Haining Tian

Uppsala University | UU · Department of Chemistry - Ångström Laboratory

Photobiocatalytic CO2 reduction represents an attractive approach for conversion of solar light and abundant resources to value-added chemicals. However, the design of suitable systems requires a detailed understanding of the interaction between the artificial photosensitizer and biocatalyst interface. In this work, we investigate the effect of sur...

As a new class of organic photocatalysts, polymer dots show a potential application in photocatalytic hydrogen peroxide production coupled with chemical oxidation such as methanol oxidation. However, the poor methanol oxidation ability by polymer dots still inhibits the overall photocatalytic reaction occurring in the neutral condition. In this wor...

The constrained effectiveness of photodynamic therapy (PDT) has impeded its widespread use in clinical practice. Urgent efforts are needed to address the shortcomings faced in photodynamic therapy, such as photosensitizer toxicity, short half‐life, and limited action range of reactive oxygen species (ROS). In this study, a biodegradable copolymer n...

Photobiocatalytic CO2 reduction represents an attractive approach for conversion of solar light and abundant resources to value-added chemicals. However, the design of suitable systems requires a detailed understanding of the interaction between artificial photosensitizer and biocatalyst interface. In this work, we investigate the effect of surfact...

Dye-sensitized photoelectrodes consisting of photosensitizers and molecular catalysts with tunable structures and adjustable energy levels are attractive for low-cost and eco-friendly solar-assisted synthesis of energy rich products. Despite these advantages, dye-sensitized NiO photocathodes suffer from severe electron-hole recombination and facile...

Development of efficient, stable, and recyclable photocatalysts for organic synthesis is vital for transformation of traditional thermal organic chemistry into green sustainable organic chemistry. In this work, the study reports an electrostatic approach to assemble meso‐tetra (4‐sulfonate phenyl) porphyrin (TPPS)tetra (4‐sulfonate phenyl) porphyri...

Systems integrating quantum dots with molecular catalysts are attracting ever more attention, primarily owing to their tunability and notable photocatalytic activity in the context of the hydrogen evolution reaction (HER) and CO2 reduction reaction (CO2RR). CuInS2 (CIS) quantum dots (QDs) are effective photoreductants, having relatively high-energy...

Efficient photosensitizers are crucial for advancing solar energy conversion and storage technologies. In this study, we designed and synthesized a novel organic dye, denoted as YB6, for p‐type dye‐sensitized solar cells (p‐DSCs) and photoelectrochemical H2O2 production. YB6 features an extended conjugated π‐bridge derived from indacenodithieno[3,2...

Organic polymers based on the donor–acceptor structure are a promising class of efficient photocatalysts for solar fuel production. Among these polymers, poly(9,9-dioctylfluorene-alt-1,2,3-benzothiadiazole) (PFBT) consisting of fluorene donor and benzothiadiazole acceptor units has shown good photocatalytic activity when it is prepared into polymer...

The development of p-n tandem dye-sensitized solar cells (t-DSCs) offer the potential for substantial open-circuit voltages, holding great promise for a wide range of applications, particularly in the fields of...

Exciton migration in organic polymer dots (Pdots) is crucial for optimizing photocatalytic reactions at the particle surface, such as hydrogen evolution and carbon dioxide reduction. Despite the use of Pdots...

Organic polymeric photocatalysts have been attracted scientists’ interests during past years due to their low-cost, tunable bandgaps and energy levels, and promising photocatalytic performance. Making the traditional hydrophobic polymeric photocatalyst into nano-particles with size less than 100 nm, so-called polymer dots (Pdots), has shown signifi...

In recent years, heterocyclic organic compounds have been explored as molecular electrocatalysts in relevant reactions for energy conversion and storage. Merging mimetics of biological systems that perform hydride transfer with rational synthetic chemical design has opened many opportunities for organic molecules to be tuned at the atomic level con...

CO2 reduction through semiartificial photosynthesis represents an attractive approach for conversion of solar light and abundant resources to value-added chemicals. Herein, designing highly efficient biocompatible photocatalysts that can boost CO2 reduction by the enzyme is desirable. In this work, biohybrid assemblies composed of a phenoxazine-bas...

