Nanomaterials for photocatalysis and applications in environmental remediation and renewable energy

• Viet Van Pham and
• Wee-Jun Ong

Beilstein J. Nanotechnol. 2023, 14, 722–724, doi:10.3762/bjnano.14.58

• ]. Semiconducting photocatalyst nanomaterials, such as SnO2, TiO2, MoS2, g-C3N4, and Bi-nanostructures have been proven efficient for a range of applications, including organic pollutant removal, NOx degradation, renewable energy production, and waste-to-energy conversion [15][17][18]. Figure 1 shows a general

• development of advanced materials based on semiconductors (i.e., carbon-modified hexagonal boron nitride (MBN), MgO@g-C3N4, and TiO2@MWCNTs) have indicated a highly efficient photocatalytic performance for phenol removal using a low-power visible LED light source. For NO degradation, a visible light source

Bismuth-based nanostructured photocatalysts for the remediation of antibiotics and organic dyes

• Akeem Adeyemi Oladipo and
• Faisal Suleiman Mustafa

Beilstein J. Nanotechnol. 2023, 14, 291–321, doi:10.3762/bjnano.14.26

• -scheme photocatalytic system. Li et al. [42] constructed spindle-shaped BiVO4-RGO-g-C3N4 Z-scheme photocatalysts for the highly effective degradation of antibiotics. The 1-D Z-scheme ternary nanocomposites had a very high photooxidation response. According to the authors, ciprofloxacin and tetracycline

• effectively prevent charge carriers from recombining, increasing the photoactivity of BiFeO3. For instance, Wang et al. [180] synthesised spindle-like g-C3N4/BiFeO3 nanosheets, and the nanocomposite successfully degraded methyl orange by 75% under visible light, which is better than g-C3N4 or BiFeO3 alone

Photoelectrochemical water oxidation over TiO₂ nanotubes modified with MoS₂ and g-C₃N₄

• Phuong Hoang Nguyen,
• Thi Minh Cao,
• Tho Truong Nguyen,
• Hien Duy Tong and
• Viet Van Pham

Beilstein J. Nanotechnol. 2022, 13, 1541–1550, doi:10.3762/bjnano.13.127

• efficiency. Through a comparison of MoS2/TNAs and g-C3N4/TNAs, it was found that TNAs modified with MoS2 and g-C3N4 exhibited a current density of, respectively, 210.6 and 139.6 μA·cm−2 at an overpotential of 1.23 V vs RHE, which is 18.2 and 12 times higher than that of pure TNAs under the same conditions

• . The stability of the MoS2/TNAs heterojunction is higher than that of g-C3N4/TNAs. Keywords: band structure; g-C3N4/TiO2; MoS2/TiO2; photoelectrochemical; water splitting; Introduction Hydrogen energy has become a target pursued in the energy development strategies of many countries and regions

• the required amounts of noble metals and materials such as CdS or ZnS [26][27][28][29]. There are many low-bandgap semiconductors that were coupled with TNAs, including MoS2, WS2, MoSe2, g-C3N4, Cu2O, and CuO. MoS2 is a semiconductor with a narrow bandgap (1.9 eV at room temperature) exhibiting unique

Recent trends in Bi-based nanomaterials: challenges, fabrication, enhancement techniques, and environmental applications

• Vishal Dutta,
• Ankush Chauhan,
• Ritesh Verma,
• C. Gopalkrishnan and
• Van-Huy Nguyen

Beilstein J. Nanotechnol. 2022, 13, 1316–1336, doi:10.3762/bjnano.13.109

• , efficiently contributing to enhanced photocatalytic performance. Another research group reported that photoreduction and hydrothermal techniques were used to successfully synthesize a new 2D/2D Bi2MoO6/g-C3N4 S-scheme composite including Au as a co-catalyzer [107]. Bi2MoO6/g-C3N4/Au had a photocatalytic

• activity in RhB degradation that was 9.7 times and 13.1 times higher than that of Bi2MoO6 and g-C3N4, respectively. In the Bi2MoO6/g-C3N4/Au system, the higher photocatalytic activity can be attributed to the abundance of active sites and the enhanced separation efficiency of photogenerated carriers. The

