Y1 Progress report | Piwai Tshuma

Solar-Driven Photocatalytic Degradation of Organic Pollutants:

Utilising Monolithic MOFs for Sustainable Water Remediation

During the first year of the fellowship, a series of advanced water-purifying materials called monolithic MOFs was successfully developed and characterised in the laboratory. These materials were tested for their ability to degrade harmful dyes in water under visible light. The best-performing material achieved 90.4% pollutant removal under optimised conditions. Repeated use of the materials confirmed that they remain effective and stable. Two research papers have been written and submitted to scientific journals; one is currently under revision at ACS Omega, and the other has been published in RSC Advances. Testing with the remaining materials is ongoing. Abstracts have been submitted to two international conferences for presentation at the end of 2026.

The project is supported by well-equipped laboratories at Midlands State University for MOF synthesis and basic characterisation. Advanced characterisation (SEM-EDX, TEM, UV-Vis DRS, FTIR) was conducted at the University of Pretoria, with additional equipment, including XPS, sourced externally by the mentor, Prof Mmantsae Diale. Technical support was provided by MSU lab technicians and 2 research assistants (Mercy Chaparadza and Lendly Moyo). The research benefits from a strong research community and collaborative network, including supervisor Prof Gift Mehlana (an expert in MOF synthesis, characterisation, and application), Prof Diale (who facilitates access to UP facilities and external equipment), and a collaboration with Chinhoyi University of Technology (CUT) for photocatalytic testing.

I am supervising two master's students and four undergraduate students, all of whom are working on projects aligned with this research, contributing to capacity building and knowledge transfer in MOF synthesis, characterisation, and photocatalysis.

Activities and progress

Quarter Q1 (July–September 2025) – Project Initiation

• Attended the FAR-LeaF orientation workshop (3–8 August 2025)

• 3-day project workshop with supervisor, research assistants, HoD, and lab technicians

• Procurement of consumables and equipment initiated

• Synthesis of monolithic MOFs commenced

Q2 (October–December 2025) – Synthesis and Characterisation

• All consumables delivered; synthesis completed

• Characterisation at UP (PXRD, TGA, FTIR, UV-VIS DRS, TEM) with mentor support

• BET pending due to instrument downtime (October–December)

• Preliminary photocatalytic testing conducted

• Challenge: Delays in sample analysis at UP resulted in the Chinhoyi University of Technology visit rescheduled to Dec 2025/Jan 2026

Q3 (January–March 2026) – Photocatalytic Testing and Manuscripts

• Full photocatalytic testing at Chinhoyi University of Technology

• Optimisation, Reusability, and Mechanistic studies done

• SEM-EDX and TEM analyses at UP

• Two manuscripts drafted, reviewed, and submitted

Q4 (April–June 2026) – Revisions and Ongoing Work

• Manuscript 1: Plasmonic Ag@ZIF-8 Monolith for Enhanced Visible Light Photocatalytic Degradation of Methylene Blue – ACS Omega (Manuscript ID: ao-2026-05428r.R1): under revision (minor revisions received).

• Manuscript 2: Visible-light driven photocatalytic degradation of tartrazine using Co@ZIF-8 monoliths – RSC Advances: Published

• Ongoing photocatalytic testing with remaining materials: intend to submit the 3rd manuscript in July 2026.

• Data compilation for scalability assessment (Year 2 planning).

• Planning for real wastewater testing (Year 2)

Year 1 of the FAR-LeaF II project has been highly productive, achieving all major experimental objectives and generating significant new knowledge in MOF-based photocatalysis. The project has demonstrated its soundness and doability through successful synthesis, characterisation, and photocatalytic testing, with two manuscripts submitted to reputable journals. Strong technical resources, mentorship, and collaboration have enabled this progress. The foundation laid in the first year positions the project well for the second year activities, including scalability assessment, real wastewater testing, and additional publications.

At the start of the programme, I viewed transdisciplinary research primarily as collaboration between different scientific disciplines. Over the past 12 months, my understanding has broadened significantly. I now recognise that transdisciplinary research goes beyond combining expertise in chemistry, engineering, and environmental science. It also involves engaging with non-academic stakeholders, considering local contexts, and addressing social, economic, and policy dimensions.

Working on water remediation in Zimbabwe has made me appreciate that technical solutions must be adapted to local realities—such as solar availability, infrastructure, and community needs. My collaboration with Chinhoyi University of Technology and discussions about real-world wastewater testing have reinforced the importance of translating research into practical, accessible solutions.

I have also learned that transdisciplinary research is a two-way learning process. My supervisor and mentor have shaped my scientific approach, while I have contributed insights from the local context. Additionally, I now see the policy implications of my work, as access to clean water is not just a technical issue but also a social and political one. My understanding has evolved from viewing transdisciplinary research as interdisciplinary collaboration to embracing it as a holistic, inclusive, and context-sensitive approach to addressing complex real-world challenges.

Annual report submitted by Dr Piwai Tshuma

(summarised for publication by Heidi Sonnekus for the FAR-LeaF Programme)