The development of p-n tandem dye-sensitized solar cells (t-DSCs) offer the potential for substantial open-circuit voltages, holding great promise for a wide range of applications, particularly in the fields of photovoltaics and photoelectrochemical devices. Most reported t-DSCs are liquid-based, which suffer from unsatisfied stability due to the l...

In recent years, heterocyclic organic compounds have been explored as molecular electrocatalysts in relevant reactions for energy conversion and storage. Merging mimetics of biological systems that perform hydride transfer with rational synthetic chemical design has opened many opportunities for organic molecules to be tuned at the atomic level con...

Developing low‐cost and efficient photocatalysts to convert CO2 into valuable fuels is desirable to realize a carbon‐neutral society. In this work, we report that polymer dots (Pdots) of poly[(9,9′‐dioctylfluorenyl‐2,7‐diyl)‐co‐(1,4‐benzo‐thiadiazole)] (PFBT), without adding any extra co‐catalyst, can photocatalyze reduction of CO2 into CO in aqueo...

Developing low‐cost and efficient photocatalysts to convert CO2 into valuable fuels is desirable to realize a carbon‐neutral society. In this work, we report that polymer dots (Pdots) of poly[(9,9′‐dioctylfluorenyl‐2,7‐diyl)‐co‐(1,4‐benzo‐thiadiazole)] (PFBT) without adding any extra co‐catalyst can photocatalytic reduction of CO2 into CO in aqueou...

Biohybrid photosynthesis systems, which combine biological and non-biological materials, have attracted recent interest in solar-to-chemical energy conversion. However, the solar efficiencies of such systems remain low, despite advances in both artificial photosynthesis and synthetic biology. Here we discuss the potential of conjugated organic mate...

Developing light-harvesting systems with efficient photoinduced charge separation and long-lived charge-separated (CS) state is desirable but still challenging. In this study, we designed a zinc porphyrin photosensitizer covalently linked with viologen (ZnP-V) that can be prepared into nanoparticles in aqueous solution. In DMF solution, the monomer...

Organic polymers based on the donor-acceptor structure are a promising class of efficient photocatalysts for solar fuel production. Among these polymers, poly(9,9- dioctylfluorene-alt-1,2,3-benzothiadiazole (PFBT) consisting of fluorene donor and benzothiadiazole acceptor units has shown good photocatalytic activity when it is prepared into polymer...

Utilization of solar energy in organic semiconductors relies on complicated photophysical processes due to the strong electron−hole interactions. To gain a better understanding of these processes and their effect on the photocatalytic performance of non-fullerene acceptors (NFAs) within nano-particles (NPs), we compared the excited-state dynamics a...

Control of charge separation and recombination is critical for dye-sensitized solar cells and photoelectrochemical cells, and for p-type cells, the latter process limits their photovoltaic performance. We speculated that the lateral electron hopping between dyes on a p-type semiconductor surface can effectively separate electrons and holes in space...

Lateral intermolecular charge transfer between photosensitizers on metal oxide substrates is important for the understanding on the overall working principles of dye-sensitized systems. Such studies usually concentrate on either hole or electron transfer separately and are conducted in solvents with a high dielectric constant (εs) that are known, h...

A phenoxazine-based small organic donor POZ-M is designed and synthesized to prepare organic heterojunction nanoparticles (NPs) with a small acceptor ITIC for photocatalytic hydrogen production, giving a reaction rate up...

The development of photocatalysts to drive organic reactions is a frontier research topic. Organic polymers can be well tuned in terms of structural and photophysical properties and, therefore, constitute a promising class of photocatalysts in photoredox catalysis for organic synthesis. In this review article, we provide an overview of the concept...

Organic semiconductor-microbial photosynthetic biohybrid systems show great potential in light-driven biosynthesis. In such a system, an organic semiconductor is used to harvest solar energy and generate electrons, which can be further transported to microorganisms with a wide range of metabolic pathways for final biosynthesis. However, the lack of...