Rapid fabrication of MgO@g-C₃N₄ heterojunctions for photocatalytic nitric oxide removal

• Minh-Thuan Pham,
• Duyen P. H. Tran,
• Xuan-Thanh Bui and
• Sheng-Jie You

Beilstein J. Nanotechnol. 2022, 13, 1141–1154, doi:10.3762/bjnano.13.96

• environment, human health, and other biotas. Among the technologies to treat NO pollution, photocatalytic oxidation under visible light is considered an effective means. This study describes photocatalytic oxidation to degrade NO under visible light with the support of a photocatalyst. MgO@g-C3N4

• heterojunction photocatalysts were synthesized by one-step pyrolysis of MgO and urea at 550 °C for two hours. The photocatalytic NO removal efficiency of the MgO@g-C3N4 heterojunctions was significantly improved and reached a maximum value of 75.4% under visible light irradiation. Differential reflectance

• spectroscopy (DRS) was used to determine the optical properties and bandgap energies of the material. The bandgap of the material decreases with increasing amounts of MgO. The photoluminescence spectra indicate that the recombination of electron–hole pairs is hindered by doping MgO onto g-C3N4. Also, NO

Spindle-like MIL101(Fe) decorated with Bi₂O₃ nanoparticles for enhanced degradation of chlortetracycline under visible-light irradiation

• Chen-chen Hao,
• Fang-yan Chen,
• Kun Bian,
• Yu-bin Tang and
• Wei-long Shi

Beilstein J. Nanotechnol. 2022, 13, 1038–1050, doi:10.3762/bjnano.13.91

• photogenerated charges and resultant photocatalytic activity [26]. Up to date, a few semiconductors such as ZnO [39], TiO2 [19] and g-C3N4 [40] have been employed to construct heterojunctions with MIL101(Fe). The abovementioned MIL101-based heterojunctions are all traditional heterojunctions which promote the

• construct Bi2O3-based heterojunctions has attracted extensive interest. A large number of Bi2O3-based heterojunctions, such as Bi2O3/g-C3N4 [46], WO3/g-C3N4/Bi2O3 [47], Bi2O3/BiOCl [48], Bi2O3/ZnO [49], and Bi2O3/BiVO4 [50] have been synthesized. However, to the best of our knowledge, there is no report

Solar-light-driven LaFe_xNi_1−xO₃ perovskite oxides for photocatalytic Fenton-like reaction to degrade organic pollutants

• Chao-Wei Huang,
• Shu-Yu Hsu,
• Jun-Han Lin,
• Yun Jhou,
• Wei-Yu Chen,
• Kun-Yi Andrew Lin,
• Yu-Tang Lin and
• Van-Huy Nguyen

Beilstein J. Nanotechnol. 2022, 13, 882–895, doi:10.3762/bjnano.13.79

• nanoparticles via the sol–gel method to decompose rhodamine-B under visible light irradiation. With the assistance of H2O2, it shows a synergistic effect between photocatalytic reaction and heterogeneous photo-Fenton-like reaction [23]. Furthermore, the strategies of being loaded over supports (such as g-C3N4

Hierarchical Bi₂WO₆/TiO₂-nanotube composites derived from natural cellulose for visible-light photocatalytic treatment of pollutants

• Zehao Lin,
• Zhan Yang and
• Jianguo Huang

Beilstein J. Nanotechnol. 2022, 13, 745–762, doi:10.3762/bjnano.13.66

• shown in Supporting Information File 1, Table S3, in comparison with cellulose-derived Ag2O-nanoparticle/TiO2-nanotube (Ag2O-NP/TiO2-NT) composites [31], g-C3N4/TiO2- nanotube (g-C3N4/TiO2-NT) composites [32], and H3PW12O40/TiO2 nanocomposites [33] reported by our group, the hierarchical Bi2WO6/TiO2-NT

• composite delivered similar three-dimensional interwoven structures that comprised the composite nanotubes. The Ag2O-NP/TiO2-NT and H3PW12O40/TiO2 composites exhibited excellent photocatalytic performances under UV light irradiation, while the g-C3N4/TiO2-NT and Bi2WO6/TiO2-NT composites had a wider light

