This reveals that despite initiative taken to reduce the incidence of new infection, the inability to treat the existing ones completely has added to the burden of the health expenditure in Europe.

According to European Centre for Disease Prevention and Control (ECDC) in 2008, the burden on healthcare systems in Europe is immense, resulting in an additional 16.0 million days of hospital stay per year. Assuming the average daily cost of a hospital stay to be €334.0 the total annual healthcare cost for the EU-27 can be estimated at €7.00 billion. However, this value does not include the indirect costs linked to loss of income, or the intangible costs associated with physical and emotional suffering. The most frequent infections are urinary tract infections (UTIs), followed by respiratory tract infections, infections post- surgery, bloodstream infections (BSIs) and others. In developed countries, HAI concerns 5.0 % to 15.0 % of hospitalized patients and can affect 9.0 % to 37.0 % of those admitted to intensive care units (ICUs). In Europe 2008, an estimated five million HAI at least occur in acute care hospitals annually, contributing to 135,000 deaths and representing around 25.0 million extra days of hospital stay and a corresponding economic burden of €13.00 billion to €24.00 billion.

Viruses and bacteria are also easily transmitted at public means of transport due to the large number of people using them. One in ten people have admitted avoiding public transport because of worries over cleanliness and general hygiene levels. The coating of bars and poles used by passengers in buses, trains and subway trains with a self-cleaning and anti-bacterial product, could change the way people see public means of transport, leading in direct profit to the transportation industry.

Diseases are also transmitted via contaminated door knobs and taps at public buildings, hotels or workplaces. Even though hygiene rules are usually determined, they are often skipped or skimped. Schools, universities, authority buildings and offices of private companies consist an enormous range of potential customers.

The consortium has identified the following market sectors that the SelfClean products will target.

There are around 15.000 hospitals operating in Europe with approximately 3.000.000 beds. With an average of 6 beds per room that gives 500.000 rooms, which with the addition of 500.000 other rooms (administrative, storage rooms and toilets) reach the number of 1.000.000. Assuming an average number of 20 metal articles per room, the potential quantity of coated objects that can be sold is 20,000,000 items.

According to Otus Analytics there are more than 14.700 hotels in Europe operated by the major international chains, which are more eager to invest to our product’s functionality. With an average of 190 rooms per hotel and 20 items per room, the SelfClean potential sales could reach 55,860,000 objects.

Electroplating Companies
The consortium plans to start licensing the product’s electroplating process in 2019, given that the consortium SMEs cannot satisfy the market’s needs at this time. The procedure will target the 22,000 electroplating companies operating in the EU27.

Other Technological applications
TiO2 nanopowder can be also used in other technological applications such as photocatalytic paints, sprays for buildings, solar cells and cars. The manufacture of Titanium Dioxide (TiO2) nanoparticles is a significant niche industry and demand for these materials is strong. 50,400 tons of nanoparticle TiO2 was produced in 2010, representing 0.7% of the overall TiO2 market. By 2015, production is projected to increase to 201,500 tons.

School buildings
The school buildings sector consists a really big market with enormous sales potential. According to Eyridice database, there are 132,692 school buildings in France, UK, Greece, Denmark, and Spain132.692. With an average estimation of 100 items sold per school, there is a capacity of 13.269.200 items only for these 5 countries. Extending the market to the other counties of E27 and the rest of Europe will give obviously great results.

Selfclean promotional material include:

• SELFCLEAN website: A project website where the project is presented to the general public Useful information about the project is presented including the objectives, the benefits and the workplan of the project. Additionally the partners of the project are presented, their role in the project and a link to partner’s website is provided.
• SELFCLEAN Reports: public versions of the project reports and deliverable are available at the public website
• SELFCLEAN Leaflet: a leaflet providing basic information about the project main goals, the technical approach, the expected achievements and a list of project participants and its consortium. This serves as the project’s “business card” and is distributed, by the project beneficiaries, as widely as possible in any appropriate occasion. The leaflet is available on the public website
• SELFCLEAN Publications: throughout the project lifetime, the partners produce articles defining the project and its available results. At several occasions representatives of the Consortium and the Project Coordinator in particular assist and assure presentations to promote and explain the aims of the project and if available publish the public results at these occasions. Beside the promotion of the project by SMEs’ representatives during their national assemblies, specific sessions are planned at conferences, trade shows and exhibitions.

List of Websites:

Project Coordinator: National Technical University of Athens, NTUA

Contact persons:
Prof Litsa Pavlatou, NTUA (Scientific)

Dr Kostas Chrysagis, NTUA (Project Management)
Tel: +30210-7723110
Fax: +30210- 7723285