To gain a deeper understanding of the underlying charge processes in dye sensitized photocathodes, lateral electron hopping across dye-sensitized NiO photocathodes was investigated. For dye-sensitized systems, hole hopping across photoanodes has been studied extensively in the literature but no expansive studies on electron hopping in sensitized ph...

Solar conversion of water into the storable energy carrier H2 can be achieved through photoelectrochemical water splitting using light adsorbing anodes and cathodes bearing O2 and H2 evolving catalysts, respectively. Herein a novel photocathode nanohybrid system is reported. This photocathode consists of a dye-sensitized p-type nickel oxide (NiO) w...

Three conjugated polymers (CPs) consisting of truxene donor units and different acceptor units were synthesized and prepared into polymer dots (Pdots) for photocatalytic H2O2 production, exhibiting performance of over 100 mmol h‐1 gPdots ‐1. The best external quantum efficiency was determined to be 8.4 % at 450 nm in 60 min which is higher than the...

Electrochemical impedance spectroscopy (EIS) is a commonly used steady-state technique to examine the internal resistance of electron-transfer processes in solar cell devices, and the results are directly related to the photovoltaic performance. In this study, EIS was performed to study the effects of accelerated ageing, aiming for insights into th...

Production of renewable fuels from solar energy and abundant resourses, such as water and carbon dioxide, via photocatalytic reactions is seen as a promising strategy to adequately address the climate challenge. Photocatalytic systems based on organic polymer nanoparticles (PNPs) are seen as one avenue to transform solar energy into hydrogen and ot...

A semiartificial photosynthesis approach that utilizes enzymes for solar fuel production relies on efficient photosensitizers that should match the enzyme activity and enable long-term stability. Polymer dots (Pdots) are biocompatible photosensitizers that are stable at pH 7 and have a readily modifiable surface morphology. Therefore, Pdots can be...

A photocatalyst comprising binary organic polymer dots (Pdots) was prepared. The Pdots were constructed from poly(9,9‐dioctylfluorene‐alt‐benzothiadiazole), as an electron donor, and 1‐[3‐(methoxycarbonyl)propyl]‐1‐phenyl‐[6.6]C61, as an electron acceptor. The photocatalyst produces H2O2 in alkaline conditions (1 M KOH) with a production rate of up...

In this paper, the role of NiO surface states is assessed in a tandem dye-sensitized solar cell (t-DSSC) consisting of a 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid (P1) dye-sensitized NiO photocathode, a VG1-C8 dye-sensitized TiO2 photoanode and the I⁻/I3⁻ redox couple. The NiO surface states are proved to particip...

A photocatalyst comprised of binary organic polymer dots (Pdots) was prepared. The Pdots were constructed from poly(9,9‐dioctylfluorene‐ alt ‐benzothiadiazole), as an electron donor, and 1‐[3‐(methoxycarbonyl)propyl]‐1‐phenyl‐[6.6]C 61 , as an electron acceptor. The photocatalyst produces H 2 O 2 in alkaline conditions (1 M KOH) with a production r...

A biomimetic model complex of the [FeFe]-hydrogenase active site (FeFeOH) with an ethylene bridge and a pendant hydroxyl group has been synthesized, characterized and evaluated as catalyst for the light-driven hydrogen production. The interaction of the hydroxyl group present in the complex with 3-isocyanopropyltriethoxysilane provided a carbamate...

Aqueous dispersed conjugated polymer dots (Pdots) have shown promising application in photocatalytic hydrogen evolution. To efficiently extract photogenerated charges from type-II heterojunction Pdots for hydrogen evolution, the mechanistic study of photophysical processes is essential for Pdot optimization. Within this work, we use a PFODTBT donor...

A small organic molecule 2,1,3-benzothiadiazole-4, 7-dicarbonitrile (BTDN) is assessed for electrocatalytic hydrogen evolution on glassy carbon electrode and shows a hydrogen production Faradaic efficiency of 82% in the presence of salicylic acid. The key catalytic intermediates of reduced species BTDN–• and protonated intermediates are characteriz...