• response to the visible spectral region. Besides, under visible light irradiation, Bi2WO6/TiO2-NT composites show better photocatalytic degradation activities than that of g-C3N4/TiO2-NT composites. Based on these cellulose-derived nanocomposites, structure–activity relationships between photocatalytic

A comprehensive review on electrospun nanohybrid membranes for wastewater treatment

• Senuri Kumarage,
• Imalka Munaweera and
• Nilwala Kottegoda

Beilstein J. Nanotechnol. 2022, 13, 137–159, doi:10.3762/bjnano.13.10

Tin dioxide nanomaterial-based photocatalysts for nitrogen oxide oxidation: a review

• Viet Van Pham,
• Hong-Huy Tran,
• Thao Kim Truong and
• Thi Minh Cao

Beilstein J. Nanotechnol. 2022, 13, 96–113, doi:10.3762/bjnano.13.7

• organic semiconductors such as graphitic carbon nitride (g-C3N4) [71]. When acting as an auxiliary photocatalyst, SnO2 promotes the photocatalytic activity of the primary material [38][70][75][76]. Wu et al. reported the visible-light-driven elimination of NO over hydrothermally synthesized BiOBr/SnO2 p–n

• TiO2 and BiOBr, recent works reported the successful combination of SnO2 nanomaterials with conjugated polymers such as graphitic carbon nitride (g-C3N4) and polyaniline (PANI), yielding metal-free visible-light-driven photocatalysts for addressing NO gas pollution. Such combinations hold great

• . Regarding g-C3N4, Zou et al. successfully deposited SnO2 quantum dots (QDs) on g-C3N4 sheets by a simple physical mixing process. The authors indicated that the SnO2/g-C3N4 photocatalyst had a twice as high NO removal efficacy than bare SnO2 QDs and a low NO2 generation upon exposure to visible light for 30

Nanoporous and nonporous conjugated donor–acceptor polymer semiconductors for photocatalytic hydrogen production

• Zhao-Qi Sheng,
• Yu-Qin Xing,
• Yan Chen,
• Guang Zhang,
• Shi-Yong Liu and
• Long Chen

Beilstein J. Nanotechnol. 2021, 12, 607–623, doi:10.3762/bjnano.12.50

• photocatalyst (i.e., poly(p-phenylene)) for PHP was reported, but did not attract much attention due to the low hydrogen evolution rate (HER) [11]. In 2009, Wang et al. reported a novel metal-free polymeric photocatalyst (i.e., graphitic carbon nitride (g-C3N4)), which could efficiently reduce protons to

• generate hydrogen under visible-light irradiation, for the first time. After that, g-C3N4 triggered substantial research interest [12][13][14]. Various strategies have been developed to improve the PHP activity of g-C3N4, such as introducing heterojunctions [15][16][17], copolymerization [18][19][20

• than those of the triazine-amine-based P7 (Figure 2) and bulk g-C3N4. Hence, incorporation of more than one kind of electron acceptors in the polymer structure could enhance the photocatalytic efficiency. In addition, Tan et al. [49] developed several D–A CPs with carbazole (D), benzothiadiazole (A1

Boosting of photocatalytic hydrogen evolution via chlorine doping of polymeric carbon nitride

• Malgorzata Aleksandrzak,
• Michalina Kijaczko,
• Wojciech Kukulka,
• Daria Baranowska,
• Martyna Baca,
• Beata Zielinska and
• Ewa Mijowska

Beilstein J. Nanotechnol. 2021, 12, 473–484, doi:10.3762/bjnano.12.38

• . studied the photoactivity of PCN doped with S in the CO2 reduction reaction. The yield of CH3OH over the unit area of the photocatalyst was almost 2.5 times higher than of pristine PCN [35]. Recently, co-doping of g-C3N4 with two non-metallic elements has been also studied. This strategy can enhance

Microwave-induced electric discharges on metal particles for the synthesis of inorganic nanomaterials under solvent-free conditions