A global hydrogen economy could ensure environmentally sustainable, safe and cost-efficient renewable energy for the 21st century. Solar hydrogen production through artificial photosynthesis is a key strategy, and the activity of natural hydrogenase metalloenzymes an inspiration for the design of synthetic catalyst systems. [FeFe]-hydrogenase enzym...

(*) see ref.: "ACS Nano 2021, 15 (8), 13504−13515" DOI: 10.1021/acsnano.1c04126 or Hal-cea-03321066v1

A small organic molecule 2,1,3-benzothiadiazole-4, 7-dicarbonitrile (BTDN) is assessed for electrocatalytic hydrogen, showing a hydrogen production faradaic efficiency of 82% in presence of salicylic acid. The key catalytic intermediates of reduced species BTDN−• and protonated intermediates are identified and characterized by using various spectro...

A small organic molecule 2,1,3-benzothiadiazole-4, 7-dicarbonitrile (BTDN) is assessed for electrocatalytic hydrogen, showing a hydrogen production faradaic efficiency of 82% in presence of salicylic acid. The key catalytic intermediates of reduced species BTDN−• and protonated intermediates are identified and characterized by using various spectro...

Water electrolysis powered by renewable energies is a promising technology to produce sustainable fossil free fuels. The development and evaluation of effective catalysts are here imperative; however, due to the inclusion of elements with different redox properties and reactivity, these materials undergo dynamical changes and phase transformations...

The photophysical properties of Cu-deficient Cu0.2In1Sx quantum dots synthesized through a facile aqueous-based procedure have been investigated. Transient absorption experiments were carried out probing in the UV–vis, near-IR, and mid-IR regions, with the aim to (i) study the photophysical properties of the quantum dots and (ii) monitor kinetics o...

Organic semiconducting polymers dots (Pdots) have recently shown efficient photocatalytic activity for hydrogen evolution in an aqueous phase. However, colloidal Pdots face problems of aggregation and precipitation during the photocatalytic reaction due to unavoidable collisions between particles, thus resulting in a short catalytic lifetime. In th...

A small organic molecule 2,1,3-benzothiadiazole-4, 7-dicarbonitrile (BTDN) has been tested as electrocatalyst for hydrogen production. The catalyst shows a hydrogen production faradaic efficiency of 82% in presence of salicylic acid. Some of reaction mediators are identified and characterized by using various spectroscopic methods and density funct...

Panchromatic ternary polymer dots (Pdots) consisting of two conjugated polymers (PFBT and PFODTBT) based on fluorene and benzothiadiazole groups, and one small molecular acceptor (ITIC) have been prepared and assessed for photocatalytic hydrogen production with the assistance of a Pt cocatalyst. Femtosecond transient absorption spectroscopic studie...

This roadmap on Nanotechnology for Catalysis and Solar Energy Conversion focuses on the application of nanotechnology in addressing the current challenges of energy conversion: 'high efficiency, stability, safety, and the potential for low-cost/scalable manufacturing' to quote from the contributed article by Nathan Lewis. This roadmap focuses on so...

Surface states of mesoporous NiO semiconductor films have particular properties differing from the bulk and are able to dramatically influence the interfacial electron transfer and adsorption of chemical species. To achieve a better performance of NiO-based p-type dye-sensitized solar cells (p-DSCs), the function of the surface states has to be und...

Highly fluorescent carbon dots based on aspartic acid are synthesized and employed as a photosensitizer to drive photocatalytic hydrogen evolution with an [FeFe] hydrogenase in self-assembly systems, which has been systematically investigated to understand the electron transfer dynamics and its impact on photocatalysis efficiency.

In pursuit of inexpensive and earth abundant photocatalysts for solar hydrogen production from water, conjugated polymers have shown potential to be a viable alternative to widely used inorganic counterparts. The photocatalytic performance of polymeric photocatalysts, however, is very poor in comparison to that of inorganic photocatalysts. Most of...

Artificial photosynthesis, i.e., the conversion of light to chemical energy, is seen as a path to a more sustainable energy future. In this work, highly fluorescent aspartic acid-based carbon dots are synthesized and employed as photosensitizer to drive photocatalytic hydrogen evolution with an [FeFe] hydrogenase (CrHydA1). The direct interaction i...