• Vijay Tripathi,
• Harit Kumar,
• Anubhav Agarwal and
• Leela S. Panchakarla

Beilstein J. Nanotechnol. 2020, 11, 1019–1025, doi:10.3762/bjnano.11.86

• copper. Graphitic carbon nitride (g-C3N4) or graphite powder (commercially available) are used as carbon source. g-C3N4 is synthesized and characterized according to [18]. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) confirms the formation of g-C3N4 (Figure S1 in Supporting

• Information File 1). The reactions were carried out in quartz or Teflon beakers. A Teflon beaker also served as a carbon and fluorine source for the experiments. Typically, 100 mg of acid-treated metal powder mixed either with graphite powder or g-C3N4 (50 mg) were placed inside a domestic kitchen microwave

• growth promoter. Typically, a mixture of activated metal (100 mg), sulfur powder (25 mg) and g-C3N4 (50 mg) were added to a Teflon beaker and irradiated with microwaves. It is important to note that in the absence of carbon (graphite/g-C3N4), the arc synthesis yielded a mixture of metal and metal oxide

Improved adsorption and degradation performance by S-doping of (001)-TiO₂

• Xiao-Yu Sun,
• Xian Zhang,
• Xiao Sun,
• Ni-Xian Qian,
• Min Wang and
• Yong-Qing Ma

Beilstein J. Nanotechnol. 2019, 10, 2116–2127, doi:10.3762/bjnano.10.206

• performance. Li et al. synthesized composites of mesoporous (001)-TiO2 and C applying a one-pot hydrothermal strategy in the presence of glucose and hydrofluoric acid (HF). The composites an exhibited excellent visible-light-driven photocatalytic performance [14]. Chen et al. synthesized a composite of g-C3N4

Synthesis of novel C-doped g-C₃N₄ nanosheets coupled with CdIn₂S₄ for enhanced photocatalytic hydrogen evolution

• Jingshuai Chen,
• Chang-Jie Mao,
• Helin Niu and
• Ji-Ming Song

Beilstein J. Nanotechnol. 2019, 10, 912–921, doi:10.3762/bjnano.10.92

• effective strategy, the combination of C-doping with nanocomposite semiconductors, is presented in this work. C-doped g-C3N4 (CCN) was prepared by supramolecular self-assembly and subsequently a number of CdIn2S4/CCN composite photocatalysts were designed and fabricated though in situ decoration of CdIn2S4

• to analyze the crystal structure, morphology, elementary composition, optical properties and catalytic mechanism. The CdIn2S4/CCN nanocomposites with optimal CdIn2S4 content exhibited a maximum H2 production rate of 2985 μmol h−1 g−1, almost 15 times more than that obtained using pure g-C3N4 (205

• . Keywords: C-doped g-C3N4; CdIn2S4; composite materials; hydrogen generation; photocatalysis; Introduction The serious environmental concerns and increasing global energy demand have instigated growing awareness in the field of alternative energy generation over the past few decades. Photocatalysis

Reduced graphene oxide supported C₃N₄ nanoflakes and quantum dots as metal-free catalysts for visible light assisted CO₂ reduction

• Md Rakibuddin and
• Haekyoung Kim

Beilstein J. Nanotechnol. 2019, 10, 448–458, doi:10.3762/bjnano.10.44

• heating at 130–190 °C for 5−20 h. It is observed that hydrothermal exposure of acid-treated graphitic carbon nitride (g-C3N4) nanosheets at low temperature generated larger NFs, whereas QDs are formed at higher temperatures. The formation of GCN hybrid materials was confirmed by powder X-ray diffraction

• conduction band (CB) and valence band (VB) edge positions, exhibit efficient charge separation, have a large surface area, and it must be cost effective. Considering the above factors, nontoxic metal-free catalysts, such as graphitic carbon nitride (g-C3N4) and reduced graphene oxide (rGO) have received wide

• attention in recent years for CO2 reduction and water splitting applications [12][13][14][15][16][17]. Both g-C3N4 and rGO have a two-dimensional sheet structure with high surface area and possess appropriate band edges for CO2 reduction. Also, g-C3N4 and rGO are inexpensive and easy to synthesize. Despite