Mesoporous NiO photocathodes containing the push-pull dye PB6 and alkyl-derivatized cobaloxime catalysts were prepared using surface amide couplings and analyzed for photocatalytic proton reduction catalysis. The length of the alkyl linker used to derivatize the cobalt catalysts was found to correlate to the photocurrent, with the highest photocurr...

In order to meet the ever-growing global energy demand with affordable and clean energy, it is essential to provide this energy by renewable resources and consider the eco-efficiency of the production and abundance of the utilised materials. While this is seldomly discussed for technologies still in the research state, addressing the issue of sustaina...

While half‐reactions using organic photocatalysts for hydrogen production are encouraging, systems with high efficiency without using sacrificing electron donors (SED) and showing full overall water‐splitting are still largely absent. Critical factors that are limiting the overall water‐splitting using organic photocatalysts are summarized, with a...

A facile surface-amide coupling method was examined to attach dye and catalyst molecules to silatrane-decorated NiO electrodes. Using this method, electrodes with a push-pull dye were assembled, and characterized by photoelectrochemistry and transient absorption spectroscopy. The dye-sensitized electrodes exhibited hole injection into NiO and good...

The study of p-type dye sensitized solar cells (p-DSCs) is appealing but challenging. Although the devices have been studied for 20 years, light conversion efficiency is lag far behind those of n-DSCs. Very recently, on the basis of a core-shell structure, a novel solid-state p-DSC (p-ssDSCs) has been fabricated, which showed great enhancement in o...

Energy is an important area of contemporary research, with clear societal benefits. It is a fast-developing and application-driven research area, with chemistry leading the discovery of new solids, which are then studied by physicists and materials scientists. Solar Energy Capture Materials introduces a range of the different inorganic materials us...

Heavy metal-free CuInS2 quantum dots (QDs) were employed as photosensitizer on a NiO photocathode to drive an immobilized molecular Re catallyst for photoelectrochemical CO2 reduction for the first time. A...

An indacenodithieno[3,2‐b]thiophene (IDTT) unit is used as a linker moiety to design a new p‐type dye—TIP—for solid‐state p‐type dye‐sensitized solar cells. Solar cells based on the TIP dye offered an efficiency of 0.18 % with an open‐circuit photovoltage of 550 mV and a short‐circuit photocurrent density of 0.86 mA cm⁻², which is better than those...

Fabrication of solid state p-type dye sensitized solar cells (p-ssDSCs) by using electron transport materials instead of the conventional I⁻/I3⁻ redox couple in liquid devices can completely eliminate the liquid phase and enhance the photovoltage. The performance of p-ssDSCs has been improved by optimizing dyes and electron transport materials. Mor...

Mimicking the nature is always beneficial for improving the performance of artificial system. The artificial photosynthesis as hydrogen production is one of the examples where we can find a big inspiration in nature. In this study, polymer nanoparticles (Pdots) prepared with a photoactive polymer PFODTBT and amphiphilic co-polymer under ultra-sonic...

Correction for ‘Ultrafast dye regeneration in a core–shell NiO–dye–TiO 2 mesoporous film’ by Lei Tian et al. , Phys. Chem. Chem. Phys. , 2018, 20 , 36–40.

A solution-processed NiO-dye-ZnO photocathode was developed for applications in both solid-state p-type dye-sensitized solar cells (p-ssDSCs) and p-type dye-sensitized photoelectrosynthesis cells (p-DSPECs). In p-ssDSCs, the solar cell using ZnO as electron transport material showed a short circuit current, up to 680 µA cm⁻², which is 60-fold large...

Dye-sensitized solar cells represent a type of device which converts solar energy into electricity based on molecular components. This is an attractive alternative for solar energy conversion because such devices can be made as low-cost, colorful, and transparent solar cell in contrast to the traditional semiconductor-based solar cells. In this cha...

Covalently linking photosensitizers and catalysts in an inorganic-organic hybrid photocatalytic system is beneficial for efficient electron transfer between these components. However, general and straightforward methods to covalently attach molecular catalysts on the surface of inorganic semiconductors are rare. In this work, a classic rhenium bipy...