Oriented zinc oxide nanorods: A novel saturable absorber for lasers in the near-infrared

• Pavel Loiko,
• Tanujjal Bora,
• Josep Maria Serres,
• Haohai Yu,
• Magdalena Aguiló,
• Francesc Díaz,
• Uwe Griebner,
• Valentin Petrov,
• Xavier Mateos and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2018, 9, 2730–2740, doi:10.3762/bjnano.9.255

• , e.g., MoS2, WS2 [16][17], black phosphorus (BP) [18]), and topological insulators (TIs, e.g., Bi2Te3, Sb2Te3 [19][20], graphitic carbon nitride (g-C3N4) [21]). In the PQS regime, such structures enable the generation of nanosecond pulses at high repetition rates (up to MHz) and they are attractive for

Improving the catalytic activity for hydrogen evolution of monolayered SnSe_2(1−x)S_2x by mechanical strain

• Sha Dong and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2018, 9, 1820–1827, doi:10.3762/bjnano.9.173

• strengthen the hydrogen binding on graphitic carbon nitride (g-C3N4), whereas compressive strain had the opposite effect. Yan et al. [49] showed that large elastic strains influence the catalytic activity of WC for HER. Very recently, 2D SnSe2(1−x)S2x alloys have been synthesized experimentally [35]. To our

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

• support. The photogenerated electrons are transported from the Mn-doped TiO2 through RGO and were found to reduce the adsorbed Cr(VI) [137]. A Ti–SBA-15–g-C3N4 material was also shown to exhibit higher Cr(VI) photoreduction under visible light illumination. The Ti moiety in Ti–SBA-15 can extract the

• conduction band electrons of g-C3N4 after visible light irradiation followed by transfer of electrons to Cr(VI) to produce Cr(III) [138]. Photocatalytic reduction of Cr(VI) using CNT-modified TiO2 Carbon nanotubes (CNTs) have also been shown to possess excellent electronic and conductive properties. Waldmann

Perovskite-structured CaTiO₃ coupled with g-C₃N₄ as a heterojunction photocatalyst for organic pollutant degradation

• Ashish Kumar,
• Christian Schuerings,
• Suneel Kumar,
• Ajay Kumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2018, 9, 671–685, doi:10.3762/bjnano.9.62

• Ashish Kumar Christian Schuerings Suneel Kumar Ajay Kumar Venkata Krishnan School of Basic Sciences and Advanced Materials Research Center, Indian Institute of Technology Mandi, Kamand, Mandi 175005, Himachal Pradesh, India 10.3762/bjnano.9.62 Abstract A novel graphitic carbon nitride (g-C3N4

• )–CaTiO3 (CTCN) organic–inorganic heterojunction photocatalyst was synthesized by a facile mixing method, resulting in the deposition of CaTiO3 (CT) nanoflakes onto the surface of g-C3N4 nanosheets. The photocatalytic activity of the as-synthesized heterojunction (along with the controls) was evaluated by

• studying the degradation of an aqueous solution of rhodamine B (RhB) under UV, visible and natural sunlight irradiation. The CTCN heterojunction with 1:1 ratio of g-C3N4/CT showed the highest photocatalytic activity under sunlight irradiation and was also demonstrated to be effective for the degradation of

Mechanistic insights into plasmonic photocatalysts in utilizing visible light

• Kah Hon Leong,
• Azrina Abd Aziz,
• Lan Ching Sim,
• Pichiah Saravanan,
• Min Jang and
• Detlef Bahnemann

Beilstein J. Nanotechnol. 2018, 9, 628–648, doi:10.3762/bjnano.9.59

• . Such materials have already been applied in various environmental and energy conversion applications [36]. Recently, the evolution of a metal-free semiconductor, graphitic carbon nitride (g-C3N4), has been discovered as an alternative for plasmonic photocatalysts. This metal-free semiconductor by

• photocatalytically inert due to their unfavourable band edge position compared to the redox potential of targeted species. An effective approach to overcome this restriction was to integrate the nonstoichiometric materials (tungsten oxide (W18O49)) with graphitic carbon nitride (g-C3N4). The g-C3N4 was used to

Sugarcane juice derived carbon dot–graphitic carbon nitride composites for bisphenol A degradation under sunlight irradiation

• Lan Ching Sim,
• Jing Lin Wong,
• Chen Hong Hak,
• Jun Yan Tai,
• Kah Hon Leong and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2018, 9, 353–363, doi:10.3762/bjnano.9.35

• Laboratory, Department of Environmental Science and Engineering, Indian Institute of Technology (ISM), Dhanbad 826004, Jharkhand, India 10.3762/bjnano.9.35 Abstract Carbon dots (CDs) and graphitic carbon nitride (g-C3N4) composites (CD/g-C3N4) were successfully synthesized by a hydrothermal method using

• revealed new signals for carbonyl and carboxyl groups originating from the CDs in CD/g-C3N4 composites while X-ray diffraction (XRD) results showed distortion of the host matrix after incorporating CDs into g-C3N4. Both analyses signified the interaction between g-C3N4 and CDs. The photoluminescence (PL

• ) analysis indicated that the presence of too many CDs will create trap states at the CD/g-C3N4 interface, decelerating the electron (e−) transport. However, the CD/g-C3N4(0.5) composite with the highest coverage of CDs still achieved the best bisphenol A (BPA) degradation rate at 3.87 times higher than that

Review on optofluidic microreactors for artificial photosynthesis

• Xiaowen Huang,
• Jianchun Wang,
• Tenghao Li,
• Jianmei Wang,
• Min Xu,
• Weixing Yu,
• Abdel El Abed and
• Xuming Zhang

Beilstein J. Nanotechnol. 2018, 9, 30–41, doi:10.3762/bjnano.9.5

• nano-system in which water and CO2 were catalyzed to form H2 and CO in this integrated system [66]. Jiang et al. showed a thylakoid-inspired multishell g-C3N4 nanocapsule with orderly stacked nanostructures, which exhibited enhanced visible-light harvesting and electron-transfer properties for high

• combination of g-C3N4 and electron mediator through π–π stacking, in addition to a significantly enhanced coenzyme regeneration rate [89]. Coenzyme regeneration is also of great importance in CO2 reduction with the help of enzymes. Formaldehyde dehydrogenase is a typical one that selectively achieves methanol

• ) Schematic illustration of the PS I reaction center. (B) One-step fabrication process of the immobilized artificial PS I (IAPSI) in the form of the g-C3N4-M film. (C) Simple procedures to fabricate the IAPSI microreactor. (D) Photograph of the as-fabricated IAPSI microreactor, in which the inset presents the

Hydrothermal synthesis of ZnO quantum dot/KNb₃O₈ nanosheet photocatalysts for reducing carbon dioxide to methanol

• Xiao Shao,
• Weiyue Xin and
• Xiaohong Yin

Beilstein J. Nanotechnol. 2017, 8, 2264–2270, doi:10.3762/bjnano.8.226

• concentration of Nb2O5 was favorable to form NaNbO3 nanorods and nanoplates, while a lower concentration of NaOH facilitated formation of NaNbO3 cubes [12]. Shi and his co-workers synthesized polymeric g-C3N4 coupled with NaNbO3 nanowires for enhancing photocatalytic reduction of CO2 into renewable fuel [13

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

• of the most abundant elements on the earth. In the past two decades, carbon-based materials such as graphene, graphitic carbon nitride (g-C3N4), fullerenes and carbon nanotubes (CNTs) have been explored for various applications such as Li-ion batteries [22], supercapacitors [23], energy storage [24

• scientific community such as heteroatom doping [34], noble metal doping [35], coupling with semiconductors [36] and nanocomposite formation with carbon-based materials, such as graphene [37] and g-C3N4 [38], to enhance the photocatalytic efficiency. Among the various types of nanocomposites, the materials

• focussed our review on only two of the 2D morphology of carbon materials, graphene and g-C3N4, and their nanocomposites for photocatalytic energy generation and environmental remediation applications. In this review, we firstly discuss the synthetic procedures and salient properties of these two 2D